Os Isotopic Studies of Solid Earth Evolution

9804875Carlson该提案要求一个基于成就的更新，以继续支持我们将Re-Os同位素系统应用于固体地球地球化学演化问题。我们将重点关注：1)描述了基性成分（辉石岩、榴辉岩）在意大利洋中脊玄武岩地幔源和基性钾质火山作用中的重要性；3)将克拉通地幔橄榄岩捕虏体的Re-Os系统研究扩展到中国和西非地区。4)对巴西米纳斯吉拉斯州下地壳石榴石麻粒岩捕虏体的Re-Os系统进行研究，确定该地区地壳形成的年代学。5)研究了中国东部大别、苏鲁地系榴辉岩和橄榄岩的Re-Os体系，确定了这些物质的火成岩形成年代，并考察了Re、Os在高变质作用中的表现。6)利用同位素稀释ICP-MS测量了大部分样品中铂族元素在火成岩分异过程中的表现，提高了对铂族元素在火成岩分异过程中的表现的认识。

9804875Carlson This proposal requests an Accomplishment Based Renewal for continued support of our application of the Re-Os isotope system to problems concerning the geochemical evolution of the solid Earth. We will focus on: 1) Delineation of the importance of mafic components (pyroxenites, eclogites) in the mantle sources of mid-ocean ridge basalts and mafic-potassic volcanism from Italy, the Colorado Plateau and southwestern Africa. 2) Re-Os age dating of sulfide inclusions in diamonds from the Slave craton and N.W. Australia. 3) Extend our studies of the Re-Os systematics of cratonic mantle peridotite xenoliths to China and west Africa. 4) Examine the Re-Os systematics of lower crustal garnet granulite xenoliths from Minas Gerais, Brazil to define the chronology of crust formation in this area. 5) Study the Re-Os system of the eclogitic and peridotitic rocks of the Dabie and Su-Lu terranes in eastern China to date the igneous formation of these materials and to examine the behavior of Re and Os during high-grade metamorphism. 6) Improve the understanding of the behavior of the platinum group elements (PGE's) during igneous differentiation by measuring whole rock PGE patterns by isotope dilution ICP-MS in most of the samples studied for Re-Os isotopic variation.