Academic Journal
Adrianite, Caâ‚â‚‚(Alâ‚„Mg₃Si₇)O₃₂Cl₆, a new Cl-rich silicate mineral from the Allende meteorite: An alteration phase in a Ca-Al-rich inclusion
| العنوان: | Adrianite, Caâ‚â‚‚(Alâ‚„Mg₃Si₇)O₃₂Cl₆, a new Cl-rich silicate mineral from the Allende meteorite: An alteration phase in a Ca-Al-rich inclusion |
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| المؤلفون: | Ma, Chi, Krot, Alexander N. |
| المصدر: | American Mineralogist, 103(8), 1329-1334, (2018-08-01) |
| بيانات النشر: | Mineralogical Society of America |
| سنة النشر: | 2018 |
| المجموعة: | Caltech Authors (California Institute of Technology) |
| مصطلحات موضوعية: | Adrianite, Ca_(12)(Al_4Mg_3Si_7)O_(32)Cl_6, new mineral, wadalite group, alteration mineral, Ca-Al-rich inclusion, Allende meteorite, carbonaceous chondrite |
| الوصف: | Adrianite (IMA 2014-028), Caâ‚â‚‚(Alâ‚„Mg₃Si₇)O₃₂Cl₆,, is a new Cl-rich silicate mineral and the Si,Mg analog of wadalite. It occurs with monticellite, grossular, wadalite, and hutcheonite in altered areas along some veins between primary melilite, spinel, and Ti,Al-diopside in a Type B1 FUN (Fractionation and Unidentified Nuclear effects) Ca-Al-rich inclusion (CAI), Egg-3, from the Allende CV3 carbonaceous chondrite. The mean chemical composition of type adrianite by electron probe microanalysis is (wt%) CaO 41.5, SiOâ‚‚ 27.5, Alâ‚‚O₃ 12.4, MgO 7.3, Naâ‚‚O 0.41, Cl 13.0, O=Cl –2.94, total 99.2, giving rise to an empirical formula of (Ca_(11.69)Na_(0.21))(Al_(3.85)Mg_(2.88)Si_(7.23))O₃₂Cl_(5.80). The end-member formula is Caâ‚â‚‚(Mgâ‚…Si₉)O₃₂Cl₆. Adrianite has the I43d wadalite structure with a = 11.981 Ã…, V = 1719.8 ų, and Z = 2, as revealed by electron backscatter diffraction. The calculated density using the measured composition is 3.03 g/cm³ Adrianite is a new secondary mineral in Allende, apparently formed by alkali-halogen metasomatic alteration of primary CAI minerals such as melilite, anorthite, perovskite, and Ti,Al-diopside on the CV chondrite parent asteroid. Formation of secondary Cl-rich minerals sodalite, adrianite, and wadalite during metasomatic alteration of the Allende CAIs suggests that the metasomatic fluids had Cl-rich compositions. The mineral name is in honor of Adrian J. Brearley, mineralogist at the University of New Mexico, U.S.A., in recognition of his many contributions to the understanding of secondary mineralization in chondritic meteorites. ; © 2018 Mineralogical Society of America. Manuscript received February 12, 2018; Manuscript accepted May 4, 2018; Manuscript handled by Steve Simon. SEM, EBSD, and EPMA were carried out at the Geological and Planetary Science Division Analytical Facility, Caltech, which is supported in part by NSF grants EAR-0318518 and DMR-0080065. This work was also supported by NASA grant NNX12AJ01G. We thank Mike Zolensky, ... |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | unknown |
| Relation: | https://www.ncbi.nlm.nih.gov/pmc/PMC6448150; eprintid:88416 |
| DOI: | 10.2138/am-2018-6505 |
| الاتاحة: | https://doi.org/10.2138/am-2018-6505 https://www.ncbi.nlm.nih.gov/pmc/PMC6448150 |
| Rights: | info:eu-repo/semantics/openAccess ; Other |
| رقم الانضمام: | edsbas.A70EC65F |
| قاعدة البيانات: | BASE |
| DOI: | 10.2138/am-2018-6505 |
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