H-Bearing Silicates at High Pressure: The Hydration State of the Mantle

小行星9725672 该项目将研究高压下含氢硅酸盐矿物的结构和弹性常数，以评估地幔中是否可能含有相当于水圈体积数倍的羟基形式的H2O。PI将在压力下测量压缩率并确定几种含水和名义上无水硅酸盐相的结构，包括wadsleyite，majoritic石榴石，ringwoodite，多晶白云母，硅镁石和humites。这些矿物可能是俯冲板块、上地幔和/或过渡带的含氢成分。它们的体积模量和结构在压力下的测定可以允许限制放置在可以被运送到和驻留在上地幔和过渡带的矿物中的H2O的量。

9725672 Smyth This project will investigate the structures and elastic constants of H-bearing silicate minerals at high pressure in order to assess the possibility that the mantle of Earth may contain a reservoir of H2O as hydroxyl equivalent to many times the volume of the hydrosphere. PI will measure the compressibilities and determine the structures of several hydrous and nominally anhydrous silicate phases, including wadsleyite, majoritic garnet, ringwoodite, phengitic muscovite, chlorite and humites at pressure. These minerals are likely H-bearing constituents of subducting slabs, the upper mantle and/or the transition zone. The determination of their bulk moduli and structures at pressure may allow constraints to be place on the amount of H2O that can be transported to and reside in the minerals of the upper mantle and transition zone.