Experimental Petrology of the Lower Mantle

下地幔实验岩石学

• 批准号: 8903801
• 负责人: Raymond Jeanloz
• 金额: $ 11.9万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-08-01 至 1992-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8903801&HistoricalAwards=false
• 关键词: Experimental; Petrology; Lower; Mantle

This proposal describes a 2-year program to experimentally investigate the petrology of the lower mantle, the single largest region of the earth. Using the laser-heated diamond cell, a natural garnet peridotite composition will be taken to P-T conditions existing throughout the lower mantle . A combination of in situ X-ray diffraction and quenched-product analysis will be used to determine: (1) the identity and quantity of major phases present; (2) the major-element partitioning between these phases as a function of pressure; (3) the equations of state of the phases, and hence of the assemblage for direct comparison with the seismological profiles of the lower mantle; and (4) the solidus temperature of the assemblage from which tight constraints on the deep-mantle geotherm could be obtained. Year 1 will concentrate on sub-solidus equilibria, and Year 2 will concentrate on solidus/liquidus equilibria of the natural peridotite composition as well as reconnaissance (solid-state and liquid) equilibria of an iron-enriched composition. These experiments are a direct extension of techniques used in prior work that successfully determined the ultrahigh P/T equilibria of individual natural minerals, and they would represent the first time that an actual rock assemblage had been studied at the conditions existing throughout the bulk of the mantle.

该提案描述了一个为期2年的计划， 研究下地幔的岩石学， 地球的区域。 使用激光加热金刚石细胞， 天然石榴石橄榄岩成分将采取P-T 整个下地幔都存在的条件。 的组合 现场X射线衍射和淬火产物分析将 用于确定：（1）主要的身份和数量 （2）主要元素之间的分配 相作为压力的函数;（3）状态方程， 相，因此，集合的直接比较 与下地幔地震剖面的关系;（4） 组合的固相线温度， 可以得到对深地幔地热的约束。 年 第一年将专注于亚固相线平衡，第二年将 专注于自然界的固液平衡 橄榄岩成分以及普查（固态和 液体）平衡。 这些 实验是现有技术中使用的技术的直接延伸。 这项工作成功地确定了 单独的天然矿物，它们代表了第一个 当时，一个实际的岩石组合已被研究， 存在于整个地幔中的条件。