Petrology and Geochemistry of Spinel-Peridotite Xenoliths from Central Mexico: Mantle Domains and Processes

在与一位墨西哥同事的合作下， 综合地质学、岩石学和地球化学研究， 中新世至近代火山岩， 墨西哥中部最南端的盆地山脉省。 计划通过以下方式将这项工作扩展到样带区域： 进行全面的岩石学和地球化学研究， 幔源尖晶石二辉橄榄岩捕虏体 主元 对整个岩石样品和组成矿物的分析将 使PI能够评估捕虏体的岩石成因模型 作为肥沃的橄榄岩地幔部分熔融的残留物， 为了评估上地幔成分的区域差异， 温度、氧逸度和熔体萃取程度。 他们还计划对Sr-Nd-Pb同位素进行详细研究 比值和微量元素丰度的单斜辉石，这将 使他们能够研究复杂的 上地幔流体/熔体地球化学，如 与第三纪俯冲事件有关，与 岩石圈伸展

In collaboration with a Mexican colleague the PIs are conducting an integrated geological, petrological, and geochemical study of Miocene to Recent volcanic rocks from a transect across the southernmost Basin and Range Province (BRP) of central Mexico. The plan is to extend this work in the transect area by conducting a comprehensive petrological and geochemical study of mantle-derived spinel-lherzolite xenoliths. Major-element analyses of whole-rock samples and constituent minerals will enable the PIs to evaluate petrogenetic models for the xenoliths as residues of partial melting of fertile peridotitic mantle and to evaluate regional differences in upper-mantle composition, temperature, oxygen fugacity, and degree of melt extraction. They also plan to conduct detailed studies of Sr-Nd-Pb isotopic ratios and trace-element abundances in clinopyroxenes, which will allow them to investigate complex metasomatic modifications of the upper-mantle geochemistry by fluid/melts, such as those related to the Tertiary subduction event and those related to on- going lithospheric extension.