Collaborative Research: RUI: Redox Processes in Rio Grande Rift and Colorado Plateau Xenoliths

9405310 DYAR这项研究试图在严格限制的地质背景下，研究Fe3+、H+和共存的地幔矿物的主体组成之间的相互关系。样本将从里奥格兰德裂谷和科罗拉多高原地区挑选，这些地区将是计划于1995年进行的美国地质调查局多学科样带的选址。我们计划对所选地点采集的地幔包体中所有共存矿物的Fe3+/Fe比值和H+进行表征，以确定沿该断面的地幔氧化还原条件的区域变化。我们还将研究复合地幔包体中的交代氧化还原过程，重点观察隐蔽交代和显性交代之间的氧化还原异同。将测量未交代包体和复合交代包体中所有共存矿物的H+含量；如果可能，还将测定D/H比，以便更好地了解H+在地幔氧化还原过程中的作用。

9405310 Dyar This research seeks to examine the interrelationships among Fe3+, H+, and bulk composition of coexisting mantle minerals from within a carefully-constrained geologic context. Samples will be selected from Rio Grande rift and Colorado Plateau localities which will be the sites of A U.S.G.S. multidisciplinary transect planned for 1995. We plan to characterize Fe3+/ Fe ratios and H+ of all coexisting minerals in mantle xenoliths collected from the chosen localities, in order to determine regional variations in mantle redox conditions along the transect. We will also study metasomatic redox processes in composite mantle xenoliths with emphasis on observing redox differences and similarities between cryptic and patent metasomatism. H+ contents of all coexisting minerals in both unmetasomatized and composite metasomatized xenoliths will be measured; when possible, D/H ratios will also be determined in order to better understand the role of H+ in mantle redox processes.