Earth Sciences Postdoctoral Research Fellowship Award

地球科学博士后研究奖学金

• 批准号: 9505215
• 负责人: John Lassiter
• 金额: $ 7.2万
• 依托单位: Fellowships
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-06-01 至 1999-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9505215&HistoricalAwards=false
• 关键词: Earth; Sciences; Postdoctoral; Research; Fellowship

EAR-9505215 Lassiter, John C. Re-Os isotopic data from a suite of cogenetic basalts from Hawaii will be used to improve understanding of the behavior of Re and Os during melting of the mantle and melt transport through the crust. Because of the analytical difficulties in measuring Re and Os abundances in very low-concentration materials, it is only in the past few years that it has been possible to consider application of Re-Os systematics to problems of mantle convection and crustal evolution. Unlike other isotopic systems currently used to address these fundamental problems, Os behaves compatibly during melting. As a result, 187Os/186Os ratios are extremely sensitive to relative contributions of evolved and primitive materials. This project will (1) constrain the chemical behavior of Os (and Re) during melt production; (2) document the interaction of melts with the surrounding mantle and crust during transport to the surface; and (3) determine the degree of Os isotopic heterogeneity in the basalts and the relationship to possible mantle heterogeneities. These advances in the understanding of Re-Os systematics will permit their use in advancing the overall understanding of mantle evolution.

Lassiter，John C. 来自夏威夷的一套同生玄武岩的铼-锇同位素数据将被用来提高对地幔熔融和熔体通过地壳输送过程中铼和锇行为的认识。 由于在测量非常低浓度的材料中Re和Os丰度的分析困难，仅在过去几年中，才有可能考虑将Re-Os系统学应用于地幔对流和地壳演化问题。 与目前用于解决这些基本问题的其他同位素系统不同，Os在熔化过程中表现出相容性。 因此，187 Os/186 Os比值对演化和原始物质的相对贡献非常敏感。 该项目将（1）限制熔融生产过程中Os（和Re）的化学行为;（2）记录熔融物在向地表输送过程中与周围地幔和地壳的相互作用;（3）确定玄武岩中Os同位素不均匀性的程度以及与可能的地幔不均匀性的关系。 这些进展，在了解Re-Os系统学将允许他们在推进地幔演化的整体理解的使用。