Influence of water on mineralogy of the lower mantle

Ferropericlase (Fp) and bridgmanite (Brg) are the dominant minerals of the Earth’s lower mantle. Recent discoveries on the deep-water cycle demonstrate that water can be delivered to the deepest portions of the lower mantle. Even though Fp and Brg have been intensively investigated over the last decades, our current knowledge on high-pressure (HP)-high-temperature (HT) reactions of Fp and Brg with water is very limited. In order to provide a comprehensive picture on Fp-H2O and Brg-H2O interactions at HP-HT conditions of the lower mantle, we propose to perform multi-methodological studies employing both in situ powder and single-crystal X-ray diffraction (XRD) and in situ Synchrotron Mössbauer Source (SMS).

铁方镁石（Ferropericlase，Fp）与布里奇曼石（bridgmanite，Brg）是地球下地幔的主要矿物。近年来有关深部水循环的研究表明，水可被输送至下地幔的最深区域。尽管近几十年来学界对铁方镁石和布里奇曼石已开展了大量深入研究，但目前我们对二者在高压（HP）-高温（HT）条件下与水发生的反应的认知仍极为有限。为全面阐明下地幔高压高温环境中铁方镁石-水与布里奇曼石-水的相互作用规律，本研究拟采用原位粉末与单晶X射线衍射（XRD）以及原位同步穆斯堡尔源（SMS）等多方法学实验手段。