...
  • 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 >The effect of solid solution on the stability of talc and 10-angstrom phase
【24h】

The effect of solid solution on the stability of talc and 10-angstrom phase

机译：固体溶液对滑石和10埃相稳定性的影响

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

Talc and 10-angstrom phase are hydrous phases that are implicated in fluid processes and rheological behaviour in subduction zones. Natural samples of talc show limited compositional variation away from the MgO-SiO2-H2O (MSH) endmember, with only substitution of Fe2+ for Mg occurring in significant amounts. In experiments at 2 GPa, talc containing 0.48 apfu Fe2+ begins to break down in the divariant field talc + anthophyllite + quartz at similar to 550 degrees C, a temperature similar to 270 degrees C lower than in the MSH system. At 4 GPa, Fe-bearing talc breaks down over a wide temperature interval in the divariant field talc + enstatite + coesite. The large decrease in temperature of the beginning of talc breakdown shows that Fe2+ is partitioned strongly into enstatite and anthophyllite with respect to talc. In phase reversal experiments at 6.5 GPa, the beginning of the dehydration of 10-angstrom phase containing 0.48 apfu Fe2+ was bracketed between 575 degrees C and 600 degrees C, a temperature similar to 100 degrees C lower than the MSH endmember reaction. The relative positions of the talc and 10-angstrom phase dehydration reactions indicate that the latter is able to accommodate greater Fe substitution, and is, therefore, more stable in Fe-bearing systems. In experiments at 6.2 GPa, 650 degrees C in the systems MgO-Al2O3-SiO2-H2O (MASH) and Na2O-MgO-Al2O3-SiO2-H2O (NMASH), 10-angstrom phase was synthesised that contains up to 0.5 apfu Al in the system MASH (compared to 0.8 in the starting material) and up to 0.4 apfu Al + 0.4 apfu Na in the system NMASH (compared to 0.7 of each of Al and Na in the starting material). Further experiments are required to determine if higher Al and Na contents in 10-angstrom phase are possible. The much higher Al and Na contents than found in talc indicate that, as with Fe, substitution of these elements enlarges the 10-angstrom phase stability field with respect to talc. In contrast to the effect of Fe, Al and Na also increase the stability of 10-angstrom phase relative to its thermal breakdown products enstatite + coesite.
机译：滑石和10埃相的相是含水相，其涉及俯冲区域的流体方法和流变行为。滑石的天然样品显示出远离MgO-SiO2-H2O（MSH）端部的有限的组成变化，只有Fe2 +的替代物，Mg的成分为显着量。在2GPa的实验中，含有0.48 APFU Fe2 +的滑石开始分解为类似于550℃的Divariant Field Talc + Anthophyllite +石英，温度比MSH系统低270℃。在4 GPA，Fe-ubian Talc在Divaliant Field Talc + Enstatite + Coesite中突破一个宽的温度间隔。滑石击穿开始的大的降低表明Fe2 +强烈地分配到山牙酸盐和接触的滑石中。在6.5GPa的相逆转实验中，含有0.48 APFU Fe2 +的10-angstrom相的脱水开始在575℃和600℃之间，温度比MSH Endmemense反应低100℃。滑石和10埃相脱水反应的相对位置表明，后者能够适应更大的Fe替换，因此在Fe承载系统中更稳定。在6.2GPa的实验中，在系统MgO-Al 2 O 3-SiO 2-H 2 O（MASH）和Na 2 O-MgO-Al 2 O 3-SiO 2-H 2 O（NMASH）中，合成10-Angstrom相，其中含有高达0.5 APFU AL系统醪（在起始材料中的0.8相比）和在系统NMASH中最高可达0.4 APFU Al + 0.4 APFU Na（与原料中的每一个和Na中的0.7相比）。需要进一步的实验来确定10-angstrom相位中的较高的Al和Na含量是可能的。在滑石中发现的高得多的Al和Na含量表明，与Fe一样，这些元素的取代相对于滑石来扩大10埃相相稳定性场。与Fe，Al和Na的作用相比，还增加了10-Angstrom相对于其热分解产物enstatite +聚酯的稳定性。

著录项

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