The Re-Os System in Mantle-Derived Rocks

本建议的目的是将Re/Os系统应用于 地幔演化中的问题和地幔岩浆源的性质 利用187 Re衰变为187 Os作为天然示踪剂。 这 研究将集中在1）比较187 Os/186 Os的比率， 洋中脊玄武岩与洋岛玄武岩; 2） 玄武岩中~（187）Os/~（186）Os和~ 3 He/~ 4 He变化的耦合应用 阐明岩浆来源; 3）系统研究了 有文献记载的中生代阿巴拉契亚拉斑玄武岩区的样品 将决定对Re和Os的控制 幔源岩浆生成演化过程中的丰度 岩石圈地幔的长期Re/Os系统学。 样品 将通过负离子热电离分析187 Os/186 Os 质谱（NTIMS）。 Re浓度将继续 由西姆斯确定。 这项工作应提供一个更广泛的 了解地幔岩浆的起源。

The objective of this proposal is to apply the Re/Os system to problems in mantle evolution and the nature of mantle magma sources using the decay of 187Re to 187Os as the natural tracer. This study will focus on 1) comparing the 187Os/186Os ratios of mid-ocean ridge basalts with those of ocean island basalts; 2) the coupled use of 187Os/186Os and 3He/4He variations in basalts elucidating magma sources; 3) a systematic study of carefully documented samples of the Mesozoic Appalachian tholeiite province of eastern North AMerica will determine the controls on Re and Os abundances during generation and evolution of mantle-derived magmas on long-term Re/Os systematics of lithosphere mantle. The samples will be analyzed for 187Os/186Os by negative ion thermal ionization mass spectrometry (NTIMS). Re concentrations will continue to be determined by SIMS. This work should provide a broader understanding of the origin of mantle magmas.