Geochemical Studies of Ocean Basin Evolution

该研究所对EPR(9o30‘N，13p30’-15oN)、MAR(36oN)、戈尔达岭、杰克逊海山总统和美国大西洋热点地区进行了重要的同位素和微量元素地球化学研究。他现在希望继续这项工作，分析太平洋和大西洋玄武岩中的微量元素丰度，目的是描述这两个扩张速度截然不同的山脊系统的来源组成和岩浆过程。此外，他将分析EPR地区的零年龄和稍老的玄武岩，以评估导致EPR沿线岩浆演化的时间地球化学变化的过程。本项目的一个重要内容是测定EPR、AMOWN和一些大洋岛国地区的大洋玄武岩的U、Th和Pb丰度。目的是研究地幔热柱与贫化的N-MORB储集层的U/Pb和Th/U比值。该项目的最终目标是量化地幔来源(羽流、枯竭的储集层)的地球化学模型以及影响大洋中脊地壳形成的过程。

The P.I. has carried out significant research on isotope and trace element geochemistry of EPR (9o30'N, 13p30'-15oN), MAR(36oN), the Gorda Ridge, President Jackson Seamounts, & S. Atlantic hot spot tracks. He now wishes to continue this effort and analyze trace element abundances in basalts from both Pacific and Atlantic oceans with the objective of characterizing source compositions and magmatic processes in the two ridge systems that have very different spreading rates. Additionally, he will analyze zero age and somewhat older basalts from the EPR area in order to evaluate the processes which cause temporal geochemical variations in magma evolution along the EPR. An important thrust of the present project is the determination of the U, Th and Pb abundances of oceanic basalts from EPR, FAMOUS, and some ocean island areas. The purpose is to characterize U/Pb and Th/U ratios of mantle plumes vs. the depleted N-MORB reservoir. The ultimate goal of this project is to quantify geochemical models of mantle sources (plumes, depleted reservoirs) and the processes which affect crust formation at mid-oceanic ridges.