تقرير
In situ Sr isotope analysis of apatite by LA-MC-ICPMS: constraints on the evolution of ore fluids of the Yinachang Fe-Cu-REE deposit, Southwest China
| العنوان: | In situ Sr isotope analysis of apatite by LA-MC-ICPMS: constraints on the evolution of ore fluids of the Yinachang Fe-Cu-REE deposit, Southwest China |
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| المؤلفون: | Zhao, Xin-Fu, Zhou, Mei-Fu, Gao, Jian-Feng, Li, Xiao-Chun, Li, Jian-Wei |
| بيانات النشر: | SPRINGER |
| سنة النشر: | 2015 |
| المجموعة: | Guangzhou Institute of Geochemistry: GIG OpenIR (Chinese Academy of Sciences) / 中国科学院广州地球化学研究所机构知识库 |
| مصطلحات موضوعية: | Geochemistry & Geophysics, Mineralogy, Apatite, In situ Sr isotope analysis, LA-MC-ICPMS analysis, Yinachang Fe-Cu-REE deposit, China, INITIAL SR-87/SR-86 RATIOS, U-TH-PB, YANGTZE BLOCK, SW CHINA, MINERALIZING FLUIDS, ARC-MAGMATISM, MAFIC ROCKS, GEOCHRONOLOGY, MAGNETITE, MONAZITE |
| الوصف: | Apatite is a ubiquitous accessory mineral in a variety of rocks and hydrothermal ores. Strontium isotopes of apatite are well known to retain petrogenetic information and have been widely used to investigate the origin of igneous rocks, but such attempts have rarely been made to constrain ore-forming processes of hydrothermal systems. We here report in situ LA-MC-ICPMS Sr isotope data of apatite from the similar to 1660-Ma Yinachang Fe-Cu-REE deposit, Southwest China. The formation of this deposit was coeval to the emplacement of regionally distributed doleritic intrusions within a continental-rift setting. The deposit has a paragenetic sequence consisting of sodic alteration (stage I), magnetite mineralization (stage II), Cu sulfide and REE mineralization (stage III), and final barren calcite veining (stage IV). The stage II and III assemblages contain abundant apatite, allowing to investigate the temporal evolution of the Sr isotopic composition of the ore fluids. Apatite of stage II (Apt II) is associated with fluorite, magnetite, and siderite, whereas apatite from stage III (Apt III) occurs intimately intergrown with ankerite and Cu sulfides. Apt II has Sr-87/Sr-86 ratios varying from 0.70377 to 0.71074, broadly compatible with the coeval doleritic intrusions (0.70592 to 0.70692), indicating that ore-forming fluids responsible for stage II magnetite mineralization were largely equilibrated with mantle-derived mafic rocks. In contrast, Apt III has distinctly higher Sr-87/Sr-86 ratios from 0.71021 to 0.72114, which are interpreted to reflect external radiogenic Sr, likely derived from the Paleoproterozoic strata. Some Apt III crystals have undergone extensive metasomatism indicated by abundant monazite inclusions. The metasomatized apatite has much higher Sr-87/Sr-86 ratios up to 0.73721, which is consistent with bulk-rock Rb-Sr isotope analyses of Cu ores with Sr-87/Sr-86(i) from 0.71906 to 0.74632. The elevated Sr-87/Sr-86 values of metasomatized apatite and bulk Cu ores indicate that later fluids were ... |
| نوع الوثيقة: | report |
| اللغة: | English |
| العلاقة: | MINERALIUM DEPOSITA; http://ir.gig.ac.cn/handle/344008/53725Test |
| DOI: | 10.1007/s00126-015-0578-z |
| الإتاحة: | https://doi.org/10.1007/s00126-015-0578-zTest http://ir.gig.ac.cn/handle/344008/53725Test |
| رقم الانضمام: | edsbas.83BEBFA9 |
| قاعدة البيانات: | BASE |
| DOI: | 10.1007/s00126-015-0578-z |
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