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

利用深渊橄榄岩、辉长岩和玄武岩中的氦和氩同位素研究大洋中脊下的上地幔异质性和部分熔融

• 批准号: 0850666
• 负责人: David Graham
• 金额: $ 32.39万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-05-15 至 2013-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0850666&HistoricalAwards=false
• 关键词: Investigating; Upper; Mantle; Heterogeneity; Partial

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.

这项研究研究了海洋岩石中稀有气体的同位素变化，并产生了对地幔化学结构、岩浆部分熔融过程以及涉及洋壳演化和变质作用的流体起源等争论具有重要意义的数据。 对稀有气体（He、Ar）和 CO2 的分析将是对海底橄榄岩和辉长岩的首次分析。 数据将用于检查上地幔化学和同位素异质性的长度尺度。 样本来自三个区域：大西洋中脊（ODP Leg 209）、凯恩海洋核心复合体和北冰洋超慢速扩张的加克尔海脊。所有样品均已针对其他重要的地球化学参数进行了良好的分析表征。 这项工作的更广泛影响包括通过支持俄勒冈州立大学由国家科学基金会资助的新稀有气体设施来建设科学基础设施。 研究生和本科生将从事研究，项目成果将纳入地球化学研究生水平课程的教学计划中。 结果将发布在网络上。