Uvarovite from Reduced Native Fe-Bearing Paralava, Hatrurim Complex, Israel

IF 1.8 4区 地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS
Jacek Futrzyński, Rafał Juroszek, Katarzyna Skrzyńska, Yevgeny Vapnik, Evgeny Galuskin
{"title":"Uvarovite from Reduced Native Fe-Bearing Paralava, Hatrurim Complex, Israel","authors":"Jacek Futrzyński, Rafał Juroszek, Katarzyna Skrzyńska, Yevgeny Vapnik, Evgeny Galuskin","doi":"10.2113/2023/lithosphere_2023_214","DOIUrl":null,"url":null,"abstract":"Abstract A new genetic type of chromium garnet—uvarovite with the simplified formula Ca3(Cr,Al,Ti4+,V3+)2(Si,Al)3O12—was detected in unusual wollastonite-gehlenite-bearing paralava within the Hatrurim Complex in Israel. The pyrometamorphic rocks of that Complex usually formed in the sanidinite facies (low pressure and high temperature) and, as a rule, under oxidized conditions. This paralava contains nodules and grain aggregates of native Fe, usually distributed linearly in the rock or located close to gaseous voids. The presence of native iron droplets in association with the “meteoric” phosphide—schreibersite, suggests that the formation of paralava occurred under high-reducing conditions and high temperature, reaching 1500°C. Uvarovite forms xenomorphic grains either randomly distributed within the rock or flattened crystals on the walls of gaseous voids. Analyzed uvarovite indicates a significant enrichment in Ti4+ (up to 8 wt.% TiO2) and V3+ (up to 4.5 wt.% V2O3), the highest concentrations documented for uvarovite. Unlike known uvarovite from different localities, uvarovite from this study does not contain Fe3+, and Fe2+ is present in insignificant amounts. The obtained structural data reveal that the high contribution of hutcheonite, Ca3Ti4+2SiAl2O12 (up to 18%), and goldmanite, Ca3V3+2Si3O12 (up to 11%), end-members increases the lattice parameter a to >12.00 Å. The crystallization of uvarovite occurs in the narrow interval of oxygen fugacity, a little above the iron-wüstite buffer ƒO2 ≥ ΔIW. Uvarovite xenomorphic grains formed due to the decomposition of wollastonite and chromite, including H2S from the intergranular melt/fluid according to the following reaction: Ca3Si3O9 + Fe2+Cr3+2O4 + H2S → Ca3Cr2Si3O12 + FeS + H2O, while the flattened crystals grew from specific melt that formed on the walls of the voids as a result of exposure of hot gas flow. The comparison of the obtained results with available chemical data from previous studies reveals a gap in the natural isomorphic series between andradite and uvarovite.","PeriodicalId":18147,"journal":{"name":"Lithosphere","volume":null,"pages":null},"PeriodicalIF":1.8000,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Lithosphere","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.2113/2023/lithosphere_2023_214","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GEOCHEMISTRY & GEOPHYSICS","Score":null,"Total":0}
引用次数: 0

Abstract

Abstract A new genetic type of chromium garnet—uvarovite with the simplified formula Ca3(Cr,Al,Ti4+,V3+)2(Si,Al)3O12—was detected in unusual wollastonite-gehlenite-bearing paralava within the Hatrurim Complex in Israel. The pyrometamorphic rocks of that Complex usually formed in the sanidinite facies (low pressure and high temperature) and, as a rule, under oxidized conditions. This paralava contains nodules and grain aggregates of native Fe, usually distributed linearly in the rock or located close to gaseous voids. The presence of native iron droplets in association with the “meteoric” phosphide—schreibersite, suggests that the formation of paralava occurred under high-reducing conditions and high temperature, reaching 1500°C. Uvarovite forms xenomorphic grains either randomly distributed within the rock or flattened crystals on the walls of gaseous voids. Analyzed uvarovite indicates a significant enrichment in Ti4+ (up to 8 wt.% TiO2) and V3+ (up to 4.5 wt.% V2O3), the highest concentrations documented for uvarovite. Unlike known uvarovite from different localities, uvarovite from this study does not contain Fe3+, and Fe2+ is present in insignificant amounts. The obtained structural data reveal that the high contribution of hutcheonite, Ca3Ti4+2SiAl2O12 (up to 18%), and goldmanite, Ca3V3+2Si3O12 (up to 11%), end-members increases the lattice parameter a to >12.00 Å. The crystallization of uvarovite occurs in the narrow interval of oxygen fugacity, a little above the iron-wüstite buffer ƒO2 ≥ ΔIW. Uvarovite xenomorphic grains formed due to the decomposition of wollastonite and chromite, including H2S from the intergranular melt/fluid according to the following reaction: Ca3Si3O9 + Fe2+Cr3+2O4 + H2S → Ca3Cr2Si3O12 + FeS + H2O, while the flattened crystals grew from specific melt that formed on the walls of the voids as a result of exposure of hot gas flow. The comparison of the obtained results with available chemical data from previous studies reveals a gap in the natural isomorphic series between andradite and uvarovite.
以色列Hatrurim杂岩中原生原生含铁岩的还原乌瓦云母
摘要在以色列Hatrurim杂岩中发现了一种新的含铬石榴石-绿榴石成因类型,其简化式为Ca3(Cr,Al,Ti4+,V3+)2(Si,Al) 3o12。该杂岩的热变质岩通常形成于砂质岩相(低压高温),通常在氧化条件下形成。这种副矿岩含有原生铁的结核和颗粒聚集体,通常在岩石中呈线性分布或靠近气态空洞。与“陨星”磷化-晶伯体相关的天然铁滴的存在表明,副洼的形成发生在高还原条件和高温下,达到1500℃。玉云母形成异型颗粒,或随机分布在岩石中,或在气体空洞壁上形成扁平晶体。分析表明,乌瓦云母中Ti4+(高达8 wt.% TiO2)和V3+(高达4.5 wt.% V2O3)含量显著富集,这是乌瓦云母中记录的最高浓度。与来自不同地区的已知uvaroite不同,本研究的uvaroite不含Fe3+, Fe2+的含量也很低。得到的结构数据表明,hutcheonite Ca3Ti4+2SiAl2O12(高达18%)和goldmanite Ca3V3+2Si3O12(高达11%)的高贡献使晶格参数a增加到>12.00 Å。uvaroite的结晶发生在氧逸度的狭窄区间,略高于铁- wstite缓冲液ƒO2≥ΔIW。硅灰石和铬铁矿分解后,晶间熔体/流体产生H2S,其中H2S由Ca3Si3O9 + Fe2+Cr3+2O4 + H2S→Ca3Cr2Si3O12 + FeS + H2O反应形成,而扁平晶体则是由于热气流暴露在孔洞壁上形成的特定熔体形成的。将所得结果与已有的化学资料进行比较,发现安长石与乌云母在天然同构序列上存在差距。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Lithosphere
Lithosphere GEOCHEMISTRY & GEOPHYSICS-GEOLOGY
CiteScore
3.80
自引率
16.70%
发文量
284
审稿时长
>12 weeks
期刊介绍: The open access journal will have an expanded scope covering research in all areas of earth, planetary, and environmental sciences, providing a unique publishing choice for authors in the geoscience community.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信