Volume 16, Issue 1

The magnetotelluric (MT) responses are explicitly solved for a stratiform earth containing multiple transitional layers in which the conductivity varies linearly with depth. In the model under consideration, any one homogeneous layer with constant conductivity or transitional one may be absent in the geometry. The traditional one-dimensional (1D) models with sharp boundaries will be obtained if all the transitional layers are absent in the geometry, while a special 1D model consisting of a sequence of contiguous transitional layers may be obtained if all the homogeneous layers (except the basement layer) are removed from the geometry. The tangential electric and magnetic fields as well as the surface impedance are analytically expressed by Airy functions. The analytical formula is validated in three theoretical examples by comparing with the results from available codes. The apparent resistivity and impedance phase on the surface of three different transitional models are illustrated to analysis the influence of the transitional layers on MT responses. The new formula provides an alternative way to obtain the analytic MT responses for the special layered earth.

Based on MODIS data from 2010 to 2020 and precipitation, air temperature, and soil moisture data of 33 meteorological stations in Jinsha River Basin from 1990 to 2020, the applicability of different remote sensing drought indexes in Jinsha River Basin was studied. These indexes include temperature condition index (TCI) and temperature vegetation drought index (TVDI), the results of vegetation condition index (VCI), vegetation supply water index (VSWI), standardized precipitation evapotranspiration index (SPEI), and standardized precipitation index (SPI) showed that TCI and TVDI, VSWI and TCI, VSWI and TVDI, VSWI and TVDI, VSWI and TVDI, VSWI and TVDI, VSWI and TVDI, SPEI and SPI, respectively. The correlation between VSWI and VCI was significant. VCI had the lowest correlation with SPEI and SPI. The average correlation coefficient between TCI and VSWI was similar. The correlation between VSWI, SPEI, and SPI was low in January, March, and October and reached significant or above levels in other months. TVDI had the highest correlation with SPEI and SPI. TVDI was significantly correlated with soil moisture every month of the year, indicating that TVDI can be effectively used for remote sensing drought monitoring in Jinsha River Basin and has strong adaptability. According to the temporal and spatial analysis of drought monitoring in the Jinsha River Basin by TVDI, the drought areas in December and January are mainly located in the middle reaches of the Jinsha River Basin, while the light drought areas are mainly located in the upper and lower reaches of the Jinsha River Basin. From March to June, the risk of severe drought increased in the middle reaches of the Jinsha River, and the moderate drought area in the Jinsha River Basin also increased. The drought from July to November was weaker than in the previous months. The moderate drought area is mainly located in the middle and lower reaches of the Jinsha River, and the mild drought area is mainly distributed in the upper reaches of the Jinsha River Basin.

Soil is an important carbon reservoir, and high-standard farmland construction projects have significant potential to promote low-carbon development. In order to study the management and implementation of low-carbon production in high-standard farmland construction projects, the tripartite evolution game model of government, business, and consumer is constructed based on the tripartite bounded rationality. Then, the behavior strategy of tripartite stakeholders is analyzed with the method of system dynamics. Finally, the evolution process of tripartite interaction behavior is simulated using the MATLAB tool. The results show that: (1) The subsidy and punishment mechanism of the government must be aligned. In addition, the net income of government regulation is higher than the sum of the government’s environmental governance fees and fines of non-regulation; (2) The government, business, and consumers all choose their own behavioral strategies based on their own interests. (3) When the government’s environmental governance fee reaches a particular value, the system will appear imbalanced. In light of this, it is suggested that the government should increase support for business and use media publicity, consumer subsidies, and other measures to promote the consumption of low-carbon products. The business should constantly reduce the cost of carbon emission reduction through technological innovation.

Low-frequency passive seismic (LFPS), discussed in recent years, has emphasized a strong correlation between the spectral properties and the presence of hydrocarbon reservoirs. While the theoretical background supporting this phenomenon is still debated, its application has been popular in Indonesia and exposes broad possibilities for exploration. In this study, we conducted a survey at an oil field in Central Java, Indonesia, investigating the case of using this technique as a direct hydrocarbon indicator (DHI). In spatial and temporal measurements, we examined the hydrocarbon-related energy above the reservoir boundary based on several attributes of passive seismic recordings: polarization, power spectral density (PSD), and vertical-to-horizontal spectral ratio (VHSR). We address some issues: (1) the anomalies are not always vertically polarized, so the use of VHSR is unlikely to be reliable; and (2) the anomalies are getting amplified during days, so in anomalies mapping, normalizing the amplification requires calibration. Regardless, LFPS is still applicable in quantifying hydrocarbon-related energy. We recommend using PSD as a primary spectral attribute for DHI. In addition, it is also critical to synchronize the measurements at different sites to obtain an unbiased quantification of hydrocarbon-related energy.

The Danube has a length of 588 km in the Republic of Serbia. The water transport on this river is underused. The hazardous events have a great impact on the traffic on this river, and the understanding of these events is of great importance. This study focuses on hazardous events on the Danube with the main focus on the port of Novi. The hazardous events used in this study are extreme air temperatures, devastating winds, drought, and heavy precipitation. The hazardous events were represented using geographic information systems (GIS), geostatistics, and numerical methods. The potential of the river transport network and the port capacity were analyzed and compared with the hazardous events of the last 30 years. The results showed that three areas of the port are of great importance for port security, and two areas are extremely affected by hazardous events. The distance of the port of Novi Sad from heavy precipitation events is 6.8 km in the southwestern direction. The periods of extremely low precipitation (climatic drought) were in 1994, 2008, 2012, 2015, 2019, and 2021. Extreme average maximum temperatures were in 1995, 2008, 2010, 2013, 2015, and 2019. On the other hand, minimum average temperatures were in 1994, 1996, 1998, 1999, 2017, and 2018, and the strongest winds were in 1995, 1998, 2003, 2009, 2012, and 2014. The methods and techniques of GIS, used in this research, have confirmed new potential geographical positions of the port that can be better adapted to future climate changes. Another main objective of this research is to recommend better spatial planning and construction of new green corridors.

A large set of Paleozoic volcaniclastic rocks is exposed in the northwestern margin of the Junggar Basin from the southern part of the Central Asian Orogenic Belt. The Carboniferous volcaniclastic strata in this area have been studied in depth, and an accurate chronostratigraphic framework of these strata has been established. However, there is a lack of sufficient geochronological data for the deposition times of the other Paleozoic volcaniclastic strata. In this study, zircon U–Pb dating of the Ordovician, Silurian, and Devonian volcaniclastic strata in the area reveals that the youngest age of the tuffite sample collected from the originally defined Ordovician strata is 398 ± 11 Ma, which represents the age of volcanic activity during the period of tuffite deposition. Based on this finding, the originally defined Ordovician strata are redefined as the Lower Devonian. The youngest ages of the silty tuff samples collected from the originally defined Silurian strata peak are 445–418 Ma, so its age is Upper Silurian. The youngest ages of the tuffaceous sandstone samples collected from the originally defined Devonian strata peak are 346–342 Ma, so these Devonian are redefined as the Early Carboniferous strata. Two Archean ages (2,501 ± 12 and 3,193 ± 8 Ma) were obtained in Silurian strata, thus confirming the existence of metamorphic rock basement in the provenance areas from which the sediments were derived.

Normalized difference vegetation index (NDVI) is one of the parameters of vegetation that can be studied by remote sensing of land surface with Sentinel-2 (S-2) satellite image. The NDVI is a nondimensional index that depicts the difference in plant cover reflectivity between visible and near-infrared light and can be used to measure the density of green on a piece of land. On the other hand, the dual-pol radar vegetation index (DpRVI) is one of the indices studied using multispectral synthetic aperture radar (SAR) images. Researchers have identified that SAR images are highly sensitive to identify the buildup of biomass from leaf vegetative growth to the flowering stage. Vegetation biophysical characteristics such as the leaf area index (LAI), vegetation water content, and biomass are frequently used as essential system parameters in remote sensing data assimilation for agricultural production models. In the current study, we have used LAI as a system parameter. The findings of the study revealed that the optical data (NDVI) showed a high correlation (up to 0.712) with LAI and a low root-mean-square error (0.0296) compared to microwave data with 0.4523 root-mean-square error. The NDVI, LAI, and DpRVI mean values all decreased between 2019 and 2020. While the DpRVI continued to decline between 2020 and 2021, the NDVI and LAI saw an increase over the same period, which was likely caused by an increase in the study area’s average annual rainfall and the cautious stance of the Red Global (RSG) project on sustainability.

It is a great challenge for sedimentologists to perform the facies analysis of shales due to the lack of macro-structures and high heterogeneity in shale, and thus, conventional research methods are poorly applied in the field of shale sedimentology. To establish a typical depositional model for marine shales, a new method adopted from marine carbonate rocks was employed to perform the microfacies analysis of marine shales of the Wufeng and Longmaxi Formation in Sichuan Basin. This method emphasizes the fact that many skeletal constituents in marine shales have specific bathymetric distributions, allowing for a better understanding of the depositional process of shales. With this approach, a total of nine microfacies were identified and two depositional models for marine shales were proposed. The depositional models show that sea levels were high during the Middle to Late Wufeng period, which was followed by a rapid regression that led to a significant sea-level drop by over 50 m at the topmost of the Wufeng Formation, and consequently, widespread fine-grained sandy shales with large amounts of benthic bioclasts were deposited in the study region. The eustatic sea-level changes recovered by using the method of microfacies analysis are in line with the global trend, indicating that the method has promising applications in the field of marine shale sedimentology.

A 6.9 magnitude earthquake hit Menyuan County, Haibei Prefecture, Qinghai Province, at 01:45 PM Beijing time on January 8, 2022 (17:45 PM GMT time on January 7, 2022). To explore the magnitude of the earthquake deformation and the affected area, this work combined optical remote sensing interpretation, interferometric synthetic aperture radar (InSAR) coseismic deformation extraction, and field surveys for research and analysis. Relying on the high-resolution Earth observation system of the Qinghai Remote Sensing Center for Natural Resources, high-resolution GF1D, GF2, and TRIPLESAT optical remote sensing images were acquired immediately after the earthquake. The airborne triangulation encryption method was used to carry out orthographic correction, fusion, and mosaic processing of digital orthophoto map (DOM) and digital surface model (DSM) images, and first-hand optical remote sensing images of the disaster areas were obtained. Based on differential InSAR (D-InSAR), small baseline subset InSAR (SBAS-InSAR) and lifting rail fusion methods, the coseismic deformation field and deformation rate of the lifting rail direction were obtained by using Sentinel-1A data processing before and after the earthquake. Combined with optical interpretation, InSAR deformation, and field investigation, the results show that the deformation trend of the line of sight (LOS) images to the north and south of the ascending and descending orbits show an obvious opposite trend. The surface shape variables are −50 to 45 cm and −65 to 72 cm, respectively, and the deformation rate before the earthquake reached 25 cm/year. The deformation field characteristics show that the earthquake was mainly due to thrust, and the coseismic deformation field fractured along the WNW‒ESE direction with a length of approximately 33 km. The areas affected by 10 mm, 20 cm, and 50 cm deformation magnitudes in the whole earthquake area were 975.14, 321.10, and 38.55 km 2 , respectively. Within 20 km, there were two main affected townships, namely, Sujitan Township and Huangcheng Mongolian Township. Within 50 km, there were four main affected towns and townships, namely, Sujitan Township, Mongolian Township of the Imperial city, Qingshizui town, and Haomen town.

One of the major challenges facing geochemistry, petrology, and volcanology researchers is the difficulty in determining the origin and paleo-flow directions of igneous and volcanic rocks. It is not possible to clearly determine origins and paleo-flow directions in areas with numerous volcanic centers. Anisotropy of magnetic susceptibility (AMS) is a valuable method that provides insights into the origins and paleo-flow directions of lavas that are complex to study. The presence of volcanic materials with thicknesses up to 1 km, coming from different sources at varied time intervals in the north of Lake Van, makes this area an ideal setting for implementing AMS in establishing paleo-flow directions. This study presents the magnetic mineralogy and AMS analysis of volcanic rocks from the Miocene to the Quaternary in the Lake Van region. We conducted isothermal remanent magnetization (IRM) and high-temperature susceptibility (HTS) studies to determine the magnetic mineralogy. IRM studies revealed that (titano)magnetite is responsible for the magnetization in most samples, while both (titano)magnetite and hematite are responsible for the rest. Alteration degrees and Curie temperatures of the rock samples were also determined through HTS measurements. There is good agreement between the anticipated directions of lava flow and our findings for nearly all volcanic rocks.

Based on the theoretical model of a soil plug column, the stress analysis of the soil plug column during the spinning process of steel casing is carried out, and the critical depth of the soil column is determined using the stress and torsional shear ratio of the soil column. The effect of factors such as casing wall thickness, surface load, and steel casing spinning speed on the critical depth of soil columns has been explored, and more reasonable construction process parameters have been obtained quantitatively. Combined with the construction of small net distance test piles at a distance of 2.5 m from the tunnel, the impact of the construction process on the existing shield tunnel has been explored. The results indicate that during the construction process, when the wall thickness of the steel casing does not exceed 0.012 m, the surface load does not exceed 15 kPa, the spinning speed of the steel casing is maintained at 5/4/2/4 m/h or 5/3/2/3 m/h (corresponding to soil depths of 2.5/9.5/6/14 m), and the soil height of the soil column is controlled within 11 m, it is not easy to generate soil plug inside the steel casing, and the soil column has strong torsional shear resistance. According to the measured data of adjacent tunnels, it has been found that the construction method of fully rotating steel casing bored pile can effectively reduce the impact on adjacent shield tunnels, and has a good microdisturbance effect, which can control tunnel deformation not exceeding 1 mm and maintain within the warning value range.

This study investigated the effects of food culture on the economic and ecological development of rural rivers and adolescents’ intentions toward tourism in high-risk leisure environments. The study applied a mixed-methods design. A questionnaire was designed and distributed to recruited participants, and 900 responses were collected and analyzed, with SPSS 26.0 used to perform basic statistical validation and Pearson’s correlation analysis. Structured interviews were conducted to collect the opinions of experts, tourists, and residents of the investigated areas. A multivariate analysis was used to analyze the results, which revealed that superior economic, societal, and ecological development is associated with greater leisure, tourism, and consumption intentions. However, varying levels of environmental literacy among tourists can present challenges. Problems such as tourism waste; overdevelopment; loss of historic architectural features; and pollution of water, forests, and air may deter young tourists from revisiting an area and diminish their willingness to engage in and share leisure experiences.

Frequent magmatic intrusion and eruption during the early Yanshanian in South China formed a unique and diverse igneous rock assemblage, mainly comprising granite, rhyolite, and some basic rocks. Nevertheless, the tectonic regime responsible for the formation of these granitic rocks remains controversial. The comprehensive available data suggest that the Jurassic granitic rocks formed during the period from 180 to 145 Ma, with an age peak at ca. 160 Ma. Jurassic rocks are predominantly concentrated in Wuyi, southern Hunan, northeast Guangdong, and southern Jiangxi, followed by the eastern Guangxi-western Guangdong areas, mainly including I-, S-, and A-type granites, and a few I–S transformation-type granites. These granitic rocks invariably exhibit enrichment in Rb, Th, U, and Pb, while Ba, Nb, Sr, P, and Ti are depleted, and variable Eu/Eu* ratios. The whole-rock Sr–Nd isotopic and zircon Hf isotopic compositions show that the Jurassic granitic rocks are mainly recirculation products of Paleo-Mesoproterozoic rocks, as well as the mantle-derived magma, which played a major role in the formation process. Among them, the granites in eastern Guangxi-western Guangdong and Northeast Guangdong areas display higher ε Nd ( t ) and ε Hf ( t ) values, suggesting a relatively larger contribution from mantle-derived materials. Based on the comprehensive regional geological data, we interpret that these Jurassic granitic rocks as a product of lithosphere extensional-thinning, tectonic-magmatic interaction formed during the process of flat-slab subduction.

Exploring the pattern of block vitality within cities and its influencing factors is an important topic in urban vitality research, which has great significance in promoting high-quality urban development. However, existing research has paid little attention to the spatial difference characteristics of daytime and night urban vitality and the differences in their influencing factors. Using the urban area of Kunming, China, as a case study, this study explores the differences in spatial patterns of daytime and night vitality at the intra-city block scale and analyses the differences in the main influencing factors of daytime and night block vitality using spatial regression models. The study obtains the following findings: (1) daytime block vitality in Kunming’s urban district (the urban Dist. of KM) is higher than night block vitality. The First Ring Area has the highest daytime block vitality, whereas the Second Ring Area has the highest night block vitality. (2) Block vitality in the urban Dist. of KM presents a polycentric structure. (3) There are obvious differences in the factors influencing urban vitality between daytime and night, with work accessibility, functional mixing, daily consumption accessibility, floor area ratio, and average building age, having different directions of influence on daytime and night urban vitality. (4) Daytime urban vitality in the urban Dist. of KM relies on work activities, while night urban vitality relies on residential activities. The results provide a scientific basis for urban land use layout, facility construction, and higher-quality urban planning and management, thus promoting sustainable urban development.

This article proposes random forest algorithm (RFA), multi-layer perception (MLP) artificial neural network (ANN), and support vector machine (SVM) method for classifying the fused data of Sentinel-2, Landsat-8, and Airbus Vision-1 satellites for the years 2016 and 2023. The first variant of fusion is performed for Sentinel-2 and Landsat-8 data to sharpen it to 10 m spatial resolution, while in the second case, Sentinel-2 and Airbus Vision-1 data are fused together to achieve a spatial resolution of 3.48 m. MLP-ANN, SVM, and RFA methods are applied to the sharpened dataset for the years 2023 and 2016 having spatial resolutions of 3.48 and 10 m, respectively, and a detailed comparative analysis is performed. Google earth engine is utilized for ground data validation of the classified samples. An enhanced convergence time of 100 iterations was achieved using MLP-ANN for the classification of the dataset at 3.48 m spatial resolution, while the same method took 300 iterations with the dataset at 10 m spatial resolution to achieve a minimum limit Kappa hat score of 0.85. With 10 m spatial resolution, the MLP-ANN achieved an overall accuracy of 96.6% and a Kappa hat score of 0.94, while at 3.48 m spatial resolution, the aforementioned scores are enhanced to 98.5% and 0.97, respectively. Similarly, with 10 m spatial resolution, the RFA achieved an overall accuracy of 92.6% and a Kappa hat score of 0.88, while at 3.48 m spatial resolution, the abovementioned scores are enhanced to 96.5 and 0.95% respectively. In view of the forgoing, the MLP-ANN showed better performance as compared to the RFA method. Graphical abstract

The karstification of carbonate rocks creates 3D maze voids that are normally controlled by fracture networks and sedimentary bedding. The spatial distribution and density of karst systems are usually complex and difficult to predict, demanding multidisciplinary studies at different scales of investigation to determine the spatial distribution and density of karst features and their possible links with cave systems controlled by the regional structural setting. The present study integrates geophysical datasets (gravity, electrical resistivity tomography - ERT, and ground penetrating radar - GPR) with a digital elevation model to investigate a karst system in the Irecê basin, a semiarid region of Brazil. Morphostructural lineaments reveal a NNW-SSE- and E-W-oriented structural setting of the crystalline basement, which is imprinted on the internal basin architecture, and surface drainage network. Negative gravity anomalies and high-gradient gravity zones indicate the main karstic zone, where karst landforms are concentrated. In addition, 2.5D gravity modeling provides the internal basin geometry, demonstrating that the karst system has evolved in the thickest sector of the basin. ERT profiles delineate the underground passages that connect dolines at depth. Finally, GPR data image shallow subsurface ghost-rock karstification that spread out from the surface to depth and that took advantage of vertical fractures and slightly arched bedding planes. Our results point out the role of the fracture corridors in channelizing hydrodynamic energy at a sufficiently high level to create caves by the total removal of dissolved material, whereas in the surrounding areas under low hydrodynamic conditions, overall shallow ghost-rock karstification took place, creating residual weathered rocks (alterites).

Based on land use classification data for the Yangtze River Delta region in 2000, 2015, and 2020, this study aims to explore the spatial and temporal evolution of ecosystem services value (ESV) in the region. By analyzing the land use structure and its dynamic changes, an ESV model is constructed. Furthermore, the study utilizes a geodetector to analyze the driving factors of ESV in the Yangtze River Delta region. The findings are as follows: (1) From 2000 to 2020, arable land was the predominant land use type in the Yangtze River Delta region. (2) The ESV in the region showed an upward trend followed by a decline from 2000 to 2020. Regulating services and supporting services have always been the core functions of ecosystem services in the region, with hydrological regulation contributing the most. (3) From a spatial perspective, there were significant differences in the spatial distribution of AESV (aggregated ecosystem services value) in the Yangtze River Delta region. The AESV changes in various cities within the region were evident, with a decreasing trend observed in most cities. (4) The sensitivity index of each land use type was less than 1, with forest land exhibiting the highest sensitivity and having the greatest impact on ESV. (5) Geodetector analysis revealed that the AESV in the Yangtze River Delta region is influenced by a combination of regional natural factors, economic factors, and social factors, and the interaction among different driving forces significantly enhances the spatial heterogeneity of AESV in the region.

The seismically active Ka-Ping Block within Xinjiang, China, represents a zone of potential earthquake hazards, and existing surface measurements cannot fully reflect the area’s sub-surface slip rates. To determine these slip rates and characterize the level of hazard that the study area may face in future years, using a cross-correlation of waveforms, we identified 432 repeat sequences along large faults (F1–F5) in the Ka-Ping Block between September 2009 and April 2022 and computed the annual slip rate for every sequence with the empirical relationship of the moment and the seismic magnitude. Spatial distribution images and temporal evolution characteristics of deep deformation in fault zones were constructed. We obtained five asperities in the Ka-Ping Block, the western portion of the PiQiang fault (F4) had a larger yearly slide rate than its eastern portion, and the southwest and eastern areas of the KEP station show an elevated risk of seismic activity within the next two years.

The rapid growth of outdoor digital twin data sets and advancements in 3D data acquisition technology have sparked interest in improving segmentation performance using deep learning. This research aims to analyze and evaluate different sampling strategies and optimization techniques while exploring the intensity information of outdoor point cloud data. Two sampling strategies, random and stratified sampling, are employed to divide a limited data set. Additionally, the data set is divided into point cloud data with and without intensity. The PointNet++ model is used to segment the point cloud data into two classes, vegetation and structure. The results indicate that stratified sampling outperforms random sampling, yielding a considerable improvement in mean intersection over union scores of up to 10%. Interestingly, the inclusion of intensity information in the data set does not universally enhance performance. Although the use of intensity improves the performance of random sampling, it does not benefit stratified sampling. This research provides insights into the effectiveness of different sampling strategies for outdoor point cloud data segmentation. The findings can contribute to the development of optimized approaches to improving segmentation accuracy in outdoor digital twin applications using deep learning techniques. Graphical abstract

This article discusses the types and characteristics of platform margin belts on both sides of the Kaijiang-Liangping trough in the Sichuan Basin during the Late-Permian Changhsingian age combined with the seismic reflection characteristics. The results show that there are four types of platform margin belts on both sides of the Kaijiang-Liangping trough: (1) steep-slope, single-platform margin belts controlled by faults; (2) steep-slope, single-platform margin belts controlled by paleogeomorphology; (3) steep-slope, multiple-platform margin belts controlled by paleogeomorphology; and (4) gentle-slope, multiple-platform margin belts controlled by paleogeomorphology. Reefs developed in the different types of platform margin belts exhibit different morphological characteristics and stacking patterns. Among all the reefs that developed in steep-slope, platform marginal belts are mainly characterized by aggradational accretion and different degrees of lateral migration in different directions. In contrast, the reefs developed in gentle-slope platform margin belts show distinctive characteristics of multiple bandings and lateral extension. Research suggests that the differences in the platform margin belts’ structure and reefs’ development rules are jointly controlled by a combination of syn-sedimentary fault activities, paleogeomorphology, and sea-level fluctuations. These results can be used to explore and predict reef reservoirs on carbonate platform margins.

This study aims to use attapulgite (ATT) and cement to modify loess as the lining material of landfills in loess areas and to exert the adsorption property of modified loess to ensure seepage prevention. It provides a safe, efficient, low-cost anti-seepage material for constructing a landfill in a loess area. For ATT-modified loess, when the content of ATT is less than 10%, the decrease rate of permeability coefficient is obvious, and when the content is more than 10%, the decrease rate becomes slow. After adding 5% cement on this basis, the permeability coefficient of ATT cement-modified loess is 8 × 10 −8  cm/s, which meets the standard requirements (≤10 −7  cm/s). The results show that the adsorption of Cu and Pb ions on ATT cement-modified loess is higher than that on pure loess. Cu and Pb ions’ adsorption rates are 99.2 and 98.5% in a single solution. In the mixed solution, the adsorption rates of copper and lead ions were 97.5 and 98.2%, respectively. Therefore, the study obtained the ratio of modified loess (85% loess + 10% ATT + 5% cement) that can not only meet the seepage prevention requirements of the landfill but also can adsorb heavy metal ions in the leachate, providing security for the landfill.

Since the early 1980s, several regions of Morocco have experienced alternating series of wet and dry periods related to climate change, with significant consequences for the country’s economy. This study aims to map flood hazards by using a hydraulic modeling approach, with a specific focus on the Oued (river) Zaouiat Sidi Hamza passing through Zaouiat Sidi Hamza township belonging to the High Ziz watershed (province of Midelt, region of Drâa-Tafilalet, Morocco). Hydraulic modeling and flood simulation were carried out followed by mapping of the flood hazard. The Oued Zaouiat Sidi Hamza River can cause torrential flooding issues, particularly during periods of heavy storms, impacting agricultural land and certain buildings on both river banks. All the cultivated areas developed alongside the river are at risk of flooding. Moreover, undermining and erosion of the river’s banks lead to rising high-water levels and flooding agricultural terraces. The use of geographic information systems and hydraulic modeling tools is essential to gain a deeper understanding of this situation. Also, the mapping of lineaments and fractures in the study area, carried out by satellite image processing, helped to quantify the directional influence of these lineaments on the flow of the hydrographic network, on the orientation of the circulation of surface water, and on the storage of groundwater. According to this study, the most vulnerable areas to flooding and erosion are those that receive the most water in the basin and have steep slopes. Decision-makers can use the results to produce development plans tailored to combat these risks and raise awareness among the population concerned, improving water resource evaluation and forecasting, as well as improving agricultural production.

The Ahe Formation in the Dibei Area is a key natural gas exploration formation in the northern structural belt. Based on geological data such as formation tests and physical properties, the tight reservoirs were determined using the empirical statistics method, distribution function method, oil-bearing occurrence method, and bound fluid saturation method reasonably. The lower limit of the oil-bearing physical properties of the layer was further analyzed for the differences between the methods. The pore-throat structure of tight sandstone was characterized by high-pressure mercury intrusion data, and the classification and evaluation standard of tight sandstone in the Ahe Formation in the Dibei Area was established combining fractal theory and physical property data. The results show that the lower physical limit porosity of the tight reservoir of the Ahe Formation in the Dibei Area is 2.4%, and the lower permeability limit is 0.021 × 10 −3  μm 2 . According to the fractal dimension characteristics of the mercury injection curve, the different structural characteristics of four types of pores (fracture, macropore, mesopore, and small pore) can be divided with the boundary values are 3,000, 1,000, and 100 nm; the tight reservoir of the Ahe Formation in Dibei Area can be classified into four categories: (a) type I reservoir ( Ф > 7%), mainly composed of fracture and macropore; (b) type II reservoir (4% < Ф < 7%), mainly made up of macropore and mesopore; (c) type III reservoir (2% < Ф < 4%), mainly formed by mesopore; and (d) type IV reservoir ( Ф < 2%) dominated by small pore, followed by mesopore.

It is necessary to evaluate the construction effect of viaducts and identify the viaducts that play a key role in road networks. Based on the node deletion method, this article proposes a method to identify the importance of viaducts in road networks. After applying this method to simulate the importance of viaducts in the highway networks in Yunnan and Guizhou Provinces from 2001 to 2020, the results show the following: (1) The viaducts with high importance were mainly built in 2002, 2009, 2015, and 2016. They are mainly distributed on expressways such as the HUKUN Expressway, HANGRUI Expressway, and YINBAI Expressway. Among the viaducts, the Mengzhai Bridge and Beipanjiang Bridge Hukun are the most important. (2) The importance of viaducts will increase, decrease, or increase first and then decrease. Among the years studied, 2012 and 2016 are important time nodes for change. The trend of changes is affected by the construction of highways and viaducts in other locations. In this road network, there are strong coupling relationships between nodes. (3) The importance of some viaducts is not prominent in the whole region, but that does not mean their construction value is low. They may have a high connectivity effect on specific regions from a local perspective.

Late Paleozoic plutons are widely distributed in the Alxa region, southernmost Central Asian Orogenic Belt, and provided an important clue in constraint for the closing time of the Paleo-Asian Ocean (PAO). In this article, we present new zircon U-Pb ages and whole-rock geochemical data from the Permian Huoersen and Zongnaishan plutons in the southern Alxa region. The Huoersen gabbro (ca. 285 Ma) is enriched in large-ion lithophile elements and depleted in high-field strength elements, similar to the features of continental marginal arc. They were most likely generated by partial melting of depleted mantle that was modified by subduction metasomatic fluids. The Zongnaishan granites (ca. 267 Ma) show characteristics of I-type granites and were generated in a syn-collision setting. The Huoersen granites (ca. 259 Ma) are peralkaline and have positive Ɛ Nd ( t ) (+1.2 to +1.5) values, exhibiting A 2 -subtype granites affinities. They were formed by melting of lower crust in post-collision extension setting. Based on geodynamic mechanism, a three-stage evolution model is delineated: subduction, syn-collision to post-collisional extension for oceanic branch of the PAO during the Permian. In general, the rock assemblages indicate a tectonic switch from subduction to post-collision extension regimes and the final closure of the PAO.

Hydrothermal activities occurred in the Yangtze block, South China, and affected the process of black shale sedimentation in the early Cambrian. Their specific influences, such as the sources, sedimentary environment, and mineralization, have not yet been revealed. Fortunately, the influences are explained through the geochemistry comparison of different wells FY1, XJ1, HY1, and XA1 in northwestern Hunan. The outcomes of the tectonic setting, distinguishable by element indicators, are disorganized. This is caused by the variable element composition, sedimentary recirculation of material source, and hydrothermal materials. FY1, the closest well to Zhangjiajie where Ni–Mo ores were formed by hydrothermal sedimentation, has more different features on the elemental geochemistry, but many indexes still indicate that it is normal sediments. XA1, which is far from the other wells and deposited in the deep-water basin, has significantly more differences in geochemical properties and shows more about normal marine deposition. XJ1 and HY1 are intermediate between them. Based on these wells, the hydrothermal contribution to the black shale sedimentation is not significant. However, some contents of trace and rare earth elements change widely because hydrothermal materials can diffuse and deposit over long distances. The concentration of Ag, As, Ba, Mo, Ba, U, and V generally has dozens of times higher than that of Upper Continental Crust. The early Cambrian environment was primarily anoxic/euxinic with enough sulfur, which is beneficial for enriching metal elements and organic matter. The sequence FY1, XJ1, HY1, and XA1 in turn has the same performance on the distance with Zhangjiajie, different intervals of suboxic environment and element enrichment, and hydrothermal-fluid-addition Ni abundance. Therefore, hydrothermal processes indeed provide materials for element enrichment and support the reducing environment, but the impact of hydrothermal activity decreases on the plane.

Simulation optimization of complex geological bodies is a necessary means to improve inversion accuracy and computational efficiency; thus, inversion of magnetotelluric (MT) based on unstructured grids has become a research hotspot in recent years. This article realizes the three-dimensional (3D) finite element forward modeling of MT based on the magnetic vector potential-electric scalar potential method, using unstructured grids as the forward modeling grid, which improves computational efficiency. The inversion uses the limited-memory Broyden–Fletcher–Goldfarb–Shanno (LBFGS) method, and in the process of calculating the objective function gradient, the quasi-forward method is used to avoid solving the Jacobian matrix, which has the advantages of requiring small storage space and fast computational efficiency. Finally, the 3D LBFGS inversion algorithm of MT based on unstructured grids was realized, and the inversion studies of classic and complex models verified the effectiveness and the reliability of the algorithm proposed in this article.

The red clay of the Chinese Loess Plateau (CLP) is an important geological archive for understanding the variability in the late Neogene East Asian monsoon. The periodicity of the summer monsoon of the red clay on the eastern CLP is dominated by eccentricity cycles within the constraints of the palaeomagnetic chronological framework, whereas global climate change characteristics represented by the deep-sea oxygen isotope record at that time show a dominating obliquity cycle. Here, we analyzed the East Asian summer monsoon proxies from the Shilou red clay section with the cyclostratigraphy method. The results show that the summer monsoon variation was dominated by obliquity, the optimum deposition rate was 4.451 cm/kyr, and the floating age of the Shilou red clay section was ca. 1.7 Ma. The late Neogene East Asian summer monsoon inferred from the eastern CLP was thus paced by the obliquity cycle, which is consistent with global change.

Real drilling near the upper Ordovician pinch-out line in the Tahe Oilfield shows that the drilling encountered karst reservoir. However, due to the transitional position between the denudation area and the overlying area and the special karst geological background, the existing drilling and completion data show that the reservoir space types in this area are complex and diverse. In this article, the classification of reservoir space near the Upper Ordovician pinch-out line and the extraction of logging response characteristics have been carried out based on drilling, logging, core, and crude oil quality data. Through this study, the classification scheme of karst reservoir space in the study area is proposed. The reservoir space types of karst reservoirs include fracture–cave, fracture–pore (light and low resistivity), fracture–pore (heavy and high resistivity), dissolved pore–pore (light and low resistivity), dissolved pore–pore (heavy and high resistivity), isolated pore (relatively isolated distribution of pores and fractures, weakly connected), and cave-type reservoir (sand and gravel filled or semi-unfilled). Furthermore, conventional logging parameters and five parameters sensitive to reservoir properties are extracted. The intersection maps based on the combination forms, fluid properties, and reservoir space effectiveness of different types of reservoir spaces are effective in distinguishing seven types of reservoir spaces and two types of stratified karst reservoirs. In this study, the reservoir space types and logging response characteristics of reservoirs near the Upper Ordovician pinch-out line are defined, which can provide a reliable geological basis for the quantitative identification and distribution evaluation of karst reservoirs.

River sand bodies have complex and changeable characteristics and distribution. In order to improve the accuracy and efficiency of target recognition, this study proposes a target recognition method of ultra-deep river sand bodies with improved deep learning under unmanned aerial vehicle (UAV) cluster. By constructing the cooperative target allocation model of UAV group, it is ensured that the targets of ultra-deep and large-area river sand bodies are collected. The gradient histogram is used to extract the image characteristics of ultra-deep river sand body and enhance the target image of ultra-deep river sand body. Bi-directional long short-term memory (Bi-LSTM) network model is constructed by introducing bidirectional recurrent neural network (RNN) to improve deep learning. Bi-LSTM neural network is used to construct the target recognition model of ultra-deep river sand body and complete the target recognition. The experimental results show that this method can extract the target edge completely and recognize the image edge accurately, and the average recognition accuracy under different ambiguities is higher than 95. It is proved that this method has high accuracy in sand body feature extraction and classification and has great application potential in river sand body target recognition.

There are many methods that discuss the prediction of flyrock distance in blasting operation, but none of them specifically discusses flyrock distance in sedimentary rock with low strength. The empirical method based on a statistical approach also has no specific research on it. This study aims to obtain a formula for predicting flyrock distance due to blasting on a sedimentary rock with low strength using ammonium nitrate fuel oil. A total of 196 samples were obtained from the blasting that has been operated. The variables included for building the new prediction model of flyrock distance are stemming, blast-hole height, powder factor, and average charge per blast hole. The analysis was carried out using a statistical approach with the concept of regression and correlation. Unlike the previous model that applied a dimensional approach, the new model set each of the predictor variables to have their respective regression coefficients in order to see how they play a role in predicting the flyrock distance. The results show that burden, stemming, blast-hole height, powder factor, and average charge per blast hole significantly affect the flyrock distance. The variance in flyrock distance can be explained uniquely 3.50% by burden, 10.74% by stemming, 2.55% by blast-hole height, 2.32% by powder factor, and 2.76% by average charge per blast hole. The new proposed model of flyrock distance is better than the previous model by looking at the mean absolute percentage error. To predict the flyrock distance of sedimentary rock with low strength, the new model can be used.

The ecological security of tourism provides an important guarantee of the sustainable development of regional tourism. In this study, the authors use the Driving Force-Pressure-State-Impact-Response model to construct a system to assess the ecological security of tourism in three provinces of Northeast China. We analyze the characteristics of the dynamic spatiotemporal evolution of the ecological security of tourism in 34 prefecture-level cities, one prefecture, and one region in three provinces of Northeast China from 2010 to 2019 and identify obstacles to this evolution. The results show the following: (1) The ecological security of tourism in Northeast China fluctuated and grew during the study period. Significant changes were observed in the rankings of the provinces in the ecological security of tourism. The pattern of spatial distribution has gradually shifted, from “high in the west and low in the middle” in 2010 to “slightly high in the middle-east and slightly low in the west” in 2019. (2) The ecological security of tourism exhibited prominent characteristics of spatial agglomeration on the whole, where the degree of agglomeration has gradually decreased over time. Economically developed cities in Central China exhibited strong local autocorrelation, and the majority had the characteristics of spatial agglomeration and dependence. (3) There were significant differences in obstacles to the ecological security of tourism among the cities (prefectures and regions) and provinces. Industrial sulfur dioxide emissions and urban population density are the main obstacles to the ecological security of tourism, while the pressure system has emerged as the main hindrance to improvements in it in the three provinces considered here. These results provide insights into the ecological security of tourism in the three provinces of Northeast China, as well as a theoretical reference for formulating and implementing the relevant measures of risk prevention and control. This study shows that increasing the protection of the tourism ecological environment and the construction of new energy sources, building complete tourism infrastructure, coordinating the relationship between tourists and the natural environment, adopting differentiated tourism development measures, and overcoming the obstacles will help to gradually improve the level of tourism ecological security in three provinces of Northeast China.

The Chang 8 reservoir of the Huanjiang Oilfield in the Ordos Basin is a tight sandstone reservoir with poor reservoir physical properties and uneven oil distribution. In this study, the effective reservoirs developed on a large scale under the condition of horizontal well volume fracturing technology of the Chang 8 Member was identified based on the data of core observation, experimental analysis, logging, oil test, and production dynamics, and the identification standard of effective reservoirs in terms of reservoir physical properties, oil content, and comprehensive logging characteristics of gas logging was established. This scheme allows for a thorough identification of the effective reservoirs for horizontal well development in tight sandstone reservoirs. The findings indicate that the study area’s tight oil resources can be successfully produced. The well logging results show that the oil-bearing property of sand bodies with oil stains is better than that of oil spots. The bottom limit of the acoustic wave time difference is 210 μs/m, the permeability is 0.03 mD, the porosity is 6.0%, the rock resistivity is 30 Ω m, and the total hydrocarbon gas measurement value exceeds five times the baseline. At the same time, the total oil thickness is greater than 6 m, and the thickness of a single sand body is above 4 m. We have defined the lower limit standard of high-efficiency reservoir of Chang 8 tight oil in L289 block of Huanjiang oilfield. According to the analysis of oil-bearing property, comprehensive logging display, and reservoir thickness, the geological “sweet spots” is optimized to provide reference for subsequent mining. Through comparative analysis, the rules and trends are found to provide a basis for selecting mining strategies. With the help of technical means such as numerical simulation and geological modeling, the prediction accuracy and decision-making effect are improved. By clarifying the lower limit standard of reservoir, optimizing geological “sweet spots” and avoiding risk areas, the mining efficiency is improved and the cost is reduced, which provides reference for similar oilfield development.

It is crucial for social sustainability that adolescents have access to social sports services fairly. However, there are few research studies on requirements for sports facilities and spatial accessibility of adolescents at a fine scale. Further, identifying the heterogeneity of the relationship between spatial accessibility and other factors and their scales simultaneously would be conducive to reveal the variations of spatial accessibility effectively under the potential scale effect. This research aims to explore the heterogeneity of spatial accessibility to sports facilities at a fine scale in Changsha, China. The Gaussian-based two-step floating catchment area model is first employed to evaluate spatial accessibility. Then, multiscale geographically weighted regression (MGWR) is applied to examine the relationship between spatial accessibility and its associated factors. The mean accessibility in Yuelu District (0.158) is the highest as well, and the standard deviation (0.236) is also the highest one. Both the accessibility (0.019) and its standard derivation (0.029) in Furong District are the lowest. The results show that there is a lack of balance of spatial accessibility for the clusters with different accessibility levels distributed in the study area. Some socio-economic factors, such as housing price and nighttime light intensity, have significant impacts on spatial accessibility for adolescents with spatial and scale heterogeneity by using MGWR. Based on heterogeneous distribution and association, suggestions for promoting spatial accessibility to sports facilities for adolescents are proposed.

To explore the mechanism of freeze–thaw cycles on the nutrient release of soft rock and sand-remodeled soils in Mu Us Sandy land of China, and to clarify the adaptation potential of remodeled soils with different proportions to extreme environment, indoor freezer simulation freeze–thaw experiments were carried out. The research results show that during the 2 cycles of freeze–thaw, the remodeled soil organic matter content and total nitrogen content (TNC) of the three treatments reached their peaks. Compared with that before freezing, T1, T2, and T3 treatments increased TNC by 40.9, 90.2, and 118.9%. The freeze–thaw cycle has a significant impact on the emergence rate of maize ( P < 0.05). In the soil during the 2 freeze–thaw cycles, the seedling emergence rate of maize is the highest. Compared with non-freeze–thaw treatment, the maize emergence rate of T1, T2, and T3 treatments was increased by 2, 3, and 3 times, and the emergence rate of T2 and T3 treatments was higher than that of T1 treatments under different freeze–thaw cycles. In conclusion, short-term freeze–thaw cycles can promote soil carbon and nitrogen mineralization and improve nutrient availability in Mu Us Sandy land, and T2 and T3 treatments have better adaptability to the environment.

In cases where blast vibrations cannot be measured with seismographs, empirical formulas are commonly used to predict vibration by specifying the peak particle velocity (PPV)-scale distance (SD) relationship. A new approach that provides important information about the relationship of seismic waves generated by blasting with rocks is the seismic quality factor ( Q ). The Q Factor depends on variables such as measurement distance, geological conditions, frequency, and seismic velocity. In this study, the seismic data obtained from blasting were used to determine the Q factor of the field, which in turn determines the Q value of the site. Blast vibrations were calculated using field equations derived from both the conventional and Q -factor methods. The vibration values measured by seismographs were then compared with the calculated data. The Q factor method, which takes into account the frequency content of the seismic waves, the velocity of the surface waves, and the absorption and damping properties of the seismic waves, predicted the vibration velocity with values very close to reality. However, the values obtained using the PPV-SD method are incompatible with the measurement results. The Q method is highly effective in cases where vibration measurement is not feasible. Additionally, the significance of directional changes in predicting blast vibrations is emphasized.

Oceanic igneous rocks throughout the Altai-Sayan Fold Belt (ASFB) in central-southern Siberia are often considered to be late Precambrian–early Paleozoic accreted elements of oceanic crust – often of uncertain paleogeographic or geodynamic origin. We explore the role of suprasubduction zone settings in the formation of different ASFB terranes. Our study offers a non-accretionary perspective on the tectonomagmatic development of basalt-bearing units in the ASFB on the example of the forearc terrane of the Ediacaran–early Cambrian Tannuola-Khamsara island arc (herein termed Sayan-Tuvan forearc zone). We describe the geochemistry, structural geology, and stratigraphic relations of basalts of the Aldynbulak, Uttug-Khaia, and Chingin formations, which are integral parts of the Sayan-Tuvan forearc zone. The Aldynbulak basalt samples mainly fall in the compositional fields of ocean island basalts and enriched mid-ocean ridge basalts (E-MORB) and likely derived from a deep mantle source. The Uttug-Khaia and Chingin basalts are N- and E + T-MORB-like basalts, carrying forearc geochemical signatures. Specifically, the Chingin Formation contains boninite dikes and is associated with a boninite-bearing ophiolite. Boninites are commonly associated with forearc magmatism and thus a forearc formation setting is likely. Tectonic and stratigraphic considerations imply that the Aldynbulak basalts formed first, followed by the Uttug-Khaia and later the Chingin basalts and boninites. A schematic model, involving decompression melting of the mantle, is proposed for the development of the studied forearc basalt suites that are linked with the growth of the Tannuola-Khamsara island arc system 580–540 million years ago.

Urban land use dynamics play a key role in the sustainable development of rapidly urbanizing regions, such as the Yangtze River Delta (YRD) in China. In this study, we employed geospatial and statistical methods comprising remotely sensed data, Geographic Information Systems, and the Spatial Durbin model to examine the complex changes in urban land uses. These techniques allowed for a broader assessment of the evolving urban landscape, emphasizing the significance of considering spatial relationships and socioeconomic panel data in the study area. The result indicated a substantial increase in built-up land within the YRD, rising from 6.83% in 2000 to 12.29% in 2020. This growth predominantly occurred at the expense of agricultural land, forests, and water bodies, with agricultural areas contributing over 90.2% to the built-up land expansion. The eastern cities experienced a more noticeable urban expansion compared to the western cities. The findings revealed a positive spatial spillover effect among neighboring cities, indicating a significant spatial clustering of built-up land. Population and urbanization emerged as primary drivers influencing both local and neighboring built-up land expansions. However, economic development, fixed asset investment, and transportation networks influenced the local areas of the YRD region but acted as inhibitors for the growth of neighboring areas. The result also suggests that industrial structures effectively curb local built-up land expansion without adversely affecting neighboring areas. These findings contribute to the existing knowledge by providing a wider understanding of land uses within the YRD region and valuable policy recommendations for sustainable urban planning in similar rapidly urbanizing areas.

Euler deconvolution is widely used for interpreting magnetic anomalies as it estimates the edges and depths of magnetic sources. Since this method was proposed, there has been an intensive effort to mitigate its primary deficiencies, namely, the generation of many spurious solutions and the high noise sensitivity. To select the most significant solutions, we adopt the strategy of constraining the moving window to the source edges, whose locations are estimated using the enhanced horizontal gradient amplitude method. On the other hand, we reduce noise propagation by performing a stable calculation of the vertical derivatives. For this purpose, we use the β-VDR method, a finite-difference method that yields a robust approximation of the vertical derivatives of magnetic data. The accuracy of the proposed technique is demonstrated on synthetic magnetic anomalies, providing the depths more precisely and being insensitive to noise. Application of this technique is also demonstrated on aeromagnetic anomalies from the Olympic Peninsula (USA), where the obtained result is in good agreement with known information of the study region.

To clarify the genetic mechanism for phase change of the hydrocarbon in the ultra-deep reservoirs, a case study from the Ordovician hydrocarbon in the Halahatang–Shunbei area (HSA), Tarim Basin, NW China, was conducted. The results show that the Ordovician reservoirs in the HSA are characterized as multi-phase reservoirs with a lateral co-existence of condensates, volatile-oil reservoirs, normal oil reservoirs, and heavy oil reservoirs. From north to south, there are regular variations in the geochemical characteristics of the Ordovician hydrocarbon in different blocks of the HSA, showing an increasing trend in GOR, dryness coefficients, methane contents, methane carbon isotope values, and ethane carbon isotope values, while a decreasing trend in oil densities and wax contents. Because the same Cambrian–Lower Ordovician source for the Ordovician hydrocarbon is observed and the kerogen-cracking gas is dominated in the HSA, the regular variations of the hydrocarbon phases and geochemical characteristics can be interpreted as records of biodegradation and multistage oil–gas filling rather than controlled by the source rock organofacies, oil cracking, and gas invasion. The formation mechanism of the Ordovician multi-phase reservoirs in the HSA suggests that the deep strata of the Tarim Basin hold potential for the exploration of natural gas resources.

Airports are among the constructions that must meet international standards and specifications established by the International Civil Aviation Organization (ICAO). Some of these parameters and criteria include topography, environmental, and operating circumstances. Navigation operations are also affected by terrain and human barriers, while noise, infrastructure, and weather factors affect the environment around airports. This article investigates using the interpretative structure model (ISM) and analytical network process (ANP) together as a new technique to select and determine the optimum site selection for constructing new international airports in the Nile Delta, Egypt. The criteria used (16 international criteria) are selected depending on the standards of the ICAO, field surveys, and previous studies. Nile Delta, Egypt, is chosen as a case study because it suffers from the lack of international airports and has a population of approximately 23 million. Therefore, new international airports must be established to serve this region, boost tourism, improve transportation, and stimulate commercial traffic. The results using the suggested new technique are compared with the traditional used methods for site selection, such as fuzzy-analytic hierarchy process. Landsat 8 images are used in this research. A quality test using the area under the curve and the receiver operating characteristic curve was applied to evaluate the new technique for site selection of international airports, depending on calculating the highest suitability index for each proposed site. From the quality tests, it is deduced that the suggested method (ISM–ANP) for airport site selection is more accurate than any other traditional method. ArcGIS 10.5 software is used to draw the final digital maps containing the proposed resulted sites. As a result, three new locations for the construction of international airports were found and selected throughout the research region (Delta Nile, Egypt) based on the used mathematical models. Therefore, the proposed novel method for determining the locations of international airports is thought to be effective and feasible, and it can be used to determine the locations of any development projects in general, particularly in developing countries, which benefits the decision-makers in making the right decisions.

Fe-deposits in Thailand are mostly located along the Loei Fold Belt in Central Thailand. The study areas, Khao Lek (KL) and Khao Thab Kwai (KTK), have Fe-deposits hosted in contact metamorphized Permian limestone and Permo-Triassic volcanic rocks. Magnetite forms over a wide range of geological conditions and incorporates various trace elements into its cubic spinel structure. The KL and KTK Fe-skarn deposits are mainly composed of massive magnetite. The main discriminator elements for magnetite are characterized by the distribution of Mg, Al, Si, Ca, Ti, V, Cr, Mn, Co, Ni, and Cu. Thus, this study focused on the chemical characteristics of magnetite to identify the origins of the iron ore deposits. This study investigated the trace element chemistry of the magnetite using laser ablation inductively coupled plasma mass spectrometry. The high Ca + Al + Mn and low Ti + V and Ni/Cr + Mn contents of hydrothermal magnetite in the KL and KTK deposits support a typical skarn origin, and the textural and trace element features of the KL and KTK magnetite are analogous to those of typical calcic-Fe skarn deposits worldwide. Graphical abstract

The development of the functional settlement typology methodology is of academic and practical importance as it incorporates the social, economic, and demographic dimensions of regional development. Rural settlements are seen as a base for labor; traditional urban centers have become a base for commuters, while at the same time, new economic centers are emerging where capital investment is accumulating. This article presents the research conducted in the Srem region (located in the province of Vojvodina) to determine the functional typology of the settlement, which is of social, economic, and demographic importance for the region itself and for Serbia as a whole. This well-known immigration area in Serbia has been inhabited for centuries for its specific economic and political reasons. The very intensive economic activities of the last two decades have been influenced by development investments and contributed to the functional transformation of the settlements. The census data from 2022 make it possible to determine a functional typology of settlements in the Srem region using the factor method (principal component analysis). The article aims to explain the basic characteristics of functional types of settlements and to determine the mechanisms of their territorial distribution, which would be helpful in the future planning and organization of local and regional development of the Republic of Serbia.

Recent metaheuristic approaches are extensively and intensively being implemented to the interpretation of gravity anomalies due to their superior advantages. We emphasize the application of Hunger Games Search (HGS), a newly established metaheuristic inspired by hunger-driven instincts and behavioral choices of animals, to elucidate gravity data for geothermal energy exploration and volcanic activity study. After recognizing the modal features of the objective function tailored and tuning the algorithm control parameters involved, HGS has been trial-tested on simulated data sets of different scenarios and finally experienced in two field cases from India and Japan. Notably, a second moving average strategy has been successfully integrated into the objective function to eradicate the regional component from observed responses. Post-inversion uncertainty appraisal tests have been further implemented to comprehend the reliability of solutions obtained. The solutions retrieved by HGS have been unbiasedly compared in terms of convergence rate, accuracy, stability, and robustness with the solutions of the commonly used particle swarm optimization algorithm. Based on the results accessed, the theoretical and field cases presented could be recuperated more precisely, stably, robustly, and coherently with the available geophysical, geological, and borehole verification, as HGS is able to better explore the model space without compromising its capability to efficiently approach the global minimum. This novel global optimization method can thus be considered as a promising tool in geothermal energy investigations and the study of volcanic activities.

With the continuous development of Earth Observation technology, resolution of imagery and gridded data has significantly increased, leading to a rapid increase in data volume. To efficiently acquire and analyze these vast amounts of imagery and gridded data, image tiling technology has been developed to effectively access data of interested areas. Tiling technology divides large-scale image data into smaller tiles, providing fast, accurate, and efficient access support for imagery and gridded data. The spatial grid model, as the foundational framework of the new generation of geographic spatial information, plays a critical role in the retrieval, integration, services, and applications of imagery and gridded data resources. When tiling image data based on the spatial grid model, it always generates both complete and incomplete tiles. Particularly, when conducting image tile retrieval using the same rule-based grid in the retrieval area, incomplete tile phenomena along the boundary regions of the retrieved images often occur, resulting in gaps within the retrieval area. To tackle this issue, in this study, we present a new topological model called the Grid Six-Intersection Model (G-6IM), specifically designed for regular rectangular grids, to accurately represent boundary issues in image tiling. Through a practical case study, we demonstrate the effectiveness and practical application potential of the proposed G-6IM model, providing new insights and guidance for the improvement and optimization of imagery and gridded data tiling technology.

The conflict between the supply and consumption of water resources (WR) is a growing concern, and water scarcity has become a major obstacle to the sustainable development of Chinese cities. To address this issue, the resilience assessment regulation model has proven to be an effective tool for decision makers. This model helps them determine how to improve the resilience of WR building systems and mitigate potential risks and threats. The aim of this article is to explore the evaluation and regulation of the resilience of WR building systems, with the goal of alleviating the WR crisis and promoting sustainable development. Through the construction of an evaluation index system, determination of index weights, design of evaluation models, and application of case studies, the fuzzy comprehensive evaluation method was employed to assess the resilience of WR systems. Additionally, an evaluation regulation model was established, along with the proposed regulation method. The evaluation index system consists of four dimensions: flexibility, adaptability, resilience, and fault tolerance.

The present study aims to identify whether the delineation of potential groundwater potential zones (GWPZs) is essential for monitoring surface and conserving underground water resources. This study analysed the morphology of earth surface characteristics such as geomorphology, lineament density, lithology, slope, soil types, land use and land cover, drainage density, land surface temperature, normalized difference vegetation index, rainfall, and topographic wetness index parameters to delineate the potential groundwater zones. This article applies the analytical hierarchy process (AHP) and multi-influence factor (MIF) methods to identify potential groundwater zones in the Tirunelveli and Tenkasi districts of Tamil Nadu, India. In the AHP method, individual parameter's geometric mean and normalized weights were determined using the pair-wise matrix analytical method. Remote sensing-geographic information system (RS-GIS) techniques were used to generate thematic map layers from normalized weights to delineate GWPZs. The GWPZs were classified as Very Low, Low, Medium, High, and Very High. The result shows that the GWPZs were identified as 3.57, 0.55, 6.62, 58.09, and 31.21% in the study area for the five classes, respectively. In this study, the thematic maps were also prepared by assigning fixed scores and weights from the MIF approach. In the MIF approach, GWPZs were classified into five classes and identified as 3.16, 0.33, 2.14, 61.21, and 33.16% in the study area, respectively. GWPZ maps were evaluated for both MIF and AHP techniques using the Kappa statistics method with agreement values of 0.77 and 0.72%, respectively. This study's GIS-RS method is more proficient and efficient in delineating the GWPZs.

Knowledge of the Coulomb dynamic coefficient of friction of snow is a vital input parameter for the estimation of run-out distance, velocity, forces, and lateral spread of the snow avalanches in the hilly regions. This parameter is defined as the ratio of the wall shear force to the normal force components of an avalanche. Avalanches are one of the most devastating natural hazards. So, the proper understanding of avalanche flow parameters is vital for the people and the infrastructure in the mountainous regions of the world. Notwithstanding the utmost significance of the Coulomb friction parameter, a few measurements are available for this parameter. In the present work, based on 32 measurements carried out from 2017 to 2020, a new database for the shear force and normal force components of the avalanches and derived values of the dynamic coefficient of friction between the chute steel surface and the flowing snow are presented. The measurements were carried out using a three-component piezoelectric load cells-based dynamometer which in turn was installed on the 12° slope of a 61-m long snow chute, located in the Pir Panjal Himalayan range of India. Based on all the measurements, the average value of the dynamic coefficient of friction for snow-steel surface is estimated to be 0.113 with a standard deviation of 0.032. The results have been exhibited to be in accordance with the published literature. It is expected that the present database will be highly significant for the validation and improvement of avalanche dynamics models especially for high-density wet snow conditions. Further, shear force and normal force components data may be useful for the designing of snow sheds in mountainous regions.

The proliferation of urban sprawl has emerged as a prevalent occurrence in response to the rapid expansion of the worldwide population. The objective of this study is to determine the level of freedom for urban expansion using Pearson’s Chi-square (χ 2 ) index and the amount of urban spatial dispersion using the Shannon entropy ( H n {H}_{n} ) index in Hue City, Vietnam. While the first index asserts the degree of freedom for observed urban growth above expected urban growth, the second index is applied to analyze urban spatial dispersion patterns through richness and evenness. Land use map data were collected from Japan’s JAXA agency from 1990–2020. Research results show that, in the past 10 years (2010–2020), the level of urban freedom expansion in Hue city has increased compared to the period 2000–2010 and 1990–2000, with corresponding χ 2 values of 219.18, 150.05, and 106.95. The South-Southwest (TNN) area is also the area with the most significant urban freedom expansion among the eight regions in Hue City through three stages. The urban dispersion level in Hue City has also expanded recently when the H n {H}_{n} and H n ′ {H}_{n}^{^{\prime} } indexes gradually increased from 1990 to 2020. This result puts pressure on the Hue city government on how to develop the city sustainably. Therefore, the study also points out some disarmament to contribute to sustainable urban development.

Naqadeh Region (NR) is one of the most sensitive regions regarding geo-hazards ‎occurrence in Northwest of Iran. The landslides triggering parameters that ‎identified for the studied region are classified as elevation, aspect, slope angle, ‎lithology, drainage density, distance to river, weathering, land-cover, ‎precipitation, vegetation, distance to faults, distance to roads, and distance to ‎the cities. These triggering factors are selected based on conducting field ‎survey, remote-sensing investigation, and historical development background ‎assessment. Regarding the investigations, 12 large-scale, 15 medium-scale, and 30 small-scale historical landslides ‎(57 in total) were recorded in the NR. The historical landslides were used to provide ‎sensitive area with high probability of ground movements. The objectives of this study are multifaceted, aiming to address critical gaps in understanding and predicting landslide susceptibility in the NR. First, the study seeks to evaluate and compare the effectiveness of ‎support-vector machine (SVM), multilayer perceptron (MLP), and decision tree ‎‎(DT) algorithms in predicting landslide susceptibility. So, as methodology, the ‎presented study used comparative models for landslide susceptibility based on ‎SVM, MLP, and DT approaches. The predictive models were compared based on model ‎accuracy as the area under the curve of the receiver operating characteristic ‎curve. According to the estimated results, MLP is the highest rank of overall ‎accuracy to provide susceptibility maps for landslides in NR. From a perspective of ‎the risk ability, the west and south-west sides of the county were identified within ‎the hazard area.

Shear strengths of silty soil were determined for shallow destruction of the soil sites frequently occurring in the Central Plains area. Specimens were prepared with five different clay contents (5, 10, 15, 20, and 25%) prior to compaction at dry densities of 1.60, 1.70, and 1.80 g/cm 3 . Soil specimens were saturated and then the consolidated undrained shear test was conducted with eight confined pressures ranging from 1 to 400 kPa. Results indicate that the shear strength increases significantly as the clay content increases from 5 to 25%, and the cohesion c shows bilinear function with the inflection point at the clay content of 10%. The difference of cohesion in the high and low stress sections decreases gradually to almost the same value until 25% of the clay content, while the internal friction angle φ decreases with the increase in clay content. Within the range of dry density and clay content tested, the shear strength of silty soil in the low stress range obtained is higher than the measured value. Therefore, for the shallow damage of soil site, the shear strength parameters should consider the low stress test conditions. The bilinear growth of cohesion c with clay content can be attributed to the changes from “sand-like soil” to “clay-like soil” with the skeleton of soil specimen transitioning from sand particles to “clay grid” when the clay content exceeds approximately 10% combined with the results of scanning electron microscopy.

Babušnica is one of the poorest municipalities in Serbia. Although it is a region with excellent physical geographic features that support the development of recreational and environmentally conscious types of tourism, its natural resources are almost entirely underutilized. The article first discusses Babušnica’s primary development issues before doing a theoretical examination of the ideas of geotourism and sustainable tourism and applying the Modified Geosite Assessment Model. To investigate the potential for their tourism activation, nine geosites were selected and evaluated. The evaluation ratings for most of the sites are very low due to the absence or poor quality of each type of infrastructure. The types of tourism that can be promoted in the region according to its geographical features are identified and recommendations are made to local and higher levels of authority that could form the basis for sustainable growth of the region.

The importance of site selection for road transportation management and emergency services has been underscored, particularly in the wake of the global Covid-19 pandemic in addition to road accident injuries, which emphasized the need for swift patient, injured and wounded peoples transfer to hospitals. As a result, comprehensive road transportation management is essential during crises to ensure the safety and convenience of road users. To achieve effective road network management, a robust database is imperative. The aim of this study is to employ multi-criteria decision analysis with the aid of Geographical Information System (GIS) technology and remote sensing for the optimization of site selection for traffic signals, fire stations, and emergency services in Kafr El-Sheikh city, Egypt. The methodology incorporates two different methods which are Fuzzy Analytical Hierarchy Process (F-AHP) and the spline transformation method. The integration of Fuzzy set theory with AHP principles has given rise to a variant of AHP known as F-AHP. F-AHP combines qualitative and quantitative approaches. Fuzzy logic handles situations that are vague or poorly defined by assigning numerical values. Through the F-AHP approach, criteria that decision-makers unanimously deem “absolutely not important” in comparison to others are eliminated, allowing them to focus on the most significant criteria. As a case study, an Egyptian city was selected to apply these techniques. The results revealed multiple sites that were identified and selected through the applied analytical methods. These selected sites were also marked on the city map and verified in reality.

Many multi-types of unconventional oil and gas reservoirs have been found in some faulted basins in northern China, showing good exploration potential. However, the hydrocarbon accumulation mechanism in these areas is still unclear, which limits the understanding of the distribution of oil and gas. In this study, we took Hari Sag in Yin’e Basin as an example, conducted a systematic analysis on various types unconventional oil and gas reservoirs, and revealed its characteristics and accumulation mechanisms. The study showed that there were many types of unconventional oil and gas reservoirs in Hari Sag, such as biogas reservoirs, shale gas reservoirs, shale oil reservoirs, tight sandstone oil reservoirs, tight sandstone gas reservoirs, and volcanic gas reservoirs. These reservoirs generally had characteristics of “near/within source rocks accumulation,” “coexistence of oil reservoirs and gas reservoirs,” “shallow oil and deep gas,” and so on. Research on the mechanism of hydrocarbon accumulation showed that: the lack of effective hydrocarbon migration pathway was the main reason for “near/within source rocks accumulation” of oil and gas reservoirs; the differences in the thermal evolution degree of the main source rocks at different structural positions in the sag made the distribution characteristics of hydrocarbon as “coexistence of oil reservoirs and gas reservoirs” and “shallow oil and deep gas”; and the joint development of multi-type effective unconventional reservoirs created the situation of “coexistence of multi-type unconventional oil and gas reservoirs.” It is predicted that six types of unconventional oil and gas reservoirs have a cumulative area of 381 km 2 , indicating that the Hari Sag has great potential for unconventional oil and gas exploration. The research results can not only guide the unconventional oil and gas exploration in Hari Sag but also provide a theoretical basis for exploration research in similar blocks.

The total organic carbon (TOC) content is an important index for source rock evaluation. However, due to the scarcity of rock samples, the vertical continuous TOC change curve cannot be obtained, and the test cost is high, which bring great limitations to the evaluation of source rocks. Predecessors have also studied some TOC prediction models, such as the Δlg R method, support vector regression (SVR), and back-propagation neural network, but the TOC predicted by the Δlg R method and SVR has low accuracy and is difficult to calculate. However, back-propagation neural networks always have problems such as local optimal solution and slow convergence speed. In this article, a convolution neural network prediction scheme is proposed. Taking the source rocks of Pinghu Formation in the Xihu Sag as the research object, the advantages of this method are proved by comparing the prediction results of the Δlg R method, SVR, and BP neural network method. The results show that the prediction accuracy of this method is more than 90%, meeting the prediction requirements of TOC. By predicting the TOC curve of Well A, the TOC variation characteristics of Pinghu Formation are finally obtained.

The wind power industry is increasing worldwide every year. Thus, obtaining timely and detailed information on wind farms’ number and spatial distribution is critical for quantitatively estimating wind energy utilization and for planning the construction of new wind farms. Therefore, this study proposes a method for quickly identifying wind farms in a large-scale area. Given that wind farms mainly comprise individual objects such as wind turbines and substations, we labeled sample images of wind turbines and substations on a global scale. Then, these sample images are used to train a target recognition model and an object classification model and detect the specific locations of wind turbines and substations in the study area. Additionally, we deeply analyzed the location features of the wind turbines and further improved the recognition accuracy based on these known features using geographic constraints. Based on the location information of wind turbines and substations, a clustering model organizes them effectively into complete wind farms. A comprehensive evaluation of the clustering model verifies its scientific validity and reliability. Specifically, this framework was systematically tested throughout Vietnam with remarkable results, using high-resolution historical images provided by Google Earth. Indeed, our framework achieved 90.45% recall and 95.73% accuracy for wind turbines and 81.37% recall and 78.96% accuracy for substations. Finally, we successfully obtained the spatial location and distribution of 15 completed wind farms, demonstrating that the proposed scheme can quickly and accurately identify wind power plants in a large-scale area, which supports wind power management and energy utilization planning.

Rocky desertification is a pressing environmental concern in Southwest China, and it significantly impacts local living conditions and regional sustainability. Employing remote sensing on a macro scale, this study focuses on identifying and analyzing the spatial distribution and driving factors of rocky desertification. Conducted in Southwest China, using Landsat data from Google Earth Engine, the research quantitatively extracts information on rocky desertification patches through spectral analysis methods. We investigated the spatial distribution characteristics and driving factors of rocky desertification through geographic information system spatial analysis and a geodetector model. The main conclusions are as follows. The area of rocky desertification in Southwest China covers 217530.4 km² (accounting for 15.6% of Southwest China), with areas of slight, moderate, and severe rocky desertification at 81.3, 7.1, and 11.6%, respectively. Spatially, rocky desertification is primarily distributed in areas where lithology is carbonate rock between clastic rocks and continuous limestone, slope exceeds 15°, elevation range is 1,000–2,000 m, land use types are grassland and woodland, precipitation is 80–120 mm, and population density is below 50 people/km². Human activities have a minimal influence in comparison to natural factors. Geodetector analysis identifies lithology, land use types, and slope as primary driving factors, with interactive effects of lithology and land use type and slope and land use type jointly influencing rocky desertification formation in Southwest China. The results of the study provide a scientific basis for an in-depth understanding of rocky desertification in Southwest China and for the management of rocky desertification.

This study is focused on the evaluation of the geophagic characteristics of the sedimentary clay deposits at Share and Tshonga areas, northern Bida Basin, Nigeria. The methods used include particle size distribution, cation exchange capacity (CEC), acidity and alkalinity (pH), X-ray diffractometry, and bulk inorganic geochemical analysis (X-ray fluorescence and inductively coupled plasma mass spectrophotometer). The investigated clays are classified as dominantly clayey–silt with minor clayey–sand type, which conforms with the textural standard of geophagic clays obtained from different parts of the world. The whitish coloration of the clays with an occasional red stain also compares well with geophagic clays from Kenya and parts of South Africa and is therefore considered suitable for consumption. The observed low CEC (1.71–5.06 cmol(+)/kg) and acidic pH (4.54–6.87) values of the clay samples would make them effective against nausea and excessive salivation during pregnancy. The mineralogical compositions of these clay samples show the dominance of kaolinite with minor non-clay minerals, which makes it suitable not only for food detoxification but also as an alleviation of gastrointestinal disorders such as diarrhea. Chemical analysis shows a low percentage per weight of certain elements that are of nutritional value, though not in the present state but better as excipients in the pharmaceutical industry. It was observed, however, that consumption of more of the studied clay may lead to adverse health due to the presence of some heavy metals (Co, Cu, Ni, Cd, Ag, and Pb) with concentrations in excess of the permissible limit.

Chaohu Lake is a representative lake in China that suffers from severe eutrophication and algal blooms. Understanding the changes in the lake’s eutrophic condition over time is essential for its restoration and management under the background of global changes and regional sustainability. In this context, the compositions of carbon and nitrogen isotopes ( δ 13 C org and δ 15 N, respectively), total organic carbon (TOC), total nitrogen (TN), and carbon–nitrogen ratio (C/N) were analysed to depict the history of eutrophic state of Chaohu Lake, and its relationship with environmental changes. The result show that before the 1950s, the primary productivity of the lake was low. During the period from the 1950s to the 1970s, primary productivity increased substantially due to eutrophication. From the 1970s to the present, as a result of the construction of the Chaohu Floodgate Station, water replacement in the semi-closed Chaohu Lake gradually slowed and nutrients began to accumulate more rapidly. These conditions led to enhanced lake productivity and rapid eutrophication, mainly caused by intensified human activities and increased exogenous inputs. Our findings suggest that the geochemical records ( δ 13 C org , δ 15 N, TOC, TN, and C/N ratios) in sediment for Chaohu Lake are capable of recording important shifts in the temporal evolution of lake-water trophic state.

Freeze–thaw cycles significantly impact resource development and construction projects in alpine regions. This study presents a bibliometric analysis based on the Web of Science database, spanning the period from 2000 to 2023. This analysis evaluates the status of hotspots and research trends in freeze–thaw rock. Our findings reveal that rock freeze–thaw research is a typical multiauthor, multicounty, and multi-institution cooperative field involved in many research fields. China had the highest number (420) of peer-review publications. According to the number of publications, 28 of the top 30 institutions are in China. The top 30 authors, ranked by their publications, contributed 55.4% of the total publications. The cumulative number of publications has presented an exponential increase over the past 23 years, with maximum annual growth rate of 36.9%. The keyword analysis suggests the emergence of modern technological techniques, including numerical simulation, microscopic rock structure analysis, and machine learning, in recent years augment to traditional methods. This article also identifies three potential areas for future research, thereby aiding in understanding the past developments, current status, and future trends of freeze–thaw rock research. Additionally, it provides a theoretical basis for engineering construction and slope disaster management in alpine regions.

Water resource shortage has become an important factor limiting agricultural sustainability in China. In addition, the development and utilization of unconventional water resources are greatly important for alleviating agricultural water resource deficit. The Pakchoi was cultivated by using the surface soil (0–20 cm) from the field in this pot experiment. The experiment lasted for approximately 1 month to study microbial community structure variation under brackish water and reclaimed water irrigation. The 16S rDNA high-throughput assays revealed that soil bacteria mainly consisted of Proteobacteria and Actinobacteria at the Phylum level, along with Arenimonas and Nocardioides at the Genus level under mixed irrigation with brackish water and reclaimed water. In summary, irrigation with pure reclaimed water promoted part of microbial communities and irrigation with pure brackish water inhibited the growth and activities of certain microbial communities. We found that mixed irrigation improved the microbial community structure diversity compared with that in response to pure brackish water irrigation, while decreased the community structure diversity compared with that in response to fresh water irrigation and pure reclaimed water irrigation.

As the value ranges presented in the literature with tables and graphs that feature soil index properties related to the soil swelling potential are intertwined, their interpretation may pose certain challenges. In this study, the spatial distribution maps of soil swelling potential were created using soil index data obtained from this research, and those values of ranges from the swelling potential of the study area were assessed by combining all maps, resulting in a single comprehensive map and new limit ranges in the high plasticity cohesive soils. Soils in the study area were evaluated according to the newly determined limit value ranges. The findings show that the high plasticity cohesive soils in the region should have swelling potential in all parameters of the new limit value ranges to show swelling potential. The limit values for high plasticity cohesive soils to demonstrate a high swelling potential are: % natural water content <18, % passing through #200 sieve >90, liquid limit >65, plasticity index >21, swelling pressure >240 kPa, and % swelling percentage >6.

The genesis and prediction of high-porosity and low-permeability sandstone reservoirs are hot spots in oil and gas geology research worldwide. High-porosity and low-permeability sandstone reservoirs are developed in the Cretaceous Bashkirchik Formation of the Luntai Uplift in the northern Tarim Basin, China. In this article, we conducted a systematic study on the geological origin and logging identification of high-porosity and low-permeability tight sandstone based on core observation, thin section, logging index response, and mathematical discrimination methods. The results show that the K 1 bs sandstone segment in the study area generally contains calcium carbonate, which mainly comes from carbonate rock debris and calcite cement. Calcite cement mainly fills the pores between primary particles, and it is the main factor leading to the densification of the reservoir. The geological origin of the formation of low-permeability layer is mainly due to the early cementation of carbonate, and the development mode of the low-permeability layer is “high content of calcium debris → severe calcium cementation → poor petrophysical properties → formation of low-permeability layer.” The low-permeability layer has the characteristics of high gamma and high resistivity, and the multi-parameter discriminant method established based on the Fisher criterion has a good identification effect for the low-permeability layer. The low-permeability layer has a small thickness, poor stability and continuity, and strong longitudinal heterogeneity, thus it can form a low-permeability baffle inside the reservoir, which greatly reduces the oil and gas migration capacity.

The article explores the usability of the geodiscussion administrative panel, an online tool aiding Public Participation Geographic Information Systems. This tool was specifically designed and developed for distribution in a Software as a service model, offering geodiscussion users the flexibility to leverage the tool without the need for substantial investments in expensive infrastructure or complex deployments. The research primarily centers on the geodiscussion administrative panel, a key component empowering organizers of public consultations in spatial planning to efficiently create and manage consultation processes. In contrast to previous studies that focused on the usability for consultation participants, this research uniquely targets individuals responsible for organizing and overseeing the consultation processes. A diverse array of usability research methods were employed, ranging from the creation of personas and conducting direct interviews based on test scenarios to non-invasive methods for recording user activities. The study involved 682 participants who had prior experience with public consultations across various public administration units and representatives from consulting firms. Given that the usability studies were an integral part of the geodiscussion administrative panel’s development process, the research team has the opportunity to influence the further implementation of the applied functionalities. This implies that insights gained from the research can actively shape and enhance the tool’s features as it progresses in its development cycle.

The Lower Shihezi Formation of the Upper Paleozoic at the northeastern margin of the Ordos Basin develops widely distributed thick massive and multilayer gas reservoirs. How to formulate an effective development policy is a difficult and hot spot. In this article, reservoir characteristics and production capacity influencing factors of the tight gas sandstone in Lower Shihezi Formation in this area are systematically studied, and optimization schemes of development measures for massive and multilayer gas reservoirs are proposed. The results show that the petrophysical characteristics of the small pore–mesopore type gas reservoir in the target layer are the best, with the average porosity, permeability, and coordination number of 7.6%, 0.74 mD, and 3.3, respectively. Thick sand body, high structural position, good petrophysical properties, and high drilling rate of sandstone are all conducive to drilling high production gas wells. Development policies for massive and multilayer gas reservoirs have been formulated: (1) the preferred well type for massive gas reservoir is vertical well + horizontal well, while the preferred well type for multilayer gas reservoir is horizontal well + stepped horizontal well; (2) the reasonable horizontal segment length of massive gas reservoir is 1,000 m, and the reasonable horizontal segment length of multilayer gas reservoir is 1,250 m; (3) similar to massive and multilayer gas reservoirs, the more the fracture stages, the higher the cumulative gas production, and the optimal fracture stage number of both gas reservoirs is 8; (4) the optimal fracture half-length and the angle between the fracture and the horizontal section are 140 m and 90°, respectively; and (5) the reasonable well spacing of vertical wells is 600 m and that of horizontal wells is 750 m. The development policy proposed in this study is suitable for the efficient development of complex tight sandstone gas reservoirs in similar areas.

Natural and climatic features of the soil cover formation of Turkestan region of the Republic of Kazakhstan are identified by a set of hydrological and bioclimatic factors serving as important environment-forming functions, which are reflected in the landscape organization of the territory. When assessing soil resources of agricultural landscapes, integrated index of soil fertility was applied – the “soil index,” which takes into account the reserves of humus, mineral elements, and hydrolytic acidity. Based on monitoring observations (1996–2019) of soil fertility in agricultural landscapes (agricultural lands) of Turkestan region, assessment of soil resources was performed, which showed that in general, the generalized “soil index” ranges from 1.086 to 4.800 units depending on natural features of the territory. It is found that the “soil index” in agricultural landscapes is significantly less than its maximum value (20.000 units), which suggests a pronounced humus deficiency, showing low soil fertility in all agricultural landscapes. To assess the soil resources of agricultural landscapes in Turkestan region, a new approach was applied, which is based on the assessment of energy costs for the soil formation process, which enables to quantitatively reflect the radiation balance of the earth surface, heat, and moisture supply of agricultural land for 1941–1960 and 2001–2020. The indicators applied are subject to the law of vertical zonation and change from the mountain to the arid zone, where the potential energy costs for soil formation range from 82.2–101.9 to 129.4–135.5 kJ/cm 2 , and natural energy costs energy costs for soil formation from 17.2–21.7 to 121.7–125.2 kJ/cm 2 .

Soil resource management is fundamentally integral to environmental sustainability and agricultural productivity. The digital elevation model (DEM) is the fundamental data for analyzing landform surfaces, which introduces an opportunity to obtain a broad spectrum of terrain factors to simplify interpreting the patterns and processes in the geoscience field. The accuracy and resolution of DEM are crucial for their effective use, and many algorithms have been developed to interpolate digital elevation data from a set of known points. Although primary topographic variables derived from grid datasets are important, secondary variables, such as the relief index (RFI), play a more critical role in understanding the complicated relationship between soil properties and landform attributes. The RFI is attained from a DEM by calculating the elevation range within a given neighborhood surrounding a central cell. It is an essential predictor of soil natural resource management that measures the degree of differentiation surface relief. In addition, it is beneficial for perceiving the landscape and its management. This study presents a comprehensive zonal analysis comparing the RFI values derived from multiple interpolation-based DEMs. It investigates deterministic and geostatistical interpolators, such as inverse distance weighted and natural neighbor across distinct zones with diverse topographical characteristics. The findings indicated a high correlation between the RFI and the reliability of the DEM, and the natural neighbor technique provided superior performance against others. The results revealed that the choice of spatial interpolation technique significantly affects the accuracy and reliability of RFI models.

There has been a longstanding debate on whether plutonic and subvolcanic rocks have a petrogenetic connection, and the Jurassic Shuikoushan caldera complex in South China serves as an ideal case study for unraveling this geological puzzle. SIMS U–Pb dating of zircon indicates the formation age of plutonic (granodiorite) and subvolcanic rocks (dacite porphyry and rhyolite porphyry) from the Shuikoushan caldera complex at ca. 159 Ma. In terms of geochemical composition, granodiorite and dacite porphyry exhibit higher levels of MgO (1.98–3.63%), MnO (0.07–0.11%), FeO t (5.12–6.15%), Sr (342–547 ppm), and Ba (754–1200 ppm) compared to the rhyolite porphyry. Conversely, they show lower concentrations of Rb (2.04–27.1 ppm), as well as lower ratios of Rb/Sr (0.004–0.055) and Rb/Ba (0.004–0.023). The distinct but complementary geochemical characteristics between these rock types are evident in the Shuikoushan caldera complex. Overall, zircon grains from all three rock types exhibit similar negative ε Hf ( t ) values (–8.1 to –12.4) with high δ 18 O values (8.3–9.7‰), suggesting a common source region. Based on lithological and geochemical evidence, it is proposed that the rhyolite porphyry represents extracted melt from the mush reservoir. In contrast, the granodiorite and dacite porphyry are residual melts enriched in cumulates. This interpretation supports the idea that crystal–melt segregation processes were crucial in connecting the late Jurassic subvolcanic and plutonic rocks within the Shuikoushan complex.

The identification of shale lithology is of great importance for the exploration and development of shale reservoirs. The lithology and mineralogical composition of shale are closely related, but a small number of laboratory core analysis samples are insufficient to evaluate the lithology of the entire formation. In this study, a lithology identification method using conventional logging curves is proposed for the shale stratigraphy of the Qingshankou Formation in the Gulong Depression of the Songliao Basin, northeastern China. First, a mineral pre-training model is constructed using discrete petrophysical experimental data with logging data, and features are generated for the logging data. Second, an adaptive multi-objective swarm crossover optimization method is employed to address the imbalance of logging data. Finally, the model is combined with a Bayesian gradient boosting algorithm for lithology identification. The proposed method demonstrates superior performance to eXtreme Gradient Boosting, Support Vector Machines, Multilayer Perceptron, and Random Forest in terms of accuracy, weight perspective, and macro perspective evaluation indexes. The method has been successfully applied in actual wells, with excellent results. The results indicate that the workflow is a reliable means of shale lithology identification.

In recent years, studying dolomite diagenesis and controlling factors of reservoir development from microscopic perspective has become a hot subject in deep carbonate gas exploration. In this study, we have carried out a fine classification of different types of dolomite reservoirs in the Fei-3 Member of the Lower Triassic Feixianguan Formation in the Puguang area, and the distribution law and main controlling factors of dolomite reservoirs have been clarified. The results show that the dolomite reservoirs of the Fei-3 Member in the Puguang area include three rock types: residual structure dolomite, microbial dolomite, and crystalline dolomite, and the main reservoir space types are intergranular pores, solution pores/caves, and inter-crystalline pores, respectively, and the solution fractures are mainly developed in the residual structure and microbial dolomites. Most of the dolomite reservoirs are distributed in the Fei 3 1 sub-member, and the residual structure dolomite is mainly distributed in the relative paleomorphic highs of the Fei 3 1 sub-member; microbial dolomite is mainly developed in the platform environment with shallow water and intermittent exposure, and is controlled by the growth conditions of microorganisms; the crystalline dolomite is mostly distributed in the relatively shallow water and relatively limited dolomite flat environment. On the plane, the dolomite reservoirs are distributed in the form of clumps. The distribution of residual structure dolomite reservoir is controlled by paleotopography and early exposure corrosion. Microbial dolomite is formed in the microbial mat microfacies, and the distribution range of microbial mat controls the development of microbial dolomites. The diagenetic types of the dolomites in the target layer include dolomitization, dissolution, rupture, and material filling. Various kinds of pores formed by syngenetic dissolution provide channels for later buried dissolution, and organic acids formed by organic matter maturation under deep burial conditions play a crucial role in dissolution of dolomite and promote the formation of dissolution pores. In the burial stage, hydrocarbons enter the dolomite, which can effectively prevent the growth of late authigenic minerals, thus promoting the preservation of pores. The structural fracture system formed by late tectonic movement can communicate with different pore groups and improve the reservoir quality.

High-speed railway (HSR) networks have profoundly influenced interregional accessibility and economic linkages. This study examined 100 counties (cities) and districts in Jiangxi Province, using spatial and temporal data to measure weighted average travel time, daily accessibility, the accessibility coefficient, and the total and intensity of economic linkages. This study analyzed the impacts of operating a single HSR line versus an entire network. The findings revealed that (1) the HSR network has created a balanced spatial–temporal convergence effect, narrowing the gap between most locations and showing a clear “corridor effect”; (2) the network has strengthened economic connections among counties and has significantly enhanced overall economic output by creating two high-level economic linkage belts, formed around the Shanghai–Kunming and Beijing–Hong Kong HSRs; and (3) the network amplifies the “Siphon effect” and “Matthew effect,” further disadvantaging non-connected regions. Therefore, the province should promote a well-designed, HSR network, enhancing economic exchanges among counties and fostering a high-level economic belt characterized by diversity, complementary advantages, and coordinated development.

An accurate survey of field vegetation information facilitates the evaluation of ecosystems and the improvement of remote sensing models. Extracting fractional vegetation cover (FVC) information using aerial images is one of the important areas of unmanned aerial vehicles. However, for a field with diverse vegetation species and a complex surface environment, FVC estimation still has difficulty guaranteeing accuracy. A segmented FVC calculation method based on a thresholding algorithm is proposed to improve the accuracy and speed of FVC estimation. The FVC estimation models were analyzed by randomly selected sample images using four vegetation indices: excess green, excess green minus excess red index, green leaf index, and red green blue vegetation index (RGBVI). The results showed that the empirical model method performed poorly (validating R 2 = 0.655 to 0.768). The isodata and triangle thresholding algorithms were introduced for vegetation segmentation, and their accuracy was analyzed. The results showed that the correlation between FVC estimation under RGBVI was the highest, and the triangle and isodata thresholding algorithms were complementary in terms of vegetation recognition accuracy, based on which a segmentation method of FVC calculation combining triangle and isodata algorithms was proposed. After testing, the accuracy of the improved FVC calculation method is higher than 90%, and the vegetation recognition accuracy is improved to more than 80%. This study is a positive guide to using digital cameras in field surveys.

The Mélange in Lamphun Province, situated in the southern region of the Chiang Mai-Chiang Rai Suture Zone (CMCRSZ), remains inadequately explored. This study employs field investigations and petrographic analysis to delineate the characteristics of the CMCRSZ Mélange, identifying nine distinct rock units. These units include Carboniferous quartz arenite interbedded with fine-grained sedimentary rocks, Permian lithic graywacke, Permian limestone hosting Pseudodaliolina sp. and Schwagerinid sp., Triassic chert containing Anisian radiolarian fossils, and ocean island basalt. This area exhibits complex folding and thrusting, accompanied by granitic intrusions and low-grade metamorphic rocks within a finer-grained sedimentary matrix. Stratigraphic assessments trace the primary material of the accretionary complex to the upper strata of the oceanic plate stratigraphy. Geochemical analyses indicate the mafic rocks as alkaline to subalkaline basalts, indicative of formation through an alkaline magma series, a conclusion supported by rare-earth element patterns. Sr/Nd isotope classification suggests ocean island tectonics for these rocks. The formation of the CMCRSZ Mélange occurred during the Paleo-Tethys oceanic crust subduction beneath the Indochina Terrane at the Permian-Triassic Boundary, accumulating diverse materials in a dynamically evolving tectonic context. Furthermore, S-type Triassic granites emerged post-collision during the Indosinian Orogeny following the thrusting of the CMCRSZ onto Sibumasu.

The study of tectonic activity holds great significance in assessing historical and modern seismic risks. The Weihe Graben is a significant intracontinental graben system in China, with numerous active faults that have caused a series of earthquakes, including the Huaxian great earthquake ( M ∼ 8.5) in 1556 with approximately 830,000 deaths. Despite the obvious spatial relationship between the Weihe fault (WF) and these earthquakes, detailed research on the fault is still lacking. Various techniques including remote sensing images, digital elevation model, shallow seismic lines, trench excavation, drilling sections, and optically stimulated luminescence dating, have been utilized to obtain the following results: (1) The WF passes through the scarp of the Weihe River terrace in the north of Xianyang and can be divided into east and west sections at Jinjia village; (2) The WF is a normal fault that strikes northeast and dips south with a dipping angle of 65°–75°; (3) The fault has been active during the Holocene; (4) The vertically offset and dating results suggest that the fault activity has gradually decreased since the late Pleistocene, and the vertical slip rate during the Holocene is only 0.04–0.13 mm/year.

In the southwestern Sichuan Basin, the Jurassic Shaximiao Formation encompasses a multitude of working areas, displaying intricate sedimentary traits. Traditional methods of stratigraphic division based on sequence suffer from inherent subjectivity and limitations. This study employs a combined mathematical approach to use the wavelet transform (WT) and the Hilbert–Huang transform (HHT). It decomposes the natural gamma ray (GR) logging curve into energy spectrum plots and wavelet coefficients at different scales, high and low frequency signals at different frequencies, and a set of intrinsic mode function components and residual functions. The study conducted a detailed stratigraphic division of the Jurassic Shaximiao Formation in the southwestern Sichuan Basin using these methods. The WT offers greater resolution for the periodic changes in the base level, whereas the HHT demonstrates a superior correlation with the positions of stratigraphic interfaces. The combined utilization of the continuous wavelet transform, the discrete wavelet transform, and HHT methods has demonstrated encouraging outcomes in the stratigraphic division of the Jurassic Shaximiao Formation. These methods have been shown to enhance the accuracy of stratigraphic division and to reduce the influence of subjective factors. This study presents new insights and approaches for geological data processing, offering significant theoretical and practical implications and novel technical means for oil and gas exploration and development.

In order to reveal the restriction in shale gas enrichment of the Wufeng-Longmaxi Formation in the northern Guizhou province, the influence model of detachment layer was established through field geological investigation, core observation, logging, sample analysis, and geological background data. The response relationship between the detachment layer and the shale gas enrichment model in different structural formats was analyzed. The results show that the thickness of the Wufeng-Longmaxi Formation’s detachment layer is influenced by the conditions near the fault zones and mineralogical characteristics. The lithofacies of the detachment layer shows mainly a combination of clay-rich shale facies. This indicates that lithofacies type is one of the main factors influencing the variation in slip layer thickness. The detachment layer exhibits distinct well logging response characteristics and is influenced by nitrogen enrichment. The development of detachment fractures allows atmospheric nitrogen to infiltrate shale gas. It leads to poor gas saturation in the shale gas. In addition, the overall tectonic deformation in the northern Guizhou province was found to gradually intensify from Northwest to Southeast, and there were two tectonic models: a slot-shift tape transition belt and a spacer type deformation belt. The influence of decollements on shale gas preservation was barely found in the northern Guizhou province. It is mainly controlled by buried depth of the target layer, conditions of the cover layer, structural type, and deformation intensity.

Fine characterization of oil plane distribution in highly heterogeneous tight sandstone is a prerequisite for efficient reservoir development. This study systematically evaluated the distribution characteristics of tight oil in the Chang 7 Member of the Western Ordos Basin using a large number of experimental tests, logging interpretation, and 3D modelling methods. The logging interpretation models of shale content, porosity, permeability, and oil saturation were constructed, and the effective reservoir was identified by establishing the intersection identification pattern of reservoir acoustic wave time difference and deep lateral resistivity. The 3D numerical simulation results showed that the tight oil is distributed between injection and production wells. The areas with high tight oil content are mainly distributed along the WE direction, and a series of high remaining oil zones are formed locally. Under the influence of long-term injection and production, a high permeability zone will be formed between wells, which is similar to a high-speed channel and will be flooded quickly, and a banded remaining oil retention zone will be formed around it. For the horizontal well flooding area, the water flooding range of the water injection well is small, and a large amount of remaining oil is enriched between water injection wells. Finally, the classification standard of the remaining oil in the Chang 7 2 sub-member of the study area is proposed, and then, the strategy of adopting different development and adjustment schemes according to different types of reservoirs is formed.

This study determines the mineralogical, petrographical, and geochemical properties of the rocks outcropping in geothermal areas west of the Cappadocia geothermal region. These areas include Ziga, Narlıgöl, Belisırma, Ilısu, and Sivrihisar. The study reveals their hydrothermal alteration characteristics. Also, the study aims to determine the zones of hydrothermal alterations using remote sensing. Rock samples from geothermal areas were performed using optical microscopy, X-ray diffraction (XRD), scanning electron microscopy, X-ray fluorescence spectroscopy, and inductively coupled plasma–mass spectrometry techniques for the determination of mineralogical assemblages and major, trace and REE's analyses. Rock samples, determined as ignimbrites and tuff, exhibit intensive alterations. XRD analysis determined the association of alteration minerals. The dominant clay minerals were kaolinite, montmorillonite, and illite. The analyses and mineral associations are compatible with argillic, mid-argillic alteration, and silicification zones. Alteration zones were identified by classifying the ASTER satellite images of kaolinite, illite, and montmorillonite using the CROSTA technique. The alteration zones observed in this study are close to existing geothermal areas. In addition, different regions with these alterations have been identified within the study area and are expected to be a valuable reference for future geothermal exploration.

Site response analyses at large strains are routinely carried out neglecting the shear strength of soil and the stiffness degradation due to the increase in pore pressures, leading to unrealistic predictions of the seismic response of soil deposits. The study investigates the performance of a simplified nonlinear (NL) approach, implemented in the Deepsoil code, constituted by coupling a hyperbolic model incorporating shear strength with a strain-based semi-empirical pore pressure generation model. The first part of the study, based on a large one-dimensional parametric study, shows that above a shear strain of 0.1%, it is necessary to include shear strength in the site response modelling to get more realistic results. Then, the approach has been evaluated with reference to the well-known downhole Large-Scale Seismic Test array located in Lotung (Taiwan): numerical results have been compared with recordings in terms of acceleration response spectra and pore water pressure time histories at different depths along the soil profiles. The comparison shows that the NL simplified model is characterized by an accuracy comparable with more sophisticated advanced elasto-plastic NL analyses adopting essentially the same input data of the traditional equivalent linear approaches(shear modulus and damping curves) and simple physical-mechanical properties routinely determined during geotechnical surveys (i.e., shear strength, relative density, fine content). This approach is therefore recommended for site response analyses reaching large strains (i.e., soft soil deposits and moderate-to-high input motions).

Quantitative evaluation of rock dynamic disaster intensity is a challenging and difficult task in the field of earth science. In this article, the dynamic compression tests of granite under different impact velocities are carried out, and the energy evolution characteristics of the dynamic failure process of granite are analyzed. The dynamic fracture characteristics of granite were studied by using computed tomography and section scanning equipment. The results show that the energy dissipation and energy accumulation mechanism of granite under dynamic loading are fundamentally changed with the increase of impact disturbance strength, which leads to the transformation of the failure mode from the tension-type sheet crack under low-speed impact to the complex network crack coupled by tension and shear under high-speed impact. At the same time, the greater the impact velocity, the larger the macroscopic crack density, the more uneven the particle distribution on the fracture section, the greater the roughness, and the higher the rock mass fracture degree. In accordance with the results, the energy distribution ratio is proposed to quantitatively characterize the coupling effect of energy dissipation and energy accumulation in the dynamic failure process of granite and to reflect its dynamic failure intensity. The higher the energy distribution ratio, the stronger the energy coupling effect and the more intense the dynamic failure of the rock mass.

Debris flow is one of the most common types of geological disasters in China. Owing to the influence of topography, geomorphology, geological conditions, human activity, and rainfall debris flow disasters frequently occur in the mountainous areas of Beijing. The research on debris flow in the Beijing area focuses on rainfall and risk evaluation, material sources, and early warning and prevention of debris flow. However, there are few studies on the development characteristics of single-gully debris flow and the prediction of hazardous areas in the Beijing area. Therefore, we chose the debris flow of Bangou Village in Yanqing District of Beijing as the research object. We analyzed the recharge conditions in the ditch domain and predicted the extent of the hazardous area around the gully, providing suggestions for control measures. The dynamic reserves of the loose deposits in the debris flow gully, currently in the development stage, were estimated as 15.48 × 10 4  m 3 , representing four supply sources: artificial deposits, alluvium and diluvium, residual slope deposits, and collapse. The peak flow is 24.49 m 3 /s for a 10-year rainfall event, 27.64 m 3 /s for a 20-year rainfall event, 31.79 m 3 /s for a 50-year rainfall event, and 34.93 m 3 /s for a 100-year rainfall event. The total amounts of solids washed out by a debris flow from the preceding events are 0.70 × 10 4  m 3 , 0.79 × 10 4  m 3 , 0.91 × 10 4  m 3 , and 1.00 × 10 4  m 3 , respectively. The size of the debris flow is small, with a maximum hazardous area of 0.2810 km 2 . We conclude that a small debris flow outbreak in the Bangou Village gully is possible. We expect that the results of this study will provide basic information and help improve debris flow research in Beijing.

This study aims to develop a comprehensive method for automated rockfall mapping and susceptibility assessment using unmanned aerial vehicle (UAV) tilt photography and the support vector machine (SVM) algorithm. By employing Jinzhong Town in the mountainous forest landscapes of Southwest China as a case study, we leverage photogrammetry principles and computer vision algorithms to generate high-precision, high-resolution digital surface models (DSMs), and digital orthophoto maps through a UAV remote sensing system. The rockfall inventory is accurately and automatically mapped using the object-based classification method and SVM algorithm. The automated rockfall identification method achieves a 93% accuracy with a Kappa coefficient of 0.7967. Statistical analyses of spatial distribution characteristics reveal a significant correlation between rockfall volume and area with a correlation coefficient ( R ²) of 0.92316 under logarithmic coordinates. In addition, a power function relationship describes the link between rockfall volume and slope height ( R ² = 0.87), while the relationship with sliding distance is characterized by a weaker linear correlation ( R ² = 0.65). Rockfall runout distance also shows a significant linear correlation with slope height ( R ² = 0.79) but exhibits a less-pronounced association with rockfall volume ( R ² = 0.58). The SVM model employed to assess rockfall susceptibility indicates high accuracy (area under the curve = 0.896), affirming its efficacy in rockfall susceptibility assessment. Our findings underscore the utility of UAV remote sensing for rockfall information extraction and susceptibility evaluation, particularly in challenging mountainous forest environments characterized by intricate topography and geological complexities.

Traditional photogrammetry techniques require the use of Ground Control Points (GCPs) to accurately georeference aerial images captured by unmanned aerial vehicles (UAVs). However, the process of collecting GCPs can be time-consuming, labor-intensive, and costly. Real-time kinematic (RTK) georeferencing systems eliminate the need for GCPs without deteriorating the accuracy of photogrammetric products. In this study, a statistical comparison of four RTK georeferencing systems (continuously operating reference station (CORS)-RTK, CORS-RTK + post-processed kinematic (PPK), RTK + dynamic RTK 2 (DRTK2), and RTK + DRTK2 + GCP) is presented. The aerial photo was acquired using a Dà-Jiāng Innovation Phantom 4 RTK. The digital photogrammetric processing was performed in Agisoft Metashape Professional software. A pair of global navigation satellite systems (GNSSs) receiving antennas model CHC x900 were used for the establishment of check points (CPs). The accuracy of photogrammetric products was based on a comparison between the modeled and CP coordinates. The four methods showed acceptable planimetric accuracies, with a root mean square error (RMSE) X,Y ranging from 0.0164 to 0.0529 m, making the RTK-CORS + PPK method the most accurate (RMSE X,Y = 0.0164 m). RTK-CORS + PPK, RTK-DRTK2, and RTK-DRTK2 + GCP methods showed high altimetric accuracies, with RMSE Z values ranging from 0.0201 to 0.0334 m. In general, RTK methods showed a high planimetric and altimetric accuracy, similar to the accuracy of the photogrammetric products obtained using a large number of GCPs. Graphical abstract

Rainfall–runoff modeling is essential for the hydrological analysis of basins; however, the traditional modeling approach does not incorporate geological features such as fractures and fissures in the modeling task. These features are significant in the water loss during a rainstorm, which should be incorporated to obtain realistic rainfall–runoff results. A novel approach is presented here in to quantify the geological features and link them to the curve number (CN) method. The proposed methodology has not been applied in the literature. This approach is validated on five gauged basins, namely, Yiba, Al Lith, Liyya, Habawnah, and Tabalah, in the southwest part of Saudi Arabia. Four major stages are conducted. The first stage is the extraction of the geological lineaments using remote sensing and geographical information system technology; the second stage is estimating CN from rainfall–runoff data; the third stage is developing a relationship between CN and lineament density (LD); and the final stage is evaluating the developed equations on hydrological response. The least-squares method is employed to minimize the difference between observed and predicted runoff and determine the optimum range of CN. The research provides a comprehensive understanding of hydrological processes in fractured geologic systems and explores the influence of fractures on curve number. This study identifies two major lineament trends aligned with the Arabian trend direction, namely, north-northwest (NNW)–south-southeast (SSE) and north-northeast (NNE)–south-southwest (SSW). Furthermore, a moderate inverse correlation is established between LD and CN, highlighting the significance of geologic fractures on the hydrological response. The findings of this study provide insight into how the geological fissures in the mountainous region affected the rainfall–runoff response that leads to a low value of CN due to the water loss in the fissures and faults. As a result, this study clearly demonstrates the importance of the geological structures on rainfall–runoff responses.

The Ntega-Marangara area, part of the Kanyaru supergroup, Western Domain of Karagwe Ankole Belt, hosts numerous pegmatite veins related to the leucogranite. This investigation aims to characterise the granitoids, their alteration products, and rare metal mineralisation potentials. Quartz, plagioclase, microcline, albite, and muscovite are the essential minerals in both the pegmatite and leucogranite. The ΣREE of the pegmatite and leucogranite are 147 and 102 ppm, respectively. The greisen with Rb, Cs, Ta, Li, Nb, and Sn of 5,940, 1,015, >2,500, 130, 1,595, and 671 ppm, respectively, is higher than the corresponding values of 636, 62, 32, 74, 58, and 110 ppm of the kaolinised pegmatites. This enrichment classifies them as lithium–caesium–tantalum pegmatite. The mean K/Rb, K/Cs, and Nb/Ta in the leucogranites are 106.86, 2819.24, and 4.30, pegmatite is 35.33, 469.47, and 3.1, and greisen is 14.05, 82.2, and 0.64, respectively, which suggest that greisenisation due to metasomatic reactions of late hydrothermal activity could have increased the potential for rare metal mineralisation of the altered pegmatite. Pegmatite of Ntega-Marangara area is enriched in LREE relative to HREE with K/Rb ratio <100, indicating a high level of fractionation and mineralisation in Ta–Nb, Sn, and Li in contrast to the leucogranite that is less fractionated and barren.

Clearly determining the magnitude of fracture pressure is a crucial indicator for fracturing design. Traditional methods for predicting fracture pressure suffer from challenges such as difficulties in obtaining required data, low prediction accuracy, and local limitations in application. In light of these issues, the article proposes a fracture pressure prediction model based on reinforcement learning and XGBoost utilizing geophysical well logging data. Based on the relevance analysis, optimal input parameters, including DEPTH, DEN, AC, GR, CRL, and RT, are selected from geophysical well logging data. We have developed a framework for a fracture pressure prediction model based on XGBoost, wherein hyperparameters are fine-tuned using an improved Q -learning algorithm. The optimized XGBoost model for fracture pressure prediction attains outstanding performance metrics, including an R 2 value of 0.992, a root mean square error of 0.006%, and a mean absolute error of 0.539%. In direct comparison with grid search, Bayesian optimization, and ant colony optimization, the improved Q -learning algorithm emerges as the most effective optimization approach. The predictions generated by the proposed method exhibit remarkable consistency with fracture pressure data measured on-site. This approach successfully addresses the shortcomings encountered with traditional fracture pressure prediction methods, such as inadequate accuracy, demanding data prerequisites, and constrained applicability.

Based on probabilistic seismic hazard analysis, the seismic landslide hazard research considers the spatial and temporal distribution characteristics of seismic peak ground acceleration, which integrates the factors such as seismic intensity, location, and recurrence time. The occurrence of future earthquakes has certain randomness. This article presents the landslide hazard zoning of the eastern Kunlun fault zone and its surrounding faults, which is carried out under the action of horizontal ground motion with certain exceeding probability. According to the geological structure and seismicity characteristics of the study area, the potential source is divided. Based on the seismic hazard analysis and Newmark cumulative displacement evaluation model, the seismic landslide hazard in the study area is analyzed. The landslide probability is taken as the risk index. The seismic landslide hazard can be divided into five grades: extremely low-prone area, low-prone area, medium-prone area, high-prone area, and extremely high-prone area. In the results of seismic landslide risk zoning given in this article, the surrounding areas of Tazang fault and Minjiang fault are high-risk areas, which should be paid attention to.

Many engineering disasters are related to water infiltration in cracks. Understanding the water infiltration in multi-layered sandstone cracks is crucial for monitoring and preventing water-related disasters in coal mines. In this study, we utilized the electrical resistivity tomography (ERT) technique to conduct a water infiltration monitoring experiment on the 2d-strata-model with cracks. The electrical resistivity ratio profiles with respect to the background unveiled the existence of three cracks. Model photography demonstrates two cracks of those cracks. The infiltration cracks exhibit distinct shape of a stripe or island chain electrical change ratio anomaly in the resistivity ratio profiles. Electrical resistivity change ratio is associated with the infiltration within the cracks. As the infiltration progresses, the resistivity change ratios relative to the background gradually decreases. This is evident in the reduction in ratios in the original stripe or island chain areas in the electrical resistivity ratio profiles. The diminished range expands, manifesting as an increase in the area of the original stripe or island chain. The infiltration patterns of the cracks can be categorized into three types: a stripe pattern, island chain and stripe pattern, and island chain pattern. The preferential flow paths along the crack are related to both the infiltration time and the volume of infiltration. In the early stages, there are clear preferential flow paths along cracks. However, as infiltration time and volume increase, these preferential flow paths along the cracks become less pronounced and may even disappear. The findings prove that ERT is suitable for monitoring water infiltration along the cracks in multi-layered sandstone in the early infiltration stage. Experiment results monitoring water infiltration cracks on the 2D-model show that the ERT and 2D-model are suitable for studying water infiltration along the cracks. This research can provide valuable reference for preventing engineering disaster.

The current ice lake dataset in the western region of Nyingchi requires further improvement. Due to the intricate distribution of ice lakes and imprecise boundary delineation, research tends to overlook small-scale ice lakes in this area. Moreover, most related studies have focused solely on variations in ice lake areas within key regions, such as the Himalayas, with little attention given to changes occurring in southeastern Tibet. The frequency of ice and snow disasters in the study area has been steadily increasing over the years. Therefore, this study utilizes Landsat satellite images and employs visual interpretation methods to generate more precise and comprehensive maps depicting the distribution of ice lakes in the western region of Nyingchi Province for the years 1994, 2010, 2018, and 2022. Additionally, changes in scale and spatial patterns of different types of ice lakes were investigated. Between 1994 and 2022, the ice lake area in the study area significantly increased by 22.5%, reaching a total of 35.8 ± 3.0 km 2 . This expansion was primarily driven by glacier-fed lakes, which experienced a remarkable growth rate of 30.8%. In contrast, the non-glacier-fed lakes experienced an increase by only 15.6%. Notably, ice lakes at higher elevations exhibited a peak in expansion, with those above 5143.0 m experiencing the most substantial growth rate of 44.8%. The long-term expansion rate of ice lakes is investigated through the measurement of changes in their boundaries, with the aim to understand the factors contributing to their growth. These findings indicate the rapid expansion of the ice lake near the glacier, with an annual growth rate of 1.3% per annum. Specifically, the glacial-fed section exhibited an expansion rate of 1.1% per annum, while the nonglacial-fed section experienced a growth rate of 0.6% per annum. The seasonal variability in marine glaciers is the primary factor influencing the expansion of ice lakes in this region, with temperature and precipitation serving as the principal driving forces impacting the transformation of these lakes. The data provided by the research results will facilitate a comprehensive understanding of the dynamics and mechanisms governing the ice lake in western Nyingchi, thereby contributing to an enhanced scientific comprehension of potential disaster risks associated with this ice lake.

Landslides often occur in the study area as a continuation of the erosion process on very thick soil from a series of volcanic ash deposition during the Tertiary and Quaternary periods. Rapid land cover changes from agricultural land into settlement increase runoff significantly causing accelerated soil erosion. Soil conservation approaches using parameters to reduce surface runoff and soil loss are less acceptable in agricultural society. Soil conservation methods aimed at reducing runoff and soil loss are not widely embraced in agricultural communities, efforts in soil conservation must be economically beneficial. Vegetative-based erosion control is the most suitable option for the agricultural communities. However, there needs to be improvements in terms of plant arrangement that is adapted to the spatial arrangement of slopes and is focused on zones along rills and gullies. Selection of tree species planted for erosion control that have the value of increasing economic income is the key to the success of planned soil and water conservation efforts.

The article establishes a depositional model for lacustrine hyperpycnal flow by examining dynamics, transport factors, and laminae formation. The results show that several typical experimental phenomena such as fluid front mixing, double flow division, underwater leap, water skiing, and “new head” can be observed in the flume experiment. Based on the experimental observation of the flow process, three modes of transport of hyperpycnal flow in freshwater lake basins are summarized: bottom-bed loading, suspended loading, and uplift loading. Further, the change of fluid properties in hyperpycnal flow is summarized in three stages: a high-concentration stage, a low-concentration stage, and an uplifting stage. There are two main factors affecting the long-range transport of hyperpycnal flow: (1) the concentration difference between the head deposits and the ambient water body and (2) shear force of turbulence in the upper part of hyperpycnal flow. The simulation experiments of hyperpycnites laminae show that the laminae change from continuous to intermittent with the increase of the transportation distance. It is clear that the mode of transport of the hyperpycnal flow has a controlling effect on the degree of development of the laminae. Eventually, a depositional model of lake-facies hyperpycnal flow under experimental conditions was constructed.

The injectability of mudstone is a key parameter for grout modification and is affected by hydration. Inherent injectability is predominantly determined by pore size distribution nuances, encompassing both the critical pore size and the heterogeneity inherent within the pore structure. In this study, low-field nuclear magnetic resonance technology is employed to delineate the transverse relaxation time distribution curves amidst the hydration process of three distinct clay rocks, namely kaolinite, illite, and montmorillonite. The evolution characteristics of permeability are assessed, leveraging the Schlumberger-Doll research model. It is ascertained that a prolonged hydration reaction (98 days) engenders a self-healing effect pertinent to rock permeability. A comprehensive analysis unveils the impacts rendered by various types of clay minerals and distinct durations of hydration upon the characteristic distribution of rock pore sizes. The diffusion and seepage pores are distinguished based on a pore diameter boundary of 100 nm, and the time-varying characteristics of their heterogeneity are studied based on fractal theory. The research results show that for rocks without clay minerals, the injectability reaches and basically maintains 11% unchanged after being soaked for 9 days. For rocks containing kaolinite, the injectability reaches and basically maintains 3.4% unchanged after being soaked for 42 days. For rocks containing illite, the injectability reaches a maximum of 0.9% after being soaked for 56 days, then slowly decreases to 0.6%. For rocks containing montmorillonite, the injectability reaches and remains unchanged at 7.8% after being soaked for 28 days. Combined with the time-varying characteristics of the fractal dimension of seepage pores, the heterogeneity of seepage pores weakens, so the pore structure evolution caused by the hydration of clay minerals has a beneficial effect on the injectability of muddy rock masses.

Buried objects with regular geometric shapes appear as hyperbolic structures in ground-penetrating radar (GPR) images. The shapes of these hyperbolic structures differ depending on the geometric shapes of the objects. In this study, current deep learning-based object detection algorithms such as Faster R-CNN, YOLOv5, and single-shot detector are used to detect hyperbolic structures in GPR images and classify the buried object according to its geometric shape. A mixed data set is produced for training the models. A GPR measurement device is designed with a vector network analyzer and Vivaldi antenna pair to be used in laboratory measurements. Objects with rectangular and cylindrical geometric shapes are placed under the table and measurements are performed. The measurement scenarios created in the laboratory are modeled in the gprMax program and synthetic GPR data are produced. Data augmentation techniques such as flipping and resizing are applied to expand the data set. As a result of the training, three models successfully detect the objects and classify them according to their geometric shapes. The Faster R-CNN model gives the most accurate detection and classification with the metrics classification loss = 5.4 × 10 −3 , localization loss = 9 × 10 −3 , regularization loss = 5.1 × 10 −5 , mAP@0.5 = 1, and mAP@0.5:0.95 = 1.

This study highlights the potential risks of pollution due to the presence of trace metals in sediment samples from six sediment cores from four wetlands (Chott Melghir, Fontaine des Gazelles dam, Lake Mellah, and Algiers Bay) in Algeria, assessing the level of contamination of these trace metals, and understanding the behavior of metals as a function of the depth of the sediment cores and the nature of the different sampling media. A total of 130 sediment samples were collected and subjected to chemical analysis (loss on ignition, inductively coupled plasma mass spectrometry, and atomic absorption spectroscopy to determine M.O. and trace metal contents) and physical analysis (X-ray fluorescence and DRX to identify the chemical composition and mineralogy of the sediments). Calculation of the enrichment factor enabled us to differentiate between anthropogenic and natural sources of trace metals such as Zn, Pb, Cr, Ag, and Cd, showing contamination at various sites due to urban or agricultural inputs. The dominant mineralogical composition of the sediments at the four sites was quartz, carbonate, and sandstone. Principal component analysis revealed strong positive correlations in the chemical composition of sediment samples between chlorine and Na 2 O, K 2 O, TiO 2 , Al 2 O 3 , and Fe 2 O, the main components of clays. The presence of organic matter in the four study areas is directly linked to the introduction of organic matter from the wadis into the watershed. Sediments have a high redox activity, which facilitates the movement of trace metals.

Normalized difference vegetation index (NDVI) and land surface temperature (LST) are important indicators of ecological changes, and their spatial and temporal variations and spatial coupling can provide a theoretical basis for the sustainable development of the ecological environment. Based on the MOD13A1 and MOD11A2 datasets, the spatial distribution characteristics of NDVI and LST from 2000 to 2020 were analyzed, and the trend change slope method and spatial coupling model were used to calculate the significant changes. Finally, the spatial coupling model was used to calculate the spatial coupling degree between NDVI and LST. The study shows that: (1) From 2000 to 2020, the annual NDVI value of the Mu Us Sandy Land was between 0.25 and 0.43, showing a stable upward trend overall, with an increase rate of 0.074/(10a). The proportion of improvement areas in the study area is 81.48%. (2) There are significant differences in the spatial distribution of surface temperature in Mu Us Sandy Land, showing an overall trend of decreasing from northwest to southeast and higher in the west than in the east. The LST of Mu Us Sandy Land is greatly affected by changes in land use types. The spatiotemporal variation trend of LST is different from the gradual warming trend of global climate change. The main reason is that human activities have changed land use types and increased local vegetation coverage. (3) There is a significant negative correlation between LST and NDVI in Mu Us Sandy Land, with an R 2 of 0.5073 and passing the significance test at the 0.01 level. This indicates that ecological engineering policies can effectively reduce LST in the study area, thereby achieving the effect of improving the environment. The overall spatial coupling between LST and NDVI is at a very high level, with an average coupling degree of 0.895 in the study area. The two mainly exhibit a state of mutual antagonism in space, reflecting the importance of green vegetation in regulating regional climate and LST. The vegetation index and spatiotemporal variation of LST in Mu Us Sandy Land are the result of the joint influence of human activities and climate change, and human activities dominated from 2000 to 2020.

Gravity flow sand body is an important reservoir for deep water deposition. The in-depth study of its formation mechanism and oil enrichment law can provide important guidance for oil and gas exploration in deep water areas. In this article, taking the deep-water gravity flow sand body of the Triassic Chang 6 3 sub-member in the Huaqing area as an example, the identification characteristics, formation mechanism, and oil-bearing characteristics of the gravity flow sand body are systematically discussed. The results show that sandy debris flow, turbidite flow, and mixed event flow present different superposition combination modes on vertical gravity flow deposition. The lithofacies of the gravity flow sandstone complex are mainly affected by lake level fluctuation, provenance supply, and hydrodynamic conditions. According to the formation conditions, sedimentary types. and distribution characteristics of deep water gravity flow sand bodies, a three-dimensional sedimentary mode of deep water gravity flow sand bodies is established. It is found that the physical and oil-bearing properties of the sandy debris flow sand body are better than those of the turbidity flow sand body. The reason is that the proportion of debris in the sand body of sandy debris flow is high, and the content of debris particles is generally greater than 70% according to the statistics of thin sections, which is conducive to the formation of pores. Second, sandy debris flow belongs to block transport, and the mixing of lithology is not sufficient in the process of block flow transport, so some pores will be preserved. Finally, gravity flows, which are dense at the beginning, become less dense later as detrital sediments unload, allowing them to be transported to distant regions. Therefore, the monolayer thickness of the sandy debris flow sand body is large (generally greater than 0.5 m), and the particle size of the debris ranges from 0.03 to 0.3 mm. Finally, the physical and oil-bearing properties of the sandy clastic flow sand body are better than those of the turbidity flow sand body.

Upper Permian Longtan Formation transitional shale has become an important exploration layer, but the Longtan Formation shale (LFS) has a complex mineralogical composition, which affects the subsequent diagenesis and diagenetic evolution, and restricts the subsequent geologic exploration of shale gas. In this article, the observation of drilling cores, argon ion polishing-scanning electron microscope, Vitrinite reflectance, and X-ray diffractometer were used to analyze the type and characteristics of diagenesis of the LFS and clarify the stage of diagenetic evolution. The results show that the main diagenesis in the LFS is compaction, cementation, thermal maturation of organic matter (OM), dissolution, and transform of clay minerals. Among them, OM hydrocarbon generation, clay mineral transformation, and dissolution are pore-enhancing diagenetic events. Compaction and cementation are pore-reducing diagenetic events. The transitional and marine shales have similar characteristics of diagenesis, but there are big variations in the diagenesis of OM hydrocarbon, authigenic quartz, and siderite. The complex depositional environments of the marine-continental transition environment have resulted in a variety of rock types, which in turn influenced the diagenesis types and diagenetic evolution process. Compared with the transitional shales of the Shanxi and Taiyuan formations in the South China North Basin, the LFS are characterized by high clay content, low quartz content, complex mineral compositions, and a higher degree of thermal evolution.

In this article, we collected the seismic phase arrival data (115°–120°E, 34°–39°N) of 2,833 local natural earthquakes above magnitude 1.0 recorded by 128 seismograph stations provided by the China Earthquake Networks Center covering the period from January 2008 to October 2023. We extracted the first arrival P- and S-wave arrival time data and obtained 26,351 P- and 26,349 S-wave absolute arrival times and 99,627 P-differential and 99,625 S-differential arrival times. Then, we determined 3-D P and S wave velocity structures under the Luxi region by using the double-difference tomography method. The results show lateral heterogeneities under the Luxi region, and the distribution of surface basins and uplift zones is associated with seismic velocities within the crust. The vertical section shows the widespread presence of vertical high-velocity bodies within the crust of the Luxi region, indicating seismological evidence of mantle upwelling in the region. Meanwhile, our imaging results also clearly indicate the presence of a significant low-velocity anomaly at depths of 13–17 km, which corresponds to the presence of a high-conductivity layer at that depth obtained from electromagnetic bathymetry. The transition zone between high and low velocities exists at a depth of 7–13 km, which plays an important role in the transfer of lithospheric stresses from the deep to the shallow part of the lithosphere. Combined with the results of the previous deep seismic wave velocity structure, petrology, and geological investigations, the deep dynamical background of the formation of slip tectonics and seismic mechanism in the Luxi area can be attributed to the go-slip activity of the Tan-Lu fault Zone, the subduction of the Pacific Plate, and the magmatism generated by mantle upwelling.

The evolution of metamorphic core complexes is closely related to gold formation. Due to the thick cover and orebodies’ lying depth, exploration regularities, and metallogenic prediction have faced challenges. Therefore, new data were obtained through controlled-source audio magnetotelluric (MT) and broadband MT methods to predict the ore-bearing properties at depth and decipher the spatial coupling relationship, respectively. The results of broadband MT surveys allow us to identify the thick cover (apparent resistivity of 3,000 Ω m), the strongly deformed metamorphic rock (apparent resistivity of 18,000 Ω m), and two low-angle detachment faults (apparent resistivity from 5,000 to 8,000 Ω m). The fault-dip value on the left side is roughly 30°, while on the other side, the values significantly change from 30° to 75°, although they are in the same structure. Moreover, the controllable source audio MT method provides more detailed examinations of the right side fault. The proved ore-bearing gold orebodies were all located in the transition zone where the inclination angle changes from steep to gentle or gentle to steep. The discovery of this mineralization pattern allows us to evaluate the mining prospecting potential and predict the deep-seated metallogenic location. Based on the geotectonic environment and the geophysical profiles, we conclude that the coeval exhumation of the metamorphic core complex with non-symmetrical northwest-southeast shear senses may have resulted from a decratonization event during the retreat of the Paleo-Pacific Plate.

This research meticulously explores the spatial variances in the allocation of public service facilities within Wenzhou’s central urban area, deploying a lens of “living circles” and utilizing a 15-min walkable distance as a pivotal metric. Employing a suite of analytical methods, including kernel density estimation, nearest neighbor index, Ripley’s K, and Z -score analysis, and leveraging Amap data, the study unveils pronounced disparities in both the quantity and distribution of public service facilities. Notably, a conspicuous concentration of facilities, particularly in transportation and commercial sectors, is observed in the early-developed core region, while surrounding areas manifest a palpable deficiency in both quantity and category, impacting residents’ quality of life and accessibility. The research further delineates a “single-center” structural pattern in the spatial distribution of public service facilities, albeit with distinct patterns for different facility types. Furthermore, a comprehensive evaluation at the street level, considering factors such as comprehensive accessibility scores, variation coefficients, and population density, reveals substantial disparities and internal variations in facility accessibility among different streets. The findings underscore a critical need for strategic optimization in the allocation of public service facilities, with recommendations including supplementing facilities based on extant needs, addressing internal disparities among streets, and prioritizing facility development in streets characterized by diverse attributes and population densities. This study not only augments our understanding of spatial disparities in public service facility distribution but also provides actionable insights for enhancing strategic allocation and planning in Wenzhou’s central urban area, thereby contributing to the burgeoning body of knowledge in urban planning and public service facility allocation within the context of living circles.

The value of war heritage is usually reflected in the historical process constituted by the correlation among many heritages rather than a single heritage itself. Traditional heritage protection strategies often focus on ontological protection of heritage, while the inherent relevance between heritage due to their joint participation in historical events is often ignored. Therefore, it is extremely necessary to connect the scattered heritage sites spatially through certain logic, to show the historical process as a whole, and to maximize the integration and protection of the entire resources of the heritage protection mode. Taking the war heritage of Jinzhai as the object, this article analyzes the overall distribution characteristics of the war heritage and the formation process of the war heritage field on the basis of the field theory, and then puts forward the spatial sorting steps based on historical events. The research shows that it is feasible to use key historical events to organize the space of many war heritages to obtain a kind of integrated structure, which can be used as the basic framework for the future use of heritage protection, tourism development, heritage display, and utilization.

Embarking on systematics, the formation mechanisms of Danxia landforms were explained from perspectives of human activities, geography, and climate. The formation mechanisms of Qiaoba-Zhongdu Danxia landforms in the research region were systematically discussed using theories and methods in sedimentology, paleo-climatology, tectono-dynamics, and surface process dynamics. Meanwhile, approaches such as remote-sensing imagery interpretation, rock and ore identification, geochemical analysis, and interpretation of seismic profiles were also adopted. Research results show that Qiaoba-Zhongdu Danxia landforms are in the mature stage of landform evolution. The formation process involves five stages including being bred by sedimentation, rendered by paleo-environmental conditions, landscaped by tectonism, carved by geomorphologic agents, and embellished by human activities.

The south-eastern part of the Egyptian desert had been waiting for a long time for an exploration process of hydrocarbon potentiality. In this research, we are addressing the available high resolution airborne magnetic data of Delta Wadi Diit area, which were processed and interpreted to map the basement depths and structures as an aid for hydrocarbon potentiality elucidation. Applying a set of automatic interpretation techniques to the magnetic data enabled mapping the tectonic framework of the study area and determining the depth to the basement (in other words, thickness of sedimentary section), which are vital factor of hydrocarbon field analysis. These techniques involve edge detection, depth estimation, as well as 2D and 3D modeling. Edge detection methods include the horizontal tilt angle (TDX) and improved logistic function of total horizontal gradient. Moreover, Euler deconvolution, tilt angle, and source parameter imaging provide both location and depth of the magnetic sources. Interpreted structures reveal that Wadi Diit area is highly affected by shallow and deep-seated faults trending in NW-SE and ENE-WSW and NNE-SSW directions. These fault systems control the surface water drainage network, the contacts of different rock types, the Red Sea rift boundary, and local and reginal basin areas. Depth estimation techniques reveal that the depth of the basement rocks ranges from 300 to 3,500 m for the inshore parts and from 2,500 to 5,000 m for the offshore parts of the area. Basement structure of the area was then refined through applying 2D modeling along two selected profiles and 3D modeling of RTP magnetic data for the entire area. The final depth map reveals major offshore basins at the northeastern side with sedimentary section of more than 3 km thickness. Moreover, local basins are delineated inshore at the southeastern parts. The eastern part of the study area can be considered to be having high hydrocarbon potentialities. Moreover, the inshore basin areas are suitable for groundwater accumulation that makes Wadi Diit delta as one of the most promising areas for sustainable development along the Red Sea’s shore.

To reveal the diagenetic sequence of reservoir rocks in the central part of the deep depression basin, the Wuerhe Formation in Junggar Basin was taken as an example to conduct the detailed studies on its sedimentary facies, diagenetic sequence, and the micropore structure evolution rules based on the comprehensive data from a super deep exploration well C-6 (approximately 7,000 m in depth). First, an arid environment fan delta sedimentary model of the Wuerhe Formation was established, and its sedimentary evolution law was clarified as a gradual transition from a fan delta front to a fan delta plain during the water-regression process until the lake dried up. Then, the diagenesis types and evolution sequence of the Wuerhe Formation, and the influence degrees of the compaction, cementation, and dissolution on the rock formation process were clarified. Finally, the diagenesis and pore evolution model was established, and the greatest impact factors of the late reservoir densification were clarified. Based on this research, the diagenesis and pore evolution processes of the deep rocks in the studied deep central sag were ultimately revealed to provide useful guidance for the deeply buried oil and gas reservoir exploration.

Earthquake-triggered landslides are one of the most significant hazards worldwide. These landslides, involving small or large volumes, can develop debris flows or avalanches with high mobility and long runout distances. The motion processes of this type of landslide are also quite complicated. This study reproduced the motion processes of two landslides using the LS-RAPID program. The Aso-Bridge landslide occurred on April 16, 2016, and it featured rapid movement and a long runout distance. The Kataragai landslide occurred on April 9, 2018, and it traveled with a flow-like behavior. This work presents the features and mechanical parameters of these two landslides by means of survey investigations and laboratory experiments. We established pre-failure models and reproduced motion processes of these two landslides using the LS-PAPID program. Two indicators, consisting of the sliding speed and traveling morphology at different intervals, were considered to describe the motion processes. Results indicated that the resultant maximum sliding speeds of these two landslides were approximately 297.1 and 43.6 m/s, respectively, and that post-failure morphologies were consistent with those observed in field investigations.

The Sunda–Banda arc transition zone features the collision of the Indo-Australian oceanic plate and the Australian continent, resulting in intricate geological and geodynamic conditions. Tectonic activity in this region is shaped by the convergence of multiple major plates, including the Indo-Australian oceanic plate and the Eurasian plate. The crustal structure along the Sunda–Banda arc transition zone is complex and influenced by various factors such as subduction, continental collision, and volcanic activity. The tectonic complexity of the region in eastern Indonesia makes it an interesting area for study. In this research, International Seismological Centre-Engdahl-van der Hilst-Buland catalogue data from 1964 to 2020 were used, which include recorded information on 69.705 earthquake events from 1.185 recording stations and consist of 2.943.974 P phases. Resolution testing was performed using various velocity grids, and optimal results were obtained with a medium resolution of ∼100 km × 100 km × 80 km for the inversion process. The tomographic inversion analysis provided valuable insights into subsurface structures within Earth’s crust and mantle up to a depth of approximately 750 km. The occurrence of deep earthquakes in the study area has provided valuable insights into complex dynamics associated with subduction and plate tectonics. The results of the tomographic inversion analysis reveal that earthquakes are concentrated in areas with high-velocity anomalies, indicating intense tectonic activity near the subduction zone. This study offers the perspective on the structural complexities and earthquake origins in the Sunda–Banda arc transition zone following the 2023 Mw 7.1 Bali Sea earthquake, which occurred on August 29, 2023, at 02:55:32 UTC + 7, approximately 163 km northeast of Lombok, Indonesia. This earthquake was caused by slab pull activity from the Australian Plate and involved a combination of downward and oblique-normal movement. These characteristics indicate the convergence and interaction between tectonic plates in the subduction process occurring in the Bali Sea area. As a result, there have been frequent occurrences of various tectonic and volcanic activities including earthquakes of different magnitudes. These results highlight the significance of the high-velocity anomaly connected to this occurrence, offering valuable insights into seismic behaviour and tectonic phenomena in the region. The findings of this study indicate that the deep earthquakes in the Bali Sea may be induced by faulting due to the transformation of metastable olivine into denser spinel at significant depths, along with shear instability caused by phase transitions within Earth’s mantle layers. This theory proposes that stress-induced changes in phase can initiate shear instabilities and subsequently lead to deep earthquakes.

Slope stability analysis is an important part of rockfill dam design, and the uncertainty of rock and soil physical and mechanical parameters has a significant impact on slope stability. In this article, based on physical and mechanical parameters c and φ , simplified Bishop’s method and mean clustering method are adopted to study the influence of parameter cohesion c and internal friction Angle φ on slope safety factor k of composite geomembrane rockfill dam, and the key and non-critical areas of the dam are preliminarily differentiated according to the different influences of the changes in different sections of the dam body on slope safety factor c and φ . The research results show that whether c and φ change ±5 and ±10% simultaneously with single parameter or double parameter, it shows that cohesion force c has little influence on slope stability, while internal friction Angle φ is the most sensitive factor in slope stability calculation, and its numerical accuracy has a great influence on the calculation result of safety factor. In addition, the influence of c and φ in key areas on the stability of the dam body is more significant. Therefore, in the construction of a composite geofilm rockfill dam, a relatively accurate φ value is required when selecting parameters, especially in key areas. This study not only has a certain guiding significance for the property requirements of the selected soil, engineering safety, and engineering optimization design, but also puts forward some new methods and ideas for optimizing the design scheme and improving the safety of the dam.

The Weining-Shuicheng Fault (WSF) is a northwest-southeast trending fault in the southwest of the South China Block (SCB), which is an important component of the Yadu-Ziyun Fault Zone. The study of its activity is of great significance for analyzing the boundary role of the Daliangshan secondary block on the SCB. This paper derived the following results through field investigations, high-precision remote sensing image interpretation, UAV photogrammetry, trenching technique, and AMS 14 C age. The WSF is northwest-trending with a sinistral strike-slip. It has a total displacement of about 2.5–3.2 km, which is equivalent to that of the southern section of the Daliangshan Fault. There are visible landforms such as fault scarps and fault valleys along the WSF, which control the development of the Caohai Basin. The gully near Weining Airport was caused by left lateral dislocations with a displacement of about 4 m. The Tashan trench revealed two branching faults, cutting the latest strata formed during about 13,000 BC. The Wangjiachong trench revealed five branching faults, cutting the latest strata formed during about 20,000 BC. The northern section of the WSF is flower-shaped tectonic features near the plane and activated in the Late Pleistocene.

Climate variations during the Holocene significantly impacted vegetation dynamics in the eastern Qinghai-Tibet Plateau (QTP). However, vegetation evolution in response to regional climatic trends and events during this interval remains controversial. Here, we present well-dated decadal-resolution loss on ignition (LOI) and grain size records from the Xing Co Lake on the eastern QTP. The records show an overall drying trend since 10 thousand years ago (ka), with multiple extreme precipitation events observed during 10 to 7 ka. An extreme drought event occurred at around 5.5 ka, after which the climate was drier and unstable with several drought events. In comparison with the hydroclimate, insolation, and El Niño Southern Oscillation records, our data show a close correspondence with the summer insolation differential between 30°N and 30°S and El Niño events on orbital-millennium timescales. This suggested that the increased rainfall during the early Holocene on the eastern QTP can be attributed to the high insolation differential between 30°N and 30°S and low El Niño events. Conversely, the drying trend in the late Holocene appears to correlate with a low insolation differential and high El Niño events. Whenever ice-rafted debris events occurred in the North Atlantic, there was a corresponding occurrence of drying events in the late Holocene in the Zoige Basin. This suggested that teleconnection between the precipitation on the eastern QTP and the North Atlantic climate exists in the Holocene. When compared to independent hydroclimatic and arboreal pollen (AP%) records on the eastern QTP, the evolutionary trends and events of AP% align closely with local hydroclimate changes. This suggested that arboreal coverage could rapidly respond to climate change during the Holocene, but further studies are needed.

Coastal zones have intense human activity and are ecologically fragile. Assessing ecological risks in coastal zones is crucial to promoting ecological safety and sustainable development for coastal cities. However, the relationship between ecological risk assessment and distance from the coastline is indeterminate in current research. To solve this problem, this study constructs the sea–land gradient and reconstructs the landscape pattern index and landscape ecological risk index (ERI) considering the sea–land gradient paradigm. This study aims to analyze the spatial–temporal variation characteristics and effects of the sea–land gradient on landscape pattern and ecological risk in Dalian City from 2000 to 2015. The results show the following: (1) between 2000 and 2015, a significant effect of coastline on the coastal landscape pattern in Dalian is reducing landscape fragmentation. The extent of this influence gradually diminished along the sea–land gradient. The landscape aggregation of urban building sites near the sea was relatively high and gradually increased over the years; (2) in Dalian, the landscape ERI has decreased near the sea and increased near the inland year by year; (3) the dominant pattern of landscape ecological risk was characterized by a transition from high to low levels within the [0, 2.5] km zone, while a transition from low to high levels predominated within the [2.5, Max] km zone; and (4) the northern region in Dalian primarily goes from high to low risk in the buffer zone near the landside, whereas the southern area has this changing pattern in the buffer zone near the seaside.

Based on the perspective of conflict of interest between low-carbon ecology and economic and social development, this study explores the change mechanism of land use cover change (LUCC) and carbon storage (CS) in the context of “Dual-Carbon” goal and territorial spatial ecological governance, which is of great significance to optimize the construction path of “Dual-Carbon” goal and formulate low-carbon, ecological, high-quality, and sustainable economic and social policies in the urban areas. An integrated framework based on the System Dynamics model, the Patch Generation Land Simulation model, and the Integrated Valuation of Ecosystem Services and Trade-offs model was constructed to dynamically simulate the LUCC demand and CS of Wenzhou under four scenarios in 2035, and to analyze the spatial evolution mechanisms of LUCC and CS. The main results of the study show that in the Natural Development Scenario (NDS) and High-speed Urbanization Scenario (HUS), the expansion mechanism is similar, and the area of woodland decreases greatly, which is mainly caused by the rapid expansion of construction land and cultivated land. Under Low-carbon and High-quality Development Scenario (LHDS) and Ecological Safety Governance Scenario (ESGS), woodland and grassland increased significantly, mainly because low-carbon and ecological governance policies strengthened ecological land protection and limited construction land control. By 2035, the prediction results show that LHDS has the highest CS (2.231 × 10 5  kt), followed by ESGS (2.226 × 10 5  kt), NDS (2.191 × 10 5  kt), and HUS (2.142 × 10 5  kt). The range of increase and decrease was 0.189, −0.149, −1.676, −3.692%, and only in LHDS, CS increased by 42.05 kt. Therefore, in order to achieve the “Dual-Carbon” goal, Wenzhou needs to prioritize the combination of LHDS and ESGS to formulate relevant policies.

The characterization of reservoir fluid properties is a crucial component of oilfield operations, as it provides a vital data foundation for the development and optimization of oilfield work programs. However, the complexity of water-flooded, along with the mixed data from drilling and cable logging, and the inherently weak foundational research, make the evaluation of water-flooded formations difficult. Therefore, this article aims to address this challenge by proposing a new reservoir fluid identification method. In this article, an improved Markov variation field model is applied to map geophysical logging data and is integrated with a quantum hybrid neural network (HQNN) to address the nonlinear correlations between logging data. By integrating the non-standard Markov variation field with HQNN, this article constructs a novel reservoir fluid identification model. Experimental results demonstrate that the model achieves a recognition accuracy of 90.85% when trained on feature images mapped from logging data. Furthermore, the superiority of the HQNN was validated through eight sets of comparative experiments. Additionally, the model was further validated using logging data from blind wells within the block, demonstrating high predictive accuracy and proving its effectiveness for reservoir fluid identification in the PL block. The method proposed in this article not only addresses the challenge of evaluating water-flooded layers in the absence of key logging curves but also offers a novel approach to reservoir fluid identification using geophysical logging data. The non-standard Markov transition field model is employed to map logging data into feature images, offering a new perspective on the application of geophysical logging data in practical reservoir analysis.

In this research, we compared thermochronological and traditional one-dimensional thermal models across the Middle Magdalena Valley (MMV), Eastern Cordillera, and Eastern Llanos Basins in Colombia. These models allow us to relate cooling/heating histories to exhumation events, subsidence, fault activities, and fluid flow. The Eastern Cordillera and Eastern Llanos Basins are discriminated as prospective zones for hydrocarbon (HC) generation. The De Armas Syncline at the MMV basin shows high thermal maturity (127°C), describing rocks completely depleted in terms of HC generation. The eastern zone of this syncline is buried until it reaches temperatures above 150°C. The contrast between thermal models in the Eastern Cordillera basin suggests a possible sediment supply scenario from the west to the east of the Soapaga Fault. In the Eastern Llanos basin, the thermal histories between both models explain the latest uplift and sediment supply processes from the hinterland zone of the Eastern Cordillera to the foothill zone of the Eastern Llanos basin. In terms of thermal evolution, the three basins are different, reaching different levels of burial and HC maturity. However, in terms of cooling events related to exhumation, the basins have similarities as they are controlled by the mountain building of the Eastern Cordillera of Colombia.

This study aims to comprehensively characterize coal extracted from three active mines in northeastern Kazakhstan: Lenin, Saradyr, and Bogatyr. These mines exploit two Carboniferous coal-bearing formations, Dolyn and Karagandy. Dolyn, extracted by the Lenin underground mine at a depth of 700 m, contrasts with Karagandy, extracted at depths up to 260 m in Saradyr and Bogatyr. Six selected samples from the Lenin, Saradyr, and Bogatyr mines underwent various analyses, including proximate and ultimate analyses, elemental analyses (acid digestions with HCl + HNO 3 + HF, ICP-MS), and determination of mineral matter contents (XRD and SEM-EDS). This research aimed to understand the mode of occurrence of minerals and elements, technological and environmental implications of the coal seams extracted from these mines. Results indicate low sulfur and high ash content in the organic matter of all samples. Quartz and kaolinite dominate, with minor euhedral pyrite present in all samples. Framboidal pyrite, iron oxides, and rare earth element (REE)-bearing minerals are exclusively found in Saradyr and Bogatyr samples. Quartz and kaolinite likely reached the peat swamp through detrital processes, while pyrite formation occurred through both syngenetic and epigenetic processes in the coal samples. Ratios like Ce n /Ce n , Eu n /Eu n , Y n /Ho n , and Gd n /Gd n suggest REE deposition in anoxic hydrothermal water environments, possibly indicating a tuffaceous origin for the coal samples. Examining the elements’ mode of occurrence suggests their preferential association with mineral matter. Strong positive correlations among elements like Al, K, Na, Ti, Ba, Be, Ni, Cr, Co, Ga, Sc, V, As, Pb, Cu, Zn, and Zr, along with Eu and Sc of the REEs, suggest association with ash yield, consistent with kaolinite and accessory minerals. Comparative analysis of inorganic geochemical composition of coal worldwide reveals notable depletion of major, trace elements, and REEs in samples from all three mines, suggesting limited economic interest. Furthermore, coal samples containing trace elements pose minimal environmental impact.

The Jurassic Shaximiao Formation in the Sichuan Basin represents a significant tight gas reservoir, exhibiting marked permeability variations between the southern and northern regions of western Sichuan. This study examines the reservoir characteristics of the Shaximiao Formation, with a focus on the evolution of sandstone porosity under bidirectional provenance conditions and the underlying causes of permeability variations. The insights derived from this research are critical for the effective exploration and development of tight sandstone gas reservoirs. Analysis of core samples and thin sections through X-ray diffraction, cathodoluminescence, scanning electron microscopy, and electron probe microanalysis reveals that the southern region predominantly consists of feldspathic and lithic sandstone, whereas the northern region is characterized by feldspathic lithic and lithic feldspathic sandstone. The average porosity and permeability in the southern region are 10.52% and 0.1334 × 10 −3 μm 2 , respectively, while in the northern region, they are 9.74% and 0.5262 × 10 −3 μm 2 . The primary reservoir spaces are intergranular primary pores and intragranular secondary dissolution pores. Compaction significantly reduces porosity, particularly in the northern region (23.94%) compared to the southern region (22.75%), primarily due to the presence of chlorite coatings. Cementation further reduces porosity, whereas dissolution processes enhance it, elucidating the similar porosity values but differing permeabilities between the regions.

This study focuses on slope stability analysis, a critical process for understanding the conditions, durability, mass properties, and failure mechanisms of slopes. The research specifically addresses rotational-type failure, the primary instability mechanism affecting earth slopes. Identifying and understanding key factors such as slope height, slope angle, density, cohesion, friction, water pore pressure, and tensile cracks are essential for effective stabilization strategies. The objective of this study is to develop accurate predictive models for slope stability analysis using advanced intelligent techniques, including data mining mapping and complex decision tree regression (DTR). The models were validated using performance metrics such as mean absolute error (MAE), mean squared error (MSE), root mean square error (RMSE), and the coefficient of determination ( R ²). Additionally, overall accuracy was assessed using a confusion matrix. The predictive model was tested on a dataset of 120 slope cases, achieving an accuracy of approximately 91.07% with DTR. The error rates for the training set were MAE = 0.1242, MSE = 0.1722, and RMSE = 0.1098, demonstrating the model’s capability to effectively analyze and predict slope stability in earth slopes and embankments. The study concludes that these intelligent techniques offer a reliable approach for stability analysis, contributing to safer and more efficient slope management.

The Late Cretaceous granitic rocks are widely distributed in South China; however, the precise geodynamic mechanism remains controversial. To solve this question, we conducted whole-rock geochemistry, mineral chemistry, zircon U–Pb ages, and Lu–Hf isotopic data analyses of the Maqigang beschtauite, which is exposed in southeastern Guangxi. Laser ablation-inductively coupled plasma-mass spectrometry zircon U–Pb dating revealed the beschtauite emplacement at 83–85 Ma, representing Late Cretaceous magmatic activity. The rocks belong to the high-K calc-alkaline to shoshonite series and displayed metaluminous to weakly peraluminous affinity, with an A/CNK ratio ranging from 0.89 to 1.02. Whole-rock geochemical analyses showed that all rocks were enriched in Rb, Th, U, and K but depleted in Nb, Ta, Ti, Ba, and Sr. They were also rich in light rare earth elements with weakly negative Eu anomalies (Eu/Eu* = 0.61–0.77). The beschtauite showed typical A-type granitoid affinities, with rich silica (mean: 64.95 wt%), alkali (Na 2 O + K 2 O, mean: 7.55 wt%), and high field strength elements (Zr + Nb + Ce + Y = 427.40–599.60 ppm) contents, high FeO T /MgO (mean: 3.27) and 10 4 Ga/Al (mean: 2.75) ratios, and low Ba, Sr, Ti, and Eu contents. Mineral chemical analysis demonstrated that phenocrytic plagioclase was mainly andesite with an oscillating zone. Zircon Hf isotopic results showed zircon ε Hf ( t ) values ranging from −10.8 to −0.9 and T DM2 model age range from 1.2 to 1.8 Ga. These results indicate that the beschtauite was generated by the partial melting of ancient crustal materials via the underplating of mantle-derived magma. Based on these regional geological data, the Maqigang pluton was formed in an extensional back-arc setting associated with the continued rollback and retreat of the Paleo-Pacific plate subduction zone.

The porosity of the reef–shoal complex increases with the increase of dolomite content, and it is worth investigating whether dolomitization leads to the formation of new pores or maintains the original porosity. The reef–shoal complex of the Permian Changxing Formation in the Sichuan Basin is selected to reveal the modification effect of dolomitization on the reef–shoal complex. As important reservoirs of hydrocarbons and carbon dioxide, reef–shoal complexes are composed of grainstone and framestone on both sides of the Kaijiang-Liangping Trough during the Late Permian. The difference in the development degree of sparry calcite cement determines whether the framestone on both sides of the Trough undergoes dolomitization or not. When the Mg 2+ supply is insufficient, the dolomitization fluid prioritizes the replacement of the lime mud matrix. When the Mg 2+ supply is sufficient, the reef-building organisms and bioclastic grains are completely replaced by dolomite. Statistical results show that when the dolomite content increases from 0 to 40%, there is no significant change in porosity. When dolomite content increases from 40 to 60%, the porosity gradually increases slightly. When dolomite content exceeds 60% and continues to increase, the porosity increases sharply. For reef–shoal complex reservoirs, dolomitization did not lead to the formation of new pores, but effectively preserved primary intergranular pores and freshwater leaching-induced pores. The porosity increases with the increase of dolomite content, partly due to pore preservation and partly due to the more effective anticompaction (and pressure solution) effect of dolomite compared to calcite, reflecting the overall effect of dolomite pore preservation. Although early freshwater leaching played a positive role in the formation of dolomite reservoirs, the preservation effect of dolomite pores contributes more to the current porosity and permeability of reservoirs, resulting in the highest quality reservoirs of reef–shoal complexes often developing at a certain distance below the exposed surface, and the best reservoir is dolomite in the upper part of the reef–shoal complexes, rather than dolomite interval located at the top.

Geological characteristics, genetic model, and exploration implications in the Daduhe gold belt are studied. Three categories of gold deposits have been distinguished: “gold deposits in the basement (GDB),” “gold deposits in the cover layer (GDC),” and “gold deposits at the interface (GDI).” Among them, quartz vein type and quartz vein altered rock type are the main types of mineral deposits. The following features have been obtained: (1) inclusions of gold particles exist in pyrite, pyrrhotite, quartz, sellaite, and other sulfides; in fractures; or along cracks and grain margins. (2) The distribution curve of rare earth elements in pyrite and quartz indicates strong mineralization intensity in the GDB, (La/Sm) N fractionation characteristics, suggesting that pyrite may be more influenced by crustal materials and quartz by mantle materials. (3) The H–O and He–Ar isotopes manifested the ore-forming fluids derived from the mixing between crust and mantle. (4) The ranges of δ 34 S values of pyrite (−5.0 to 7.6‰) are consistent with those of metasomatized mantle lithosphere. (5) The homogenization temperatures and salinity of all quartz inclusions are concentrated from 150 to 210°C and 2.1–8.7 wt%, indicating a medium-low-temperature, low-salinity hydrothermal fluid. (6) The Daduhe orogenic gold deposits can be defined as epizonal subtypes. (7) The Daduhe gold deposits are medium-low temperature, low-salinity, and epizonal orogenic gold deposits, and fluid comes from a mixture of crust and mantle. In the future, efforts should be made to increase the exploration of deep gold deposits.

The deep coal-bed methane (CBM) resources represented by the Benxi Formation in the Eastern Ordos Basin have enormous potential and have achieved industrial breakthroughs in recent years. Rock physics modeling is a key research topic for predicting deep CBM reservoirs, but the relationship between parameters such as vitrinite reflectance (Ro), coal rock composition, total gas content, ash content, porosity, and elastic parameters is not clear, necessitating further research on rock physics models suitable for deep CBM reservoirs. On the basis of optimizing the skeleton parameters of the coal matrix (ash content, coal rock type), the porosity parameters of CBM reservoirs are obtained by using the nuclear magnetic resonance method. Equivalent calculation of adsorbed gas and total gas content using adsorbed gas as part of the coal matrix. Based on the measured data, calculate the pore fluid, temperature, and pressure data by taking the average or predicting the curve. Considering the geological characteristics and relevant background of deep CBM reservoirs in the Eastern Ordos Basin, a seismic rock physics model of hydrocarbon reservoirs considering the influence of CBM reservoirs was constructed. The specific process involves using coal matrix + adsorbed gas + matrix pores + cleat (or crack) pores as the dry skeleton, filling with water + free gas as the fluid, and using anisotropic rock physics modeling ideas to complete saturated coal rock physics modeling. By comparing the predicted longitudinal and transverse wave curves with actual measurements, the trends of the two are basically consistent, with a relative error of less than 1%, indicating that the model parameters are reasonably selected.

Enhancement methods of aeromagnetic data are widely used in mapping geological features. Many methods based on field gradients have been introduced to outline the source edges. However, the disadvantage of these methods is that they require the reduction to pole (RTP) or gradients of the magnetic potential directly measured by specific sensors. This study introduces a new method to enhance magnetic anomaly data without needing the RTP. This method uses the normalized source strength (NSS) calculated from the total-field magnetic anomaly, subsequently balanced by the tilt angle filter. The new method is tested on synthetic datasets and a real dataset of the Olympic Peninsula. The findings show that the presented method is less sensitive to variations in the source depth. These findings also showed that this method is less dependent on the magnetization direction and produces more precise and sharper boundaries than other methods. Thus, the presented method appears promising in providing a valuable tool for interpreting magnetic data compared to traditional methods.

Geotechnical site characterization is very important for construction purposes. This study has been conducted in Diriyah area northwest of Riyadh City, Saudi Arabia, using the Multichannel Analysis of Surface Waves (MASW) method for site characterization through shear wave velocity profiling to 30 m depth. Nineteen MASW lines were carried out in various directions and lengths through the area. The entire process was meticulously parameterized to extract shear wave velocity for subsurface characteristics. MASW results revealed four distinct velocity zones based on National Earthquake Hazard Reduction Program. Fill material was approximately half a meter thick and was classified as very dense soil. The second layer exhibited velocities ranging from 800 to 1,500 m/s, indicating weathered and highly fractured limestone. The third layer showed velocities varying from 1,500 to 1,800 m/s, representing slightly weathered limestone. The fourth layer displayed high velocities ranging from 1,800 to 3,600 m/s, indicating hard and compact limestone rocks. Geotechnical boreholes were drilled down to depths of 10–35 m. These boreholes exposed the geological model that consisted of fill material (silty sand with gravel), followed by highly to moderately weathered limestone with vugs and cracks, and finally, massive limestone rock. Analysis of shear wave velocities identified weak zones, particularly fractured and weathered limestone rocks extending to 12 m in depth. Sinkholes of circular, elongated, and/or conical shapes were observed within this depth range. Moreover, some sinkholes were detected at depths greater than 12 m in specific locations (sites 1, 6, 9, 11, and 17). These sinkholes agreed with the previous study. These results highlight the need for targeted ground improvement methods, such as grouting or underpinning, particularly for construction over weaker zones. Accurate site classification and effective risk management are crucial for addressing these geotechnical and seismic challenges.

Coal facies is an important indicator reflecting depositional environment of coal, which affects pore distribution. The effect of coal facies on the nanopore structure is essential for deep coalbed methane drainage. In this study, 13 coal samples from the Upper Triassic Talichik Formation in the Kubei-Bashi tectonic belt were collected. The coal facies type is determined based on the coal phase parameters (TPI–GI diagram). On this basis, nanopore diameter distribution is determined by using liquid nitrogen adsorption and CO 2 adsorption experiments. Then, single and multi-fractal dimensions are studied by using fractal theories. The results are as follows. The coal facies are classified into three types, namely low swampy reed phases (Type A, GI > 5, TPI < 1), wetland herbaceous swamp phases (Type B, GI < 5, TPI < 1), and dry forest swamp phases (Type C, GI < 1, TPI > 1). The pore volume percentage of micropores is similar amongst the three facies types, showing that the coal facies has little effect on the pore structure of micropores. The pore volume and specific surface area of meso-pores are the largest for coal facies A , indicating the most developed meso-pores in coal facies A . However, the pore volume percentage with a diameter of 2–10 nm in coal facies A is the lowest among the three coal facies. Above all, the coal reservoir under the wet overlying water depositional environment of coal facies A offers a relatively large pore volume as well as a specific surface area, which is more favorable for the exploration and development of coalbed methane; therefore, it is the advantageous coal reservoir in the study area.

Soil organic matter content (SOMC) is a key factor in improving the soil fertility of arable land. Determining how to quickly and accurately grasp SOMC on a regional scale has become an important task for farmland quality monitoring. Hyperspectral imaging remote sensing technology can enable large-scale SOMC estimation, owing to its large-scale and fine spectral resolution. Enhancing the accuracy and reliability of SOM estimation models based on hyperspectral satellite remote sensing has emerged as a prominent topic of study. In this study, feature spectral indices such as difference indices (DI), ratio indices, and normalized indices were extracted using the correlation coefficient method and used as variables to construct a regression model for SOM, with a split-sample regression method employed to account for the complexity of soil types and map the corresponding spatial distribution of SOM. The results showed that the SOM estimation model, built using these feature spectral indices from hyperspectral satellite imagery, achieved high predictive accuracy, with R ² values approaching 0.80 for most soil types. This demonstrates that the model effectively captures variations in SOM content across diverse soil backgrounds, highlighting its robustness and adaptability. The DI 499/576 combinations, in particular, contributed significantly to prediction accuracy, demonstrating their importance as key spectral parameters for SOM estimation. Furthermore, among the three sets of feature model variables derived from the split-sample regression strategy, the enhanced vegetation indices and Soil-Adjusted Total Vegetation Index exhibited distinct contributions to different soil sample groups. This variation reveals the specific responsiveness of these indices to soil properties, which further enhances model performance in varied soil contexts. This study provides innovative methods for large-scale SOMC estimation, particularly by utilizing hyperspectral indices to enhance model accuracy across various soil types, demonstrating substantial practical significance.

This study evaluates the impact of seepage on the integrity of artificial levees in low-lying regions, with a particular focus on Hungary, where levees built over a century ago lack comprehensive construction documentation, complicating current assessments of their effectiveness. Advanced geophysical methods – electrical resistivity tomography (ERT) and ground-penetrating radar (GPR) – were applied in a controlled tank experiment designed to simulate varied flood conditions along a 37-m levee section. The three-dimensional (3D) ERT profiles successfully delineated seepage pathways as the tank filled, while the 3D GPR profiles indicated areas of increased amplitude, corresponding to seepage zones and the water table. Validation through drilling confirmed the geophysical findings, underscoring the accuracy of ERT and GPR in non-destructively identifying subsurface features and seepage channels. The results highlight the applicability of these methods for evaluating levee integrity and seepage dynamics, offering a reliable approach for flood risk assessment in Hungary and similar flood-prone areas worldwide.

The SX area of the Ordos Basin in China is characterized by small thickness and considerable lateral variation of the reservoir, and high heterogeneity. It is difficult to identify gas and water by conventional P-wave seismic data without fully utilizing reservoir P-wave and S-wave information. Therefore, this study forms a series of seismic fluid detection technologies based on multi-wave seismic data, including the multi-wave “bright spot” feature analysis, multi-wave amplitude ratio technique, multi-wave amplitude versus offset analysis, multi-wave matched compression correlation analysis, and multi-wave pre-stack simultaneous inversion. The combined application of P- and S-waves facilitates visualized identification of fluids and improves the success rate of seismic prediction of underground gas-bearing features. The multi-wave interpretation technology series for low-permeability lithological gas reservoirs formed in this area has achieved a transformation from qualitative interpretation to quantitative prediction, and from lithological identification to fluid detection. These technologies have achieved significant geological results in the SX area.

A high geo-stress environment severely damages tunnel structures owing to the large deformation of the surrounding rock, thereby threatening their safety. In this study, the Wushaoling highway tunnel group, which passes through a high geo-stress environment, is investigated as a case study. The spatial distribution of different types of tunnel cracks is analyzed based on the site observations. The lining crack variations, such as circumferential and longitudinal cracks, with the factors including grade of the surrounding rock, location of buried depth, and design type of the tunnel lining are investigated. Various structural reinforcement technologies are presented based on the damage degrees of the tunnel linings. Several finite element models of supporting structures are established to reveal the mechanism of tunnel crack control technology. The results show that longitudinal and circumferential cracks are the main characteristics of tunnel lining damage in high geo-stress environments, accounting for approximately 29.4 and 53.2% of the total cracks, respectively. SIVb-, SVc-, and SVd-type linings show numerous longitudinal cracks per kilometer. The longitudinal cracks appear primarily on the tunnel crown and hance. In terms of the lining support types in Grade V surrounding rocks, the number of longitudinal cracks per kilometer increases with the lining grade. The number of tunnel cracks per kilometer tends to increase with the buried depth. Four tunnel structure reinforcement treatment measurements for lining cracks in high geo-stress condition were innovatively proposed, which were proved effective in deformation controlling and strengthening the tunnel lining using numerical investigation. The key contribution of this research is to reveal the characteristics and evolution mechanism of tunnel lining cracks in high geo-stress condition, and provide effective treatments for the tunnel lining cracks. In addition, the findings from the study on the tunnel lining cracks also provide industry practitioners with a comprehensive guide regarding the characteristics and control techniques of the tunnel lining cracks, which can serve as a steppingstone to facilitate the construction technology development of the transportation industry.

This study aims to characterize the pore structures and controlling factors of the Shan-1 Member reservoir in the southwestern Ordos Basin, a geological formation known for its significant gas production. Thin section analysis, scanning electron microscopy, high-pressure mercury intrusion (MICP), and reservoir physical property analysis were employed to investigate the pore structures within the reservoir. The Shan-1 Member reservoir is primarily characterized by lithic dissolution and intergranular pores, with generally small throat radii. Reservoirs with high quartz content (>70%) are associated with the development and preservation of primary pores, resulting in superior pore structures (Types I and II) with larger pore throats. Similarly, reservoirs with low lithic content (<10%) exhibit Type I and II pore structures, also with larger median pore throat radii. In contrast, Type III and IV pore structures, characterized by smaller median pore throat radii, are linked to higher lithic content. Compaction significantly degrades pore structures, while cementation and dissolution play key roles in controlling their variability. These processes underscore the complexity of the Shan-1 reservoir, with important implications for optimizing exploration strategies. This study provides novel insights into the interplay between mineral composition and diagenetic processes in shaping pore structures, offering valuable guidance for the exploration of tight gas reservoirs within the Permian strata of the southwestern Ordos Basin.

The Daniudi gas field in the Ordos Basin is a significant area for developing tight sandstone gas reservoirs in China. This study focuses on the Permian Shanxi and Lower Shihezi formations in the Da 17 well area, analyzing sedimentary model through petrological characteristics, physical properties, pore characteristics, and lithofacies characteristics. Findings reveal that the Shanxi Formation belongs to the deltaic plain sedimentary environment, which is divided into distributary channel and inter-channel, and identifies the microfacies of the main distributary channel and the sub-distributary channel. The Lower Shihezi Formation exhibits braided channel sediments, dividing them into channel bar sediments and flood plain sediments, and identifying isolated channel microfacies and superimposed channel microfacies. Analysis shows that sedimentation has an impact on reservoir properties through particle size, lithological characteristics, and sedimentary microfacies. The main distributary channel and superimposed sandbars are favorable microfacies for the formation of gas reservoirs. The porosity of the main diversion channel ranges from 8 to 13%, and the permeability ranges from 0.3 to 0.6 × 10 −3  m 2 . The porosity of the superimposed sandbar ranges from 8 to 15%, with a permeability of 0.3–2.2 × 10 −3  m 2 . This study provides a theoretical foundation advancing tight sandstone gas development in the Daniudi gas field.

Territorial spatial resource changes play an irreplaceable role in the human development process, providing the necessary dependency conditions and ecosystem services for human production and life. This article takes Jilin Province, China, as the study area, analyzes the characteristics of the dynamic evolution of territorial spatial in Jilin Province from 1985 to 2020, and simulates the spatial and temporal changes of land space in Jilin Province under three different scenarios in 2030. The results show that: (1) From 1985 to 2020, the productive space (PS) and living space (LS) show a gradual increase trend; the ecological space (ES) shows a decrease trend. The LS is scattered except in the Changbai Mountain area; the PS is mainly concentrated in the west and expands year by year; the ES is mainly in the east, and its scope shrinks year by year. (2) From 1985 to 2020, the center of gravity of PS changes more slowly and moves northward as a whole. The change of the center of gravity of LS is mainly concentrated in Changchun, and its center of gravity is shifting southward. The center of gravity of ES moves more sharply, first to the northwest and then gradually to the southeast. (3) Under the natural development scenario in 2030, the territorial spatial area fluctuation is mainly in the north of Songyuan City, central Jilin City, and the north of Changchun City. Under the ecological protection scenario, the area dynamics of Changchun City, Songyuan City, and the northwestern part of Baicheng City change significantly. Under the economic development scenario, the hotspot areas of spatial area change are mainly in the western part of Jilin Province.

Biofouling constitutes one of the main obstacles in the sector of shellfish farming. Under this perspective, it is of highly importance to critically combine the updated information regarding the invasive potential of ascidian species, together with the factors contributing toward these events. The biological features of each species in relation to the gathering of the main non-indigenous species in the Mediterranean basin represent the first step toward mitigation of negative effects of the phenomenon. Further, there are limited studies investigating the physiological changes of bivalves caused by biofouling while leading to an increase in stress biomarkers. In the present review, the major ascidian species negatively affecting bivalve culture in the Mediterranean Sea are presented, alongside monitoring of ascidians from four Greek mussel farming locations as typical mussel culture cases. Among the main ascidian species, Styela plicata , Clavelina oblonga , Ciona robusta , Aplidium sp., Didemnum sp., Botryllus schlosse r i , and Didemnum drachi are included, with the last three being the most harmful for this aquaculture sector. Based on the existing literature and research conducted so far, future research directions are proposed, in an effort to effectively control or efficiently manage ascidian biofouling organisms. Overall, perspectives toward the way we manage the biofouling phenomenon, such as the use of ascidian’s by-products in feedstuffs, chemical and pharmaceutical industry, or their incorporation in bivalve co-culture and integrated multi-trophic aquaculture systems represent promising alternative approaches.

Drought prediction is crucial for mitigating risks and designing measures to alleviate its impact. Machine learning models have been widely applied in the field of drought prediction in recent years. This study concentrated on predicting meteorological droughts in southwest China, a region prone to frequent and severe droughts, particularly in areas with sparse meteorological station coverage. The long short-term memory (LSTM) predictive model, which is a deep learning model, was constructed by calculating standardized precipitation evapotranspiration index (SPEI) values based on 144 weather station observations from 1980 to 2020. The 5-fold cross-validation method was used for the hyperparameter optimization of the model. The LSTM model underwent comprehensive assessment and validation through multiple methods. This included the use of several accuracy assessment indicators and a comparison of results. The comparison covered different drought characteristics among the LSTM predictive model, the benchmark random forest (RF) predictive model, the historical drought situations, and the calculated SPEI values based on observations from 144 weather stations. The results showed that the training results of the LSTM predictive model basically agreed with the SPEI values calculated from weather station observations. The model-predicted variation trend of SPEI values for 2020 was similar to the variation in SPEI values calculated based on weather station observations. On the test set, the coefficient of determination ( R 2 ), the root mean square error, the explained variance score, the Nash–Sutcliffe efficiency, and the Kling–Gupta efficiency were 0.757, 0.210, 0.802, 0.761, and 0.212, respectively. The total consistency rate of the drought grade was 59.26%. The spatial correlation distribution of SPEI values between LSTM model prediction and calculation from meteorological stations in 2020 was more than 0.5 for most regions. The correlation coefficients exceeded 0.6 in western Tibet and Chengdu Plains. Compared to the RF model, the LSTM model excelled in all five performance evaluation metrics and demonstrated a higher overall consistency rate for drought categories. The Kruskal–Wallis test for both the LSTM and RF models all indicated no significant difference in the distributions between the predicted and observed data. Scatter plots revealed that the prediction accuracy for both models in 2020 was suboptimal, with the SPEI showing a comparatively narrow range of values. Nonetheless, the LSTM model significantly outperformed the RF model in terms of prediction accuracy. In summary, the LSTM model demonstrated good overall performance, accuracy, and applicability. It has the potential to enhance dynamic drought prediction in regions with complex terrain, diverse climatic factors, and sparse weather station networks.

Can large language models (LLMs) capture a trustworthy global snapshot of the current issues and top-priority questions facing Earth and Geoscience? This article discusses the 100 most important questions facing Earth and Geosciences in the twenty-first century according to the largest of the LLMs. The study uncovered a discrepancy in responses using the synonymous terms earth sciences and geosciences ; as such, users of publicly accessible LLMs must account for this bias and exercise caution in interpretation. Eight fundamental topics irrespective of the query terms earth sciences/geosciences were found: while two of them originate from fundamental research in extraterrestrial geoscience and Earth’s interior, the remaining six address geoscientific questions, important due to the associated societal challenges and environmental issues. The outlined eight fundamental topics strongly resonate with eight Sustainable Development Goals of the United Nations, in certain cases with not just one. Graphical abstract

The objective of this study is to analyse the spatial-temporal patterns of traffic accidents using data from 2011 to 2020 for the AP Vojvodina. The spatial-temporal patterns of traffic accident hotspots were identified at the municipality level using the Getis–Ord G i ⁎ {G}_{i}^{\ast } statistic in ArcGIS Pro software. Trends in traffic accidents were analysed using the Mann-Kendall (MK) statistic. A certain trend in the number of traffic accidents, fatalities, and injuries was detected in 15 out of 45 municipalities. In two municipalities, the trend in the number of traffic accidents is decreasing, while in seven, it is increasing. In three municipalities, a decreasing trend in the number of traffic fatalities was observed. A decreasing trend in traffic injuries was identified in five municipalities. Hotspot analysis on the number of traffic accidents and traffic injuries revealed hotspots in seven municipalities, while no hotspots were detected in the number of traffic fatalities. In the traffic casualties weighted number, persons in tractors, hotspots were identified in two municipalities. This research has the potential to enhance traffic safety by directing targeted safety measures towards identified hotspots. Such measures could ultimately lead to a reduction in traffic accidents, consequently curbing the number of both fatalities and injuries.

This comparative study aims to investigate environmental awareness, knowledge, and safety among students in Montenegro and North Macedonia, considering the unique socio-cultural and environmental contexts of both countries. A mixed-methods approach involving surveys and interviews was employed to gather data from students in educational institutions across Montenegro and North Macedonia. The study assessed various factors, including students’ awareness of environmental issues, their perceived level of knowledge, and their attitudes towards safety measures. A comprehensive series of 400 face-to-face interviews was carried out, and these interviews encompassed 200 students from Montenegro and an equal number from North Macedonia, taking place at two esteemed academic institutions: The University of Montenegro in Podgorica and The University of St. Clement of Ohrid, Bitola, Republic of North Macedonia. Our hypothetical conceptual framework proposes that a combination of variables, including gender (H1), age (H2), year of study (H3), and rate of study (H4), significantly influences the attitudes of students from Montenegro and North Macedonia towards environmental awareness, safety, and knowledge. Research findings indicate significant variations in environmental awareness and knowledge perception among students in the two countries. While both Montenegro and North Macedonia face environmental challenges, differences in educational systems and socio-economic factors contribute to distinct attitudes and behaviours towards environmental issues and safety practices. This study sheds light on the importance of understanding regional differences in environmental awareness and knowledge perception among students. By identifying areas of strength and areas needing improvement, policymakers and educators can develop targeted interventions to enhance environmental education and foster a culture of sustainability in both Montenegro and North Macedonia. Graphical abstract

Earthquakes are a rather complex natural phenomenon that cannot be prevented, and their effects can be catastrophic and have profound implications on various economic sectors (especially tourism). This study investigates the relationships between subjective factors (gender, age, education, previous experience, and disaster anxiety), the perceived travel risk, and the travel intention of tourists from Serbia to destinations in Türkiye. The pilot study was done in March 2023 with 110 respondents from the Faculty of Science, Department of Geography, Tourism, and Hotel Management, Novi Sad. After the validation of the instruments, the main survey was conducted in the period from March to June 2023. The subjects of interest were residents of Serbia over the age of 18. The data from this study are analyzed using the confirmatory factor analysis and path analyses. This study aims to enhance the understanding of perceived risk and travel intention, specifically focusing on Türkiye. The assessed outcome relates to how tourists perceive three specific categories of risk when traveling to destinations with a high risk of natural disasters, such as earthquake-prone areas. The findings suggest that older respondents tend to perceive lower physical and financial travel risks, even though the influence of age on the perception of socio-psychological risks was inconclusive. Further results reveal that individuals with prior experience tend to hold a heightened perception of physical, financial, and socio-psychological risks. An examination of the relationship between disaster anxiety and perceived travel risks indicates that physical, financial, and socio-psychological risks exert a negative influence on travel intention. Thus, this study may provide a conceptual foundation for both theoretical and practical implications for the improvement of risk management techniques at a specific travel destination in areas prone to earthquake hazards.

The subject of the research represents the application of remote sensing in monitoring land degradation in the municipality of Stanari in Bosnia and Herzegovina (B&H). The aim of the study is to identify spatial changes during the research period (2017–2023) by processing remote sensing “products.” Within the changes in land use, the focus is placed on alterations resulting from surface mineral resource mining activities. The total approved exploitation area amounts to 3841.08 ha, covering almost a quarter of the municipality (23.89%). Monitoring changes in land use was conducted through the processing of Sentinel-2 images using supervised classification (SC). The classification results were compared with the Dynamic World (DW) dataset. Results indicate significant losses in forested areas, reduced by −7.23% (DW) or −2.43% (SC) at the municipal level and −11.48% (DW) or −5.90% (SC) within the exploitation area. Spatial extents of deforestation were identified and analyzed based on processing the Hansen Global Forest Data Change dataset. The deforestation area, caused by mining activity in B&H over the research period (2001–2021), amounts to 977.94 ha, with 264.25 ha (27.02%) within the Stanari municipality. Over 90% of the cleared forest area is within the exploitation area. High erosion coefficient values ( Z ) were recorded within the approved exploitation area, coinciding with the spatial coverage of deforestation. Additionally, results obtained using an empirical method for studying mechanical water erosion ( W y ) indicate a high intensity within the exploitation area. For the approved exploitation area, possibilities for the restoration of degraded land were analyzed, including an overview of activities conducted so far and mapping some of the previously reclaimed areas. The research contributes to a better understanding of spatial changes resulting from mining activities, and the presented data are significant for numerous practical issues, such as sustainable land use planning, spatial planning, protection of forest ecosystems, and the environment.

The research subject is the application of geographic information systems (GIS) in assessing land suitability for agriculture in the Sana River Basin in Bosnia and Herzegovina. The aim of the research is to apply the analytic hierarchy process (AHP) in identifying suitable areas for agricultural production. Within the AHP framework, the following factors were considered: pedology, land use, elevation, slope, aridity index, and distance from rivers. The results of the suitability assessment underwent reclassification (RP) and cluster analysis processes (CAPs). It was found that very unsuitable land (1) covers an area of 0.15% (RP) or 5.83% (CAP), unsuitable land (2) covers 3.44% (RP) or 17.52% (CAP), conditionally suitable land (3) covers 32.11% or 28.47% (CAP), suitable land (4) covers 56.29% or 28.57% (CAP), and very suitable land (5) covers 7.98% (RP) or 19.59% (CAP). At the study area level, a supervised classification process was conducted to identify land use classes: meadows/pastures, water, forest, agricultural, and built-up areas. RP and CAP results were overlaid with supervised classification results to determine the amount of land used for agricultural purposes within each suitability class. It was determined that currently, for agricultural purposes, 0.04 km 2 (RP) or 0.88 km 2 (CAP) of very unsuitable land (1) is used, 0.41 km 2 (RP) or 7.28 km 2 (CAP) of unsuitable land (2), 15.75 km 2 (RP) or 27.52 km 2 (CAP) of conditionally suitable land (3), 185.15 km 2 (RP) or 107.06 km 2 (CAP) of suitable land (4), and 42.99 km 2 (RP) or 101.65 km 2 (CAP) of very suitable land (5). The research findings hold substantial importance in elucidating both the potential and constraints of land use practices as a vital natural resource within agriculture. They also have practical importance for relevant institutions in terms of agricultural sector development and making timely land use planning decisions for sustainable development.

This study presents a comprehensive analysis of flash flood susceptibility in the Kratovska Reka catchment area of Northeastern North Macedonia, integrating Geographic Information System, remote sensing, and field survey data. Key factors influencing flash flood dynamics, including Slope, Lithology, Land use, and Vegetation index, were investigated to develop the Flash Flood Potential Index (FFPI). Mapping slope variation using a 5-m Digital Elevation Model (DEM) revealed higher slopes in eastern tributaries compared to western counterparts. Lithological units were classified based on susceptibility to erosion processes, with clastic sediments identified as most prone to flash floods. Land use analysis highlighted non-irrigated agricultural surfaces and areas with sparse vegetation as highly susceptible. Integration of these factors into the FFPI model provided insights into flash flood susceptibility, with results indicating a medium risk across the catchment. The average value of the FFPI is 1.9, considering that the values range from 1 to 5. Also, terrains susceptible to flash floods were found to be 49.34%, classified as medium risk. Field survey data validated the model, revealing a significant overlap between hotspot areas for flash floods and high-risk regions identified by the FFPI. An average FFPI coefficient was calculated for each tributary (sub-catchment) of the Kratovska Reka. According to the model, Latišnica had the highest average coefficient of susceptibility to potential flash floods, with a value of 2.16. These findings offer valuable insights for spatial planning and flood risk management, with implications for both local and national-scale applications. Future research directions include incorporating machine learning techniques to enhance modeling accuracy and reduce subjectivity in assigning weighting factors.

Ensuring the quality protection of geospatial elements entails environmental control, a task unattainable without precise measurement results. This article aims to conduct a spatio-temporal analysis of soil degradation and vegetation status within the influence zone of the Kolubara Mining Basin in Serbia. Remote sensing is employed to assess vulnerability to erosion using the erosion potential method. A geographic information system environment is utilized to generate an erosion map, illustrating erosive processes across different time periods, particularly comparing the present situation (2022) to 1983. Results indicate that observed areas are experiencing erosion due to changes in land use. Furthermore, this study investigates the use of the normalized difference vegetation index to monitor vegetation cover changes from 1992 to 2022. The objective is to demonstrate that these methods effectively depict degradation levels and vegetation status in the area. This comprehensive overview provides insights into the changes occurring across the analyzed years. Such insights are crucial for informing future efforts to restore the region to its natural state prior to lignite mining.

Landslides and slope processes constitute one of the most frequent natural hazards in valleys near major rivers and mountainous regions. The surface layer, characterized by its relatively loose composition, is prone to sliding due to a combination of distinct natural and human-related factors. Specific sections along the right bank of the Danube River in Smederevo city exhibit significant susceptibility to landslide activation, often leading to substantial material losses and posing a risk to the local population. The initial step in the provided research involves analyzing existing literature and mapping landslides within the study area. The initial analysis covers both natural conditions and anthropogenic activities. The second step includes establishing a geospatial database in the Geographic Information System and generating eight thematic maps. In the third step, different weight coefficients were assigned to the criteria, which facilitated the creation of the Landslide Susceptibility Index using the Best–Worst Method. Subsequently, in the fourth step, a composite map illustrating landslide susceptibility was produced. According to this research, about 4% of the territory of Smederevo, or 19.3 km 2 , is highly or very highly susceptible to landslides. These localities are located on the right bank of the Danube River and around the Ralja River. Receiver operating characteristic-area under the curve value indicates very high predictive power (approximately 1), thus suggesting the reliability of the used methodology. This visualization of areas highly prone to such occurrences empowers policymakers to implement more effective environmental protection measures and institute sustainable management practices for agricultural parcels in this region. Also, the provided research represents the inaugural integration of advanced remote sensing techniques and interdisciplinary investigations, offering deeper insights into landslide activity in the study area and yielding more comprehensive results.

Wildfires pose a significant ecological, environmental, and socioeconomic challenge in southeastern Europe. The preservation of wildlands is not only essential but also a foremost priority for Montenegro, a country recognized as the world’s first ecological state. Consequently, the development of optimal methodologies and models is of paramount importance to enhance fire protection measures. With this objective in mind, this study strives to create a wildfire susceptibility model on a national scale for Montenegro. The study employed seven natural and anthropogenic causative criteria: vegetation type; aspect; slope; elevation; climate classification; distance from road; and population. The modeling process integrates both natural and anthropogenic causal criteria, employing the Fuzzy Analytic Hierarchy Process (F-AHP) and Frequency Ratio (FR) within geoinformatics environment. The outcomes of the F-AHP model reveal that 72.84% of the total area is categorized as having high to very high susceptibility. Conversely, based on the FR model, only 29.07% of the area falls within these susceptibility levels. In terms of validation, the area under curvature values indicates good performance of the F-AHP model. In contrast, the FR model demonstrates poor performance. These novel findings, pertaining to Montenegro at a national scale, offer valuable insights for preemptive wildfire safeguarding efforts. Moreover, the methodologies employed, with necessary modifications, hold potential for application in geographically diverse regions.

The objective of the study is to investigate the current state of the canyons in the northern part of Montenegro, their potential for sustainable development, which could be achieved through canyoning as an attractive tourist attraction, and to assess the area’s geotourism potential. The canyons encompassed in this research are the Nevidio Canyon, the Tara Canyon, the Grlja Canyon, and the canyon of the river Ibar. The research was carried out using the modified Geosite Assessment Model, which includes tourists’ opinions on the significance of indicators in the assessment process. The obtained results show that all four canyons possess significant scientific, educational, and aesthetic values for the development of canyoning tourism. Since surveyed tourists pointed out not only the advantages but disadvantages of these geosites, these findings should be further used for the valorization and geoconservation of the geosite and provide a more favorable deal for the arrival of as many tourists as possible. In the future, investigated geosites should be improved with tourist content and activities, such as interpretive boards for tourists, expert guides, organized visits, tourist infrastructure, and promotion. Successful activities in these critical areas could contribute to sustainable geotourism being one of the key economically beneficial activities of the local population that will develop local communities through the arrival of a larger number of domestic and foreign tourists.

Sokobanja is a well-known spa centre in East Serbia, whose popularity is mostly based on its natural heritage (thermo-mineral springs, waterfalls, canyons, caves, and pits). However, built heritage also offers significant potential for developing geotourism. This article aims to assess the geoheritage values of the geocultural site Sokograd fortress to support geotourism development in this area. For the assessment of geotourism potentials, the urban geoheritage assessment model (UGAM) was applied. To support the criteria of UGAM (e.g. variety of geodiversity and educational potentials), a macroscopic mineralogical–petrographical observation of the building stone was performed. The results revealed significant educational potentials, especially concerning petrodiversity, with sedimentary rocks (limestone, sandstone, tufa, and conglomerates). By comparing the obtained results with the local geology, it is recognized that the building stone was mainly of local provenance. The UGAM parameters, such as geocultural and ecological values, as well as a variety of geodiversity, confirmed that Sokograd has great potential for urban geotourism development. After all, the assessment of degradation risk was performed and revealed that tourism development cannot cause serious threats to the site, but tourism has to be adequately regulated and managed in a sustainable way. The results of this study can provide information to policymakers, local governments, and other interested stakeholders on whether and how to develop urban geotourism at the Sokograd fortress in the upcoming period.

Due to favorable natural conditions and human impact, the territory of North Macedonia is very susceptible to natural hazards. Steep hillslopes combined with soft rocks (schists on the mountains; sands and sandstones in depressions), erodible soils, semiarid continental climate, and sparse vegetation cover give a high potential for soil erosion and landslides. For this reason, this study presents a multi-hazard approach to geohazard modeling on the national extent in the example of North Macedonia. Utilizing Geographic Information Systems, relevant data about the entire research area were employed to analyze and assess soil erosion and susceptibility to landslides and identify areas prone to both hazards. Using the Gavrilović Erosion Potential Method (EPM), an average value of 0.36 was obtained for the erosion coefficient Z , indicating low to moderate susceptibility to erosion. However, a significant area of the country (9.6%) is susceptible to high and excess erosion rates. For the landslide susceptibility assessment (LSA), the Analytical hierarchy process approach is combined with the statistical method (frequency ratio), showing that 29.3% of the territory belongs to the zone of high and very high landslide susceptibility. Then, the accuracy assessment is performed for both procedures (EPM and LSA), showing acceptable reliability. By overlapping both models, a multi-hazard map is prepared, indicating that 22.3% of North Macedonia territory is highly susceptible to erosion and landslides. The primary objective of multi-hazard modeling is to identify and delineate hazardous areas, thereby aiding in activities to reduce the hazards and mitigate future damage. This becomes particularly significant when considering the impact of climate change, which is associated with increased landslide and erosion susceptibility. The approach based on a national level presented in this work can provide valuable information for regional planning and decision-making processes.

Enhancing resilience against seismic hazards in earthquake-prone regions is essential for reducing the devastating impacts of disasters. Seismic resilience refers to a community’s ability to withstand and recover from earthquake impacts, while preparedness gaps are the areas where current measures are insufficient to effectively respond to or mitigate earthquake damage. This study focuses on Montenegro – a region with frequent seismic activity – aiming to assess resilience levels, identify critical gaps in preparedness, and evaluate the effectiveness of existing response strategies. Using qualitative methods, including semi-structured interviews, the research gathered insights from residents of Montenegro’s most vulnerable cities: Nikšić, Podgorica, Bar, Kotor, Cetinje, Budva, Herceg Novi, and Berane. Participants, chosen for their first-hand experience with significant earthquake impacts, provided valuable perspectives on various aspects of resilience, from local government response to individual preparedness. This research revealed significant disparities in resilience across communities: for instance, approximately 62.5% of the respondents highlighted inadequate education as a barrier to effective earthquake preparedness, and only 37.5% reported awareness of basic earthquake response procedures. Furthermore, while some communities, such as urban areas with accessible services, reported higher preparedness levels, rural areas showed deficiencies, with 50% of the respondents from these areas identifying a lack of organized drills and limited public awareness initiatives. These findings underscore the urgent need for community-specific preparedness programs and enhancements in both structural resilience and public education to bolster community readiness effectively. Also, findings highlight the need for customized preparedness programs tailored to specific community needs, alongside improvements in structural safety measures and educational outreach. The study underscores the importance of a comprehensive approach involving detailed risk assessments, community-focused preparedness training, and stronger public awareness initiatives. Furthermore, the study calls for enhanced local government capabilities to sustain proactive response measures, including rapid mobilization of emergency resources and regular disaster simulations, to build long-term resilience across communities.

In this study, the soil CO 2 emission was analysed at the level II ICP Forests monitoring plot in Serbia in the pedunculate oak forest. Two plots of pedunculate oak ( Quercus robur L.) were selected for this study. The main question was to determine the differences in the impact of management (human impact) on CO 2 emission. Different time periods were compared to identify the main factors affecting soil CO 2 emission. Sampling was done by chambers. During the study period, climate indicators were quite different. A strong positive correlation between the soil temperature and soil CO 2 emission, as well as a strong negative correlation between the soil moisture and soil CO 2 emission, was found in the spring aspect ( Plot ). In other cases, a moderate to weak correlation was found. Multiple linear regressions showed that CO 2 emission from soil was primarily controlled by soil moisture. Increasing soil water content had a positive effect on soil respiration (except in spring). The effect of soil temperature appeared in the multiple regressions as a secondary factor during the period studied, and an increase in temperature resulted in a decrease in soil respiration (except in spring).

In this study, in a pioneering effort, glomalin proteins were extracted and geochemically characterized from soil in Serbia. Standard chemical (dry combustion, Walkley-Black) and spectroscopic methods (fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), scanning electron microscope (SEM)) were used to gain insight into the glomalin proteins. Samples from the City of Novi Sad (Serbia) were used for characterization and comparison. The soil contained an average of 17 mg/g of glomalin, representing ≈21% of the soil organic matter. DLS zeta potential analysis and the FTIR spectra reveal two significant differences before and after glomalin extraction, indicating a relationship between sand fractions and organic matter that affects particle aggregation and erosion potential. A comparison of SEM images and DLS results reveals that the glomalin extract consists of two particle size groups (0.08–1 and 6 µm), suggesting that the extraction process isolates only a smaller fraction of proteins and less tightly bound particles, indicating that soil aggregation is influenced by both mineralogy and the characteristics of organic matter. Hence, our research raises important questions about the role of glomalin in mitigating soil degradation processes, particularly soil erosion. Our study will enhance the overall understanding of glomalin, inspire future research, and prove beneficial for the sustainable restoration of degraded lands.

The main goal of this study is to find out if there are any differences between Grašac wines from two different locations of the Fruška Gora Mountain and to further explore why these differences (if they exist) occur. To achieve this, we selected one vineyard in Sremski Karlovci and one in Neštin where we have analyzed the topography features, soil, and climate at both sites as well as the chemical analysis of the wines from these sites from three different vintages (2017–2019). Additionally, a sensory analysis was also done for seven consecutive vintages (2016–2022). The results reveal that the wines from Sremski Karlovci have a higher aroma intensity on the nose and dominant primary fruit aromas while they are young. These characteristics tend to drop quickly with age. On the other hand, Grašac wines from Neštin tend to age better, becoming fuller bodied, more intense, complex, with tertiary aromas on the nose and palate and with a longer finish. The key differences between these two locations are connected to the thick loess deposits and the amount of available water at the analyzed sites.

This research is dedicated to a comprehensive exploration of the strengths and weaknesses inherent in the legal and institutional measures established to safeguard cultural heritage in the Republic of Serbia against the adverse effects of disasters, including earthquakes, landslides, rockfalls, floods, torrents, storms, hail, and forest fires. The study seeks to identify key challenges and shortcomings within the existing legal and institutional framework while also highlighting and analyzing best practices and potential avenues for improvement in the protection system. The research posits a preliminary hypothesis suggesting that significant challenges exist within the current framework, potentially hindering effective response and recovery efforts following natural hazards. Data collection involved semi-structured interviews with field experts and an in-depth analysis of existing documentation. These methods were aimed at gathering critical data and insights to enhance the understanding of systemic issues and contribute to developing practical, viable solutions. The analysis and processing of the collected data were conducted using ATLAS. ti software, enabling a detailed and systematic examination of qualitative information. Moreover, assessing the current capacity of institutions to respond swiftly and effectively to natural hazards that threaten cultural heritage formed a central aspect of this study. The findings reveal notable deficiencies in the legal framework, inadequate institutional capacities, limited resources, and insufficient training for disaster response. The results underscore the pressing need for improved inter-institutional cooperation and the development of technical and logistical capabilities. To address these issues, the study recommends aligning legal frameworks with international standards, securing increased funding for technical resources, and implementing specialized training programs for institutional staff. This article makes a significant contribution to advancing the understanding and enhancement of the cultural heritage protection system in Serbia, offering actionable insights and a robust foundation for further research and strategic development in this critical area.