Combination of three global Moho density contrast models by a weighted least-squares procedure
-
Lars E. Sjöberg
and
Majid Abrehdary
Abstract
Due to different structures of the Earth’s crust and mantle, there is a significant density contrast at their boundary, the Moho Density Contrast (or shortly MDC). Frequently one assumes that the MDC is about 600 kg/m3, but seismic and gravimetric data show a considerable variation from region to region, and today there are few such studies, and global models are utterly rare.
This research determines a new global model, called MDC21, which is a weighted least-squares combination of three available MDC models, pixel by pixel at a resolution of 1° × 1°. For proper weighting among the models, the study starts by estimating lacking standard errors and (frequently high) correlations among them.
The numerical investigation shows that MDC21 varies from 21 to 504 kg/m3 in ocean areas and ranges from 132 to 629 kg/m3 in continental regions. The global average is 335 kg/m3. The standard errors estimated in ocean regions are mostly less than 40 kg/m3, while for continental regions it grows to 80 kg/m3. Most standard errors are small, but they reach to notable values in some specific regions. The estimated MDCs (as well as Moho depths) at mid-ocean ridges are small but show significant variations and qualities.
Funding source: Swedish National Space Agency
Award Identifier / Grant number: 187/18
Funding statement: This study was supported by project no. 187/18 of the Swedish National Space Agency (SNSA).
Data availability
The data sets generated and/or analyzed during the current study are available from the second author on reasonable request.
References
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© 2022 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Research Articles
- Construction of precise three-dimensional engineering control network with total station and laser tracker
- Combination of three global Moho density contrast models by a weighted least-squares procedure
- Optimization of baseline configuration in a GNSS network (Nile Delta network, Egypt) – A case study
- Investigation of determining the accuracy of spatial vectors by the satellite method in a real time mode
- Inter-annual oscillations of terrestrial water storage in Qinghai-Tibetan plateau from GRACE data
- Accuracy assessment of available airborne gravity data in the central western desert of Egypt
- Reduction as an improvement of a precise satellite positioning based on an ambiguity function
- Determination of local geometric geoid model for Kuwait
- The use of gravity data to determine orthometric heights at the Hong Kong territories
Articles in the same Issue
- Frontmatter
- Research Articles
- Construction of precise three-dimensional engineering control network with total station and laser tracker
- Combination of three global Moho density contrast models by a weighted least-squares procedure
- Optimization of baseline configuration in a GNSS network (Nile Delta network, Egypt) – A case study
- Investigation of determining the accuracy of spatial vectors by the satellite method in a real time mode
- Inter-annual oscillations of terrestrial water storage in Qinghai-Tibetan plateau from GRACE data
- Accuracy assessment of available airborne gravity data in the central western desert of Egypt
- Reduction as an improvement of a precise satellite positioning based on an ambiguity function
- Determination of local geometric geoid model for Kuwait
- The use of gravity data to determine orthometric heights at the Hong Kong territories
