...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Contributions to Mineralogy and Petrology >Ti K-edge XANES study on the coordination number and oxidation state of Titanium in pyroxene, olivine, armalcolite, ilmenite, and silicate glass during mare basalt petrogenesis
【24h】

Ti K-edge XANES study on the coordination number and oxidation state of Titanium in pyroxene, olivine, armalcolite, ilmenite, and silicate glass during mare basalt petrogenesis

机译：Ti K-Edge Xanes在Mare玄武岩培养基中纤维素，橄榄石，甲硫酸盐，钛铁矿和硅酸盐玻璃配位数量和氧化状态研究

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Lunar mare basalts are a product of partial melting of the lunar mantle under more reducing conditions when compared to those expected for the Earth's upper mantle. Alongside Fe, Ti can be a major redox sensitive element in lunar magmas, and it can be enriched by up to a factor of ten in lunar basaltic glasses when compared to their terrestrial counterparts. Therefore, to better constrain the oxidation state of Ti and its coordination chemistry during lunar magmatic processes, we report new X-ray absorption near edge structure (XANES) spectroscopy measurements for a wide range of minerals (pyroxene, olivine, Fe-Ti oxides) and basaltic melt compositions involved in partial melting of the lunar mantle. Experiments were conducted in 1bar gas-mixing furnaces at temperatures between 1100 and 1300 degrees C and oxygen fugacities (fO(2)) that ranged from air to two orders of magnitude below the Fe-FeO redox equilibrium. Run products were analysed via electron microprobe and XANES Ti K-edge. Typical run products had large (100 mu m) crystals in equilibrium with quenched silicate glass. Ti K-edge XANES spectra show a clear shift in energy of the absorption edge features from oxidizing to reducing conditions and yield an average valence for Fe-Ti oxides (armalcolite and ilmenite) of 3.6, i.e., a 40% of the overall Ti is Ti3+ under fO(2) conditions relevant to lunar magmatism (IW -1.5 to -1.8). Pyroxenes and olivine have average Ti valence of 3.75 (i.e., 25% of the overall Ti is trivalent), while in silicate glasses Ti is exclusively tetravalent. Pre-edge peak intensities also indicate that the coordination number of Ti varies from an average V-fold in silicate glass to VI-fold in the Fe-Ti oxides and a mixture between IV and VI-fold coordination in the pyroxenes and olivine, with up to 82% Ti-[IV](4+) in the pyroxene. In addition, our results can help to better constrain the Ti3+/Sigma Ti of the lunar mantle phases during magmatic processes and are applied to provide first insights into the mechanisms that may control Ti mass-dependent equilibrium isotope fractionation in lunar mare basalts.
机译：与地球上部地幔的预期相比，月球Mare Basalts是在更加缩小的条件下偏离月球地幔的份量。与Fe一起，TI可以是农历岩浆中的主要氧化还原敏感元素，与其地面对应物相比，它可以在月球玄武岩眼镜中富于10倍。因此，为了更好地限制Ti的氧化状态及其在农历岩岩过程中的协调化学，我们在宽范围的矿物（辉石，橄榄石，Fe-Ti氧化物）中报告了近边缘结构（XANES）光谱测量的新X射线吸收。和玄武岩熔体组合物涉及月球地幔的部分熔化。在1Bar气体混合炉中在1100-1300℃的温度下进行实验，氧气逃逸条件（FO（2）），其范围为Fe-Feo氧化还原平衡下的两个数量级。通过电子微探针和Xanes Ti K-Edge分析运行产品。典型的运行产品具有大（＆100μm）晶体中的晶体，硅酸盐玻璃淬灭。 Ti K-Edge Xanes Spectra显示出吸收边缘特征的能量清晰的偏移，从氧化到还原条件，并产生3.6的Fe-Ti氧化物（Armalcolite和Ilmenite）的平均值，即，整体Ti的40％是TI3 +下的FO（2）条件与月球岩岩（IW -1.5至-1.8）相关。焦仙和橄榄石的平均Ti值为3.75（即总整体Ti的25％是三价），而在硅酸盐眼镜中，Ti专门是四价的。预先预先峰值强度还表明Ti的配位数量从硅酸盐玻璃中的平均V折叠变化至Fe-Ti氧化物中的VI倍，并且在冰甲烯和橄榄石中的IV和VI折叠配位之间的混合物在辉石中高达82％的Ti-[IV]（4+）。此外，我们的结果可以有助于在岩石过程中更好地限制月球地幔阶段的Ti3 + / Sigma Ti，并应用于对可能控制月球母马沼气中的Ti质量依赖性同位素分级的机制提供第一洞察力。

著录项

  • 来源
  • 作者

    Leitzke F. P.; Fonseca R. O. C.; Goettlicher J.; Steininger R.; Jahn S.; Prescher C.; Lagos M.;

  • 作者单位

    Rheinische Friedrich Wilhelms Univ Bonn Steinmann Inst Geol Mineral &

    Palaontol Poppelsdorfer Schloss Mineral Museum D-53115 Bonn Germany;

    Rheinische Friedrich Wilhelms Univ Bonn Steinmann Inst Geol Mineral &

    Palaontol Poppelsdorfer Schloss Mineral Museum D-53115 Bonn Germany;

    Karlsruhe Inst Technol Inst Photon Sci &

    Synchrotron Radiat D-76021 Karlsruhe Germany;

    Karlsruhe Inst Technol Inst Photon Sci &

    Synchrotron Radiat D-76021 Karlsruhe Germany;

    Univ Cologne Inst Geol &

    Mineral D-50674 Cologne Germany;

    Univ Cologne Inst Geol &

    Mineral D-50674 Cologne Germany;

    Rheinische Friedrich Wilhelms Univ Bonn Steinmann Inst Geol Mineral &

    Palaontol Poppelsdorfer Schloss Mineral Museum D-53115 Bonn Germany;

  • 收录信息
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 矿物学;岩石学;
  • 关键词

    Mantle; Experimental petrology; XANES; Mare basalts; Moon;

    机译：披风;实验岩石学;Xanes;母马玄武岩;月亮;

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号