An Integrated Seismic and Petrologic Investigation of the Effects of Plume-Ridge Interaction on Crustal Accretion: The Galapagos Spreading Center Between 91 deg. W and 98 deg. W

羽-脊相互作用对地壳增生影响的综合地震和岩石学研究：加拉帕戈斯扩张中心在 91 度之间。

• 批准号: 9818886
• 负责人: David Graham
• 金额: $ 9.93万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-01-01 至 2002-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9818886&HistoricalAwards=false
• 关键词: Integrated; Seismic; Petrologic; Investigation; Effects

This project is a comprehensive field and laboratory program that involves coordinated seismic, petrologic and theoretical modeling studies along an 800-km-long section of the Galapagos spreading center between 91 and 98 degrees west. The objectives of the project are to: (1) determine how the compensation of the Galapagos swell is partitioned between variations in crustal thickness and mangle density by measuring crustal thickness along the swell and the degree of melting inferred from the chemistry of basalts, (2) determine if there is a threshold factor that controls the transition from an axial high to a rift valley, (3) determine how the extent of magmatic differentiation of ridge basalts relates to the presence or absence of a melt lens, and (4) determine why the degree of partial melting appears to be lower near the hotspot.

该项目是一个综合性的野外和实验室项目，涉及沿加拉帕戈斯扩张中心以西91至98度之间的800公里长的沿着协调地震、岩石学和理论建模研究。 该项目的目标是：（1）通过测量沿着隆起的地壳厚度和从玄武岩的化学性质推断的熔融程度，确定如何在地壳厚度和挤压密度的变化之间划分加拉帕戈斯隆起的补偿，（2）确定是否存在控制从轴向高压到裂谷的过渡的阈值因子，（3）确定洋脊玄武岩的岩浆分异程度与熔体透镜的存在与否的关系;（4）确定为什么在热点附近部分熔融程度似乎较低。