• 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 >Experimentally determined stability of alkali amphibole in metasomatised dunite at sub-arc pressures
【24h】

Experimentally determined stability of alkali amphibole in metasomatised dunite at sub-arc pressures

机译：在亚弧压力下甲状腺肿型DINE中碱倒数的实验确定稳定性

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

The phase and melting relationships of olivine mixed with 25 % of hydrous felsic slab melt have been determined in piston-cylinder experiments between 2.5 and 4.5 GPa and 800 to 1,050 degrees C to constrain metasomatic processes in the mantle wedge above subduction zones. At sub-solidus conditions, olivine, orthopyroxene, phlogopite, a Na-rich amphibole and an aqueous fluid are present. Na-rich amphibole is still observed at 950 degrees C at 4.5 GPa, providing evidence that this hydrous phase might be stable at sub-arc depths in an alkali-rich, Ca-poor mantle wedge. The maximum temperature stability is reached at 1,000 degrees C at 3.5 GPa, where amphibole coexists with hydrous melt. A sodium-rich phlogopite is stable over the whole range of P-T conditions investigated. At 2.5 GPa, 850 degrees C, aspidolite (Na analogue of phlogopite) has been observed as a sodium-bearing phase in the peridotite. The wet solidus in the metasomatised dunite lies between 850 and 900 degrees C at 2.5 GPa and between 950 and 975 degrees C at 3.5 GPa. At 4.5 GPa, melting relations are ambiguous and no clear solidus was found. The consumption of amphibole and minor phlogopite at the wet solidus produced Na- and H2O-rich phonolitic melts. The presence of phlogopite and sodic amphibole in the metasomatised dunite has implications on alkali and water storage in the part of the mantle wedge that is coupled to the down-going slab and might play a role on alkali and trace element recycling through arc magmatism.
机译：在2.5和4.5GPa和800至1,050℃之间的活塞 - 圆柱实验中确定了与25％的含水铰链板熔体混合的橄榄石的相和熔化关系，以约束在俯冲区域上方的地幔楔中的态化过程。在亚固体条件下，存在橄榄石，垂直烯，植物，富含Na富含的倒置和水性流体。富含Na的倒置仍然在950摄氏度下观察到4.5GPa，提供了这种含水相的含量在含碱的Ca-Pand Mantle Wedge中的亚弧深度稳定。在3.5GPa的3.5GPa下，最大温度稳定性在3.5GPa达到3.5℃，其中倒角与含水熔体共存。富含钠的磷酸钠在研究的整个P-T条件下稳定。在2.5GPa，850℃，已经观察到恒星岩石中的钠均钠阶段的850℃，Aspidolite（Na类似物）。脱脂的DINE中的湿固体在850至900摄氏度之间，在2.5GPa和950至975摄氏度之间，在3.5GPa之间。在4.5GPa，熔化关系是含糊不清的，没有发现明确的固体。在湿固体中消耗锥体和次要磷酸盐产生Na-和H 2 O的发音熔体。在甲状腺肿的DINE中存在吡吡盐和钠倒数的存在对碱和水储存的含量覆盖的储水在与下降板上相连，并且可能在通过弧形岩浆中的碱和痕量元素回收的作用。

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