Investigating Upper Mantle Heterogeneity and Partial Melting Beneath Mid-Ocean Ridges Using Helium and Argon Isotopes in Abyssal Peridotite, Gabbro and Basalt

这项研究考察了海洋岩石中稀有气体的同位素变化，并产生了一些数据，这些数据对地球地幔的化学结构、岩浆的部分熔融过程以及参与洋壳演化和变质作用的流体的起源的争论具有重要意义。对惰性气体(He、Ar)和二氧化碳的分析将是对海底橄榄岩和辉长岩进行的首批分析之一。数据将被用来检查上地幔化学和同位素不均一性的长度尺度。样品来自三个地区：大西洋中部海脊(ODP209段)、凯恩海洋核心杂岩和北冰洋超缓慢扩张的Gakkel海脊。所有样品都已经对其他重要的地球化学参数进行了很好的分析表征。这项工作的更广泛影响包括通过支持俄勒冈州立大学NSF资助的新的稀有气体设施为科学建设基础设施。研究生和本科生将从事研究，项目成果将纳入研究生水平的地球化学班的教学计划。结果将在网上公布。

This research examines the isotopic variations of noble gases in oceanic rocks and produces data that bear significantly on debates about the chemical structure of Earth's mantle, partial melting processes of magmas, and the origin of fluids involved in ocean crust evolution and metamorphism. Analyses of noble gases (He, Ar) and CO2 will be some of the first made for seafloor peridotites and gabbros. Data will be used to examine the length scales of chemical and isotopic heterogeneity in the upper mantle. Samples come from three areas: the Mid-Atlantic Ridge (ODP Leg 209), the Kane oceanic core complex, and the ultra-slow spreading Gakkel Ridge in the Arctic Ocean. All samples have already been well characterized analytically for other important geochemical parameters. Broader impacts of the work include building infrastructure for science through support of the new NSF-funded Noble Gas Facility at Oregon State University. Graduate and undergraduate students will be engaged in research and project results will be incorporated into instructional programs of graduate level classes in geochemistry. Results will be posted on the web.