Home Physical Sciences Cathodoluminescence images and trace element compositions of fluorapatite from the Hongge layered intrusion in SW China: A record of prolonged crystallization and overprinted fluid metasomatism
Article
Licensed
Unlicensed Requires Authentication

Cathodoluminescence images and trace element compositions of fluorapatite from the Hongge layered intrusion in SW China: A record of prolonged crystallization and overprinted fluid metasomatism

  • Chang-Ming Xing EMAIL logo and Christina Yan Wang
Published/Copyright: July 19, 2017
Become an author with De Gruyter Brill
Author Information
American Mineralogist
From the journal American Mineralogist Volume 102 Issue 7

Abstract

Cathodoluminescence (CL) and trace element analyses were performed for fluorapatite from the gabbro and Fe-Ti oxide ores in the upper zone of the Hongge Fe-Ti oxide-bearing, mafic-ultramafic layered intrusion in SW China. The fluorapatite is closely associated with Fe-Ti oxides and interstitial to plagioclase and clinopyroxene. The fluorapatite grains in one thin section vary from ~10 to 800 mm in width and ~50 to 1200 μm in length. Coarse-grained fluorapatite crystals (>200 in width) in the same thin section show both simple and complex CL images. The coarse-grained fluorapatite crystals with simple CL images show discontinuous, thin dark rims along grain boundaries, whereas those with complex images show clearly bright veinlets across the grains. On the other hand, fine-grained fluorapatite crystals (<200 μm in width) show complex CL images and can be divided into four types, i.e., concentric, chaotic, banded, and overall dark. The concentric type shows distinctly bright core surrounded by dark mantle that is irregularly zoned, whereas the chaotic type shows disordered bright and dark sectors in the interior with a thin dark rim. The banded type shows unevenly distributed bright and dark bands. The overall dark type shows a relatively dark and uneven image. Fluorapatite grains contain 1.84–2.74 wt% F, 0.07–0.19 wt% Cl, and 0.86–1.63 wt% OH. Coarse-grained fluorapatite grains have total rare earth elements (REE) concentrations ranging from 2278 to 3008 ppm and Sr/Y of 9 to 13. Fine-grained fluorapatite grains have relatively high REE (2242–4687 ppm) and low Sr/Y of 6 to 14 in the bright cores, sectors, and bands and relatively low REE (1881–2728 ppm) and high Sr/Y of 9 to 15 in the dark mantles, sectors, and rims under CL imaging. On the thin section scale, the bright sections under CL imaging for fine-grained fluorapatite have much higher REE contents than those for similar bright CL images for coarse-grained fluorapatite. The highly variable REE concentrations among fluorapatite grains and the sections within a single fluorapatite are attributed to a prolonged crystallization process and overprint by fluid metasomatism. The coarse-grained fluorapatite may have crystallized earlier than fine-grained fluorapatite. Then variable degrees of hydrothermal metasomatism released REE from the fine-grained fluorapatite so that diverse CL images developed in the crystals. This study reveals that magmatic apatite from a layered intrusion can be intensively modified by later-stage fluid-induced metasomatism in both trace element composition and CL image texture. Reconstruction of primary melt compositions using apatite from layered intrusions should therefore be treated with caution.

Keywords: Fluorapatite; cathodoluminescence image; trace element; fluid metasomatism; mafic-ultramafic layered intrusion

Acknowledgments

This study was financially supported by the Strategic Priority Research Program (B) of the Chinese Academy of Sciences (XDB18000000), NFSC grants No. 41325006, 41473017, and 41502048. Linli Chen and Congying Li are thanked for providing assistance during CL imaging and LA-ICP-MS analyses. We are grateful to Grant Cawthorn and the other anonymous reviewer, and associate editor Daniel Harlov, who provided critical and constructive comments that improved the quality of this manuscript.

References cited

Barbarand, J., and Pagel, M. (2001) Cathodoluminescence study of apatite crystals. American Mineralogist, 86(4), 473–484.10.2138/am-2001-0411Search in Google Scholar

Barnes, S.J. (1986) The effect of trapped liquid crystallization on cumulus mineral compositions in layered intrusions. Contributions to Mineralogy and Petrology, 93(4), 524–531.10.1007/BF00371722Search in Google Scholar

Bindeman, I.N., Davis, A.M., and Drake, M.J. (1998) Ion microprobe study of plagioclase-basalt partition experiments at natural concentration levels of trace elements. Geochimica et Cosmochimica Acta, 62(7), 1175–1193.10.1016/S0016-7037(98)00047-7Search in Google Scholar

Bonyadi, Z., Davidson, G.J., Mehrabi, B., Meffre, S., and Ghazban, F. (2011) Significance of apatite REE depletion and monazite inclusions in the brecciated Se-Chahun iron oxide-apatite deposit, Bafq district, Iran: insights from paragenesis and geochemistry. Chemical Geology, 281, 253–269.10.1016/j.chemgeo.2010.12.013Search in Google Scholar

Broska, I., Ravna, E.J.K., Vojtko, P., Janák, M., Konečný, P., Pentrák, M., Bačik, P., Luptáková, J., and Kullerud, K. (2014) Oriented inclusions in apatite in a post-UHP fluid-mediated regime (Troms⊘ Nappe, Norway). European Journal of Mineralogy, 26(5), 623–634.10.1127/0935-1221/2014/0026-2396Search in Google Scholar

Cawthorn, R.G. (1994) Formation of chlor- and fluor-apatite in layered intrusions. Mineralogical Magazine, 58, 299–306.10.1180/minmag.1994.058.391.12Search in Google Scholar

Cawthorn, R.G. (2013) Rare earth element abundances in apatite in the Bushveld Complex—A consequence of the trapped liquid shift effect. Geology, 41(5), 603–606.10.1130/G34026.1Search in Google Scholar

Filippelli, G.M., and Delaney, M.L. (1993) The effects of manganese (II) and iron (II) on the cathodoluminescence signal in synthetic apatite. Journal of Sedimentary Research, 63(1), 167–173.Search in Google Scholar

Harlov, D.E. (2015) Apatite: a fingerprint for metasomatic processes. Elements, 11(3), 171–176.10.2113/gselements.11.3.171Search in Google Scholar

Harlov, D.E., and Förster, H.-J. (2003) Fluid-induced nucleation of (Y+REE)-phosphate minerals within apatite: Nature and experiment. Part II. Fluorapatite. American Mineralogist, 88(8-9), 1209–1229.10.2138/am-2003-8-905Search in Google Scholar

Harlov, D.E., Förster, H.-J., and Nijland, T.G. (2002a) Fluid-induced nucleation of (Y+REE)-phosphate minerals within apatite: Nature and experiment. Part I. Chlorapatite. American Mineralogist, 87(2-3), 245–261.10.2138/am-2002-2-306Search in Google Scholar

Harlov, D.E., Andersson, U.B., Förster, H.-J., Nyström, J.O., Dulski, P., and Broman, C. (2002b) Apatite-monazite relations in the Kiirunavaara magnetite-apatite ore, northern Sweden. Chemical Geology, 191(1), 47–72.10.1016/S0009-2541(02)00148-1Search in Google Scholar

Harlov, D.E., Wirth, R., and Förster, H.-J. (2005) An experimental study of dissolution-reprecipitation in fluorapatite: fluid infiltration and the formation of monazite. Contributions to Mineralogy and Petrology, 150(3), 268–286.10.1007/s00410-005-0017-8Search in Google Scholar

Harlov, D.E., Meighan, C.J., Kerr, I.D., and Samson, I.M. (2016) Mineralogy, chemistry, and fluid-aided evolution of the Pea Ridge Fe oxide-(Y+ REE) deposit, southeast Missouri, USA. Economic Geology, 111(8), 1963–1984.10.2113/econgeo.111.8.1963Search in Google Scholar

Hart, S.R., and Dunn, T. (1993) Experimental cpx/melt partitioning of 24 trace elements. Contributions to Mineralogy and Petrology, 113(1), 1–8.10.1007/BF00320827Search in Google Scholar

Holness, M.B., Tegner, C., Nielsen, T.F., Stripp, G., and Morse, S.A. (2007) A textural record of solidification and cooling in the Skaergaard intrusion, East Greenland. Journal of Petrology, 48(12), 2359–2377.10.1093/petrology/egm064Search in Google Scholar

Kempe, U., and Götze, J. (2002) Cathodoluminescence (CL) behaviour and crystal chemistry of apatite from rare-metal deposits. Mineralogical Magazine, 66(1), 151–172.10.1180/0026461026610019Search in Google Scholar

Li, X., and Zhou, M.-F. (2015) Multiple stages of hydrothermal REE remobilization recorded in fluorapatite in the Paleoproterozoic Yinachang Fe-Cu-(REE) deposit, Southwest China. Geochimica et Cosmochimica Acta, 166, 53–73.10.1016/j.gca.2015.06.008Search in Google Scholar

Lisowiec, K., Słaby, E., and Götze, J. (2013) Cathodoluminescence (CL) of apatite as an insight into magma mixing in the granitoid pluton of Karkonosze, Poland. Conference on Raman and Luminescence Spectroscopy in the Earth Sciences, p. 67–68. University of Vienna, Austria.Search in Google Scholar

Liu, Y., Hu, Z., Gao, S., Günther, D., Xu, J., Gao, C., and Chen, H. (2008) In situ analysis of major and trace elements of anhydrous minerals by LA-ICP-MS without applying an internal standard. Chemical Geology, 257(1), 34–43.10.1016/j.chemgeo.2008.08.004Search in Google Scholar

Ma, Y., Ji, X.T., Li, J.C., Huang, M., and Kan, Z.Z. (2003) Mineral Resources of the Panzhihua Region. Sichuan Science and Technology Press, Chengdu. 275 pp. (in Chinese).Search in Google Scholar

McDonough, W.F., and Sun, S.-S. (1995) The composition of the Earth. Chemical Geology, 120(3), 223–253.10.1016/S0074-6142(01)80077-2Search in Google Scholar

Meurer, W., and Meurer, M. (2006) Using apatite to dispel the “trapped liquid” concept and to understand the loss of interstitial liquid by compaction in mafic cumulates: an example from the Stillwater Complex, Montana. Contributions to Mineralogy and Petrology, 151(2), 187–201.10.1007/s00410-005-0054-3Search in Google Scholar

Murray, J.R., and Oreskes, N. (1997) Uses and limitations of cathodoluminescence in the study of apatite paragenesis. Economic Geology, 92(3), 368–376.10.2113/gsecongeo.92.3.368Search in Google Scholar

Namur, O., Charlier, B., and Holness, M.B. (2012) Dual origin of Fe-Ti-P gabbros by immiscibility and fractional crystallization of evolved tholeiitic basalts in the Sept Iles layered intrusion. Lithos, 154, 100–114.10.1016/j.lithos.2012.06.034Search in Google Scholar

Nielsen, R.L., Gallahan, W.E., and Newberger, F. (1992) Experimentally determined mineral-melt partition coefficients for Sc, Y and REE for olivine, orthopyroxene, pigeonite, magnetite and ilmenite. Contributions to Mineralogy and Petrology, 110(4), 488–499.10.1007/BF00344083Search in Google Scholar

Otten, M.T. (1984) The origin of brown hornblende in the Artfjället gabbro and dolerites. Contributions to Mineralogy and Petrology, 86(2), 189–199.10.1007/BF00381846Search in Google Scholar

Pan, Y., Fleet, M.E., and Macrae, N.D. (1993) Oriented monazite inclusions in apatite porphyroblasts from the Hemlo gold deposit, Ontario, Canada. Mineralogical Magazine, 57, 697–707.10.1180/minmag.1993.057.389.14Search in Google Scholar

Prowatke, S., and Klemme, S. (2006) Trace element partitioning between apatite and silicate melts. Geochimica et Cosmochimica Acta, 70(17), 4513–4527.10.1016/j.gca.2006.06.162Search in Google Scholar

Reynolds, I.M. (1985) The nature and origin of titaniferous magnetite-rich layers in the upper zone of the Bushveld Complex; a review and synthesis. Economic Geology, 80(4), 1089–1108.10.2113/gsecongeo.80.4.1089Search in Google Scholar

Ridolfi, F., and Renzulli, A. (2012) Calcic amphiboles in calc-alkaline and alkaline magmas: thermobarometric and chemometric empirical equations valid up to 1,130 °C and 2.2 GPa. Contributions to Mineralogy and Petrology, 163(5), 877–895.10.1007/s00410-011-0704-6Search in Google Scholar

Roeder, P.L., MacArthur, D., Ma, X.-P., Palmer, G.R., and Mariano, A.N. (1987) Cathodoluminescence and microprobe study of rare-earth elements in apatite. American Mineralogist, 72(7-8), 801–811.Search in Google Scholar

She, Y.-W., Song, X.-Y., Yu, S.-Y., Chen, L.-M., and Zheng, W.-Q. (2016) Apatite geochemistry of the Taihe layered intrusion, SW China: Implications for the magmatic differentiation and the origin of apatite-rich Fe-Ti oxide ores. Ore Geology Reviews, 78, 151–165.10.1016/j.oregeorev.2016.04.004Search in Google Scholar

Tegner, C., Cawthorn, R.G., and Kruger, F.J. (2006) Cyclicity in the Main and Upper Zones of the Bushveld Complex, South Africa: crystallization from a zoned magma sheet. Journal of Petrology, 47(11), 2257–2279.10.1093/petrology/egl043Search in Google Scholar

Tollari, N., Barnes, S.-J., Cox, R., and Nabil, H. (2008) Trace element concentrations in apatites from the Sept-Îles Intrusive Suite, Canada-implications for the genesis of nelsonites. Chemical Geology, 252(3), 180–190.10.1016/j.chemgeo.2008.02.016Search in Google Scholar

Van Tongeren, J., and Mathez, E. (2012) Large-scale liquid immiscibility at the top of the Bushveld Complex, South Africa. Geology, 40(6), 491–494.10.1130/G32980.1Search in Google Scholar

Von Gruenewaldt, G. (1993) Ilmenite-apatite enrichments in the upper zone of the Bushveld Complex: A major titanium-rock phosphate resource. International Geology Review, 35(11), 987–1000.10.1080/00206819309465570Search in Google Scholar

Wang, C.Y., and Zhou, M.-F. (2013) New textural and mineralogical constraints on the origin of the Hongge Fe-Ti-V oxide deposit, SW China. Mineralium Deposita, 48, 787–798.10.1007/s00126-013-0457-4Search in Google Scholar

Webster, J.D., and Piccoli, P.M. (2015) Magmatic apatite: a powerful, yet deceptive, mineral. Elements, 11(3), 177–182.10.2113/gselements.11.3.177Search in Google Scholar

Received: 2016-11-26
Accepted: 2017-3-14
Published Online: 2017-7-19
Published in Print: 2017-7-26

© 2017 by Walter de Gruyter Berlin/Boston

Articles in the same Issue

  1. Editorial
  2. A new high JIF for American Mineralogist (by all early indications), why you shouldn’t care, and a note on values
  3. Highlights and Breakthroughs
  4. Sapphire, a not so simple gemstone
  6. Radon emanation coefficients of several minerals: How they vary with physical and mineralogical properties
  7. Actinides in geology, energy, and the environment
  8. Cabvinite, Th2F7(OH)⋅3H2O, the first natural actinide halide
  9. Special collection: apatite: a common mineral, uncommonly versatile
  10. Cathodoluminescence images and trace element compositions of fluorapatite from the Hongge layered intrusion in SW China: A record of prolonged crystallization and overprinted fluid metasomatism
  11. Special Collection: Nanominerals and Mineral Nanoparticles
  12. Structural characterization of marine nano-quartz in chalk and flint from North Sea Tertiary chalk reservoirs for oil and gas
  13. Special collection: Geology and geobiology of lassen volcanic national park
  14. Secondary minerals associated with Lassen fumaroles and hot springs: Implications for martian hydrothermal deposits
  16. Phillipsite and Al-tobermorite mineral cements produced through low-temperature water-rock reactions in Roman marine concrete
  18. The origin of needle-like rutile inclusions in natural gem corundum: A combined EPMA, LA-ICP-MS, and nanoSIMS investigation
  20. Dehydration studies of natrolites: Role of monovalent extra-framework cations and degree of hydration
  22. Mineralogical and compositional features of rock fulgurites: A record of lightning effects on granite
  24. Formation of basic lead phases during fire-setting and other natural and man-made processes
  26. Revisiting the nontronite Mössbauer spectra
  28. Experimental evidence for the survival of augite to transition zone depths, and implications for subduction zone dynamics
  30. Hydrothermal alteration of monazite-(Ce) and chevkinite-(Ce) from the Sin Quyen Fe-Cu-LREE-Au deposit, northwestern Vietnam
  32. Diagenetic F-rich ferroan calcite and zircon in the offshore Scotian Basin, eastern Canada: Significance for understanding thermal evolution of the basin
  34. Addibischoffite, Ca2Al6Al6O20, a new calcium aluminate mineral from the Acfer 214 CH carbonaceous chondrite: A new refractory phase from the solar nebula
  35. Letter
  36. 17O NMR evidence of free ionic clusters Mn+ CO32− in silicate glasses: Precursors for carbonate-silicate liquids immiscibility
  38. New Mineral Names
  40. Erratum
https://doi.org/10.2138/am-2017-6028
Keywords for this article
Fluorapatite; cathodoluminescence image; trace element; fluid metasomatism; mafic-ultramafic layered intrusion

Articles in the same Issue

  1. Editorial
  2. A new high JIF for American Mineralogist (by all early indications), why you shouldn’t care, and a note on values
  3. Highlights and Breakthroughs
  4. Sapphire, a not so simple gemstone
  6. Radon emanation coefficients of several minerals: How they vary with physical and mineralogical properties
  7. Actinides in geology, energy, and the environment
  8. Cabvinite, Th2F7(OH)⋅3H2O, the first natural actinide halide
  9. Special collection: apatite: a common mineral, uncommonly versatile
  10. Cathodoluminescence images and trace element compositions of fluorapatite from the Hongge layered intrusion in SW China: A record of prolonged crystallization and overprinted fluid metasomatism
  11. Special Collection: Nanominerals and Mineral Nanoparticles
  12. Structural characterization of marine nano-quartz in chalk and flint from North Sea Tertiary chalk reservoirs for oil and gas
  13. Special collection: Geology and geobiology of lassen volcanic national park
  14. Secondary minerals associated with Lassen fumaroles and hot springs: Implications for martian hydrothermal deposits
  16. Phillipsite and Al-tobermorite mineral cements produced through low-temperature water-rock reactions in Roman marine concrete
  18. The origin of needle-like rutile inclusions in natural gem corundum: A combined EPMA, LA-ICP-MS, and nanoSIMS investigation
  20. Dehydration studies of natrolites: Role of monovalent extra-framework cations and degree of hydration
  22. Mineralogical and compositional features of rock fulgurites: A record of lightning effects on granite
  24. Formation of basic lead phases during fire-setting and other natural and man-made processes
  26. Revisiting the nontronite Mössbauer spectra
  28. Experimental evidence for the survival of augite to transition zone depths, and implications for subduction zone dynamics
  30. Hydrothermal alteration of monazite-(Ce) and chevkinite-(Ce) from the Sin Quyen Fe-Cu-LREE-Au deposit, northwestern Vietnam
  32. Diagenetic F-rich ferroan calcite and zircon in the offshore Scotian Basin, eastern Canada: Significance for understanding thermal evolution of the basin
  34. Addibischoffite, Ca2Al6Al6O20, a new calcium aluminate mineral from the Acfer 214 CH carbonaceous chondrite: A new refractory phase from the solar nebula
  35. Letter
  36. 17O NMR evidence of free ionic clusters Mn+ CO32− in silicate glasses: Precursors for carbonate-silicate liquids immiscibility
  38. New Mineral Names
  40. Erratum
Sign up now to receive a 20% welcome discount
Institutional Access
How does access work?
Have an idea on how to improve our website?
Please write us.
© 2026 De Gruyter Brill
Downloaded on 4.2.2026 from https://www.degruyterbrill.com/document/doi/10.2138/am-2017-6028/html
Scroll to top button