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The carbonate content in high-temperature apatite; an analytical method applied to apatite from the Jacupiranga alkaline complex

1995; Mineralogical Society of America; Volume: 80; Issue: 3-4 Linguagem: Inglês

10.2138/am-1995-3-415

1945-3027

Roberto Ventura Santos, Robert N. Clayton,

Radioactive element chemistry and processing

Other| April 01, 1995 The carbonate content in high-temperature apatite: An analytical method applied to apatite from the Jacupiranga alkaline complex Roberto V. Santos; Roberto V. Santos University of Chicago, Department of the Geophysical Sciences, Chicago, IL, United States Search for other works by this author on: GSW Google Scholar Robert N. Clayton Robert N. Clayton Search for other works by this author on: GSW Google Scholar American Mineralogist (1995) 80 (3-4): 336–344. https://doi.org/10.2138/am-1995-3-415 Article history first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Roberto V. Santos, Robert N. Clayton; The carbonate content in high-temperature apatite: An analytical method applied to apatite from the Jacupiranga alkaline complex. American Mineralogist 1995;; 80 (3-4): 336–344. doi: https://doi.org/10.2138/am-1995-3-415 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search nav search search input Search input auto suggest search filter All ContentBy SocietyAmerican Mineralogist Search Advanced Search Abstract We present a method to measure carbonate content of apatite that uses infrared spectroscopy. The method was calibrated against the amount of CO2 released by reaction of apatite with phosphoric acid and may be used to study apatite with CO2 content below 1 wt%. We have applied the method to apatite from carbonatite (≈0.3–0.4 wt% CO2) and metasomatic (≈0.6-1.0 wt% CO2) and alkaline silicate (<0.3 wt% CO2) rocks from the Jacupiranga alkaline complex. The results show that higher concentration of carbonate was found in apatite related to metasomatic processes and, in particular, to metasomatism related to the intrusion of carbonatite from Jacupiranga. Major and trace elements of the analyzed apatites do not show a simple substitution mechanism that would explain the presence of carbonate in the apatite structure.In a series of exploratory laboratory experiments in which apatite was synthesized under high temperature and pressure, no clear relationship was observed between the carbonate content of the synthetic apatite and the total C content in the coexisting fluid (molecular CO2 or carbonate ions in solution). However, even though these experiments were not conclusive, they suggest that apatite coexisting with carbonate ions in solution has a CO2 content above 0.3 wt%, whereas apatite coexisting with molecular CO2 has a CO2 content <0.3 wt%. These results indicate that the CO2 content of apatite depends not only on total fluid C content, but also on the C speciation in the fluid. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not currently have access to this article.