US-France Cooperative Research: Rheology of the Transition Zone of Earth's Mantle

该奖项将支持在地球物理学的合作研究， 罗伯特·利伯曼博士，斯托尼布鲁克纽约州立大学 和地球仪物理研究所的Jean-Paul Poirier博士， 巴黎大学 本研究的目的是 更好地了解流变行为的 地幔矿物的高压相。 具体而言是 研究人员建议合成高压样品， 橄榄石和辉石相的大体积，单轴 在斯托尼布鲁克的裂球装置，并研究其 在巴黎用透射电子显微镜观察变形。 将特别关注相组合， 含有尖晶石和石榴石的混合物， 在跨越石榴石-钛铁矿相的P-T条件下 边界 这些新数据将用于解释 在地球的过渡带发生的动态过程 地幔 这些调查也与动力学有关 俯冲过程和深源的发生 岛弧区下的地震 美国和法国的实验室完全有资格追求这一点 项目 普瓦里耶博士和他的同事开发了一种技术 在高压和高温下产生共存相 在金刚石砧座装置和所用的传动装置中， 显微镜检查高压相的微观结构 在实验室合成或自然产生的陨石 冲击 位于斯托尼布鲁克的美国实验室是一个国际性的 高压测量中心。

This award will support cooperative research in geophysics between Dr. Robert Liebermann, State University of New York at Stony Brook and Dr. Jean-Paul Poirier, Institut de Physique du Globe, University of Paris VI. The objective of this research is a better understanding of the rheological behavior of the high-pressure phases of mantle minerals. Specifically, the investigators propose to synthesize specimens of high pressure phases of olivine and pyroxene in the large-volume, uniaxial split-sphere apparatus at Stony Brook and to study their deformation using tranmission electron microscopy in Paris. Special attention will be devoted to phase assemblages which contain mixtures of spinel and garnet and to specimens synthesized at P-T conditions which straddle the garnet-ilmenite phase boundary. These new data will be utilized to interpret the dynamic processes occurring in the transition zone of the Earth's mantle. These investigations also have relevance for the dynamics of the subduction processes and the occurrence of deep focus earthquakes beneath island arc regions. The U.S. and French laboratories are well qualified to pursue this project. Dr. Poirier and his colleagues have developed techniques to produce co-existing phases at high pressures and temperatures in diamond-anvil-cell apparatus and used transmission election microscopy to examine the microstructure of high pressure phases produced synthetically in the laboratory or naturally by meteorite impact. The U.S. laboratory at Stony Brook is an international center for high pressure measurement.