Seismic and Petrologic Investigation of the Effects of Plume-Ridge Interaction at the Galapagos Spreading Center

加拉帕戈斯扩张中心羽流-山脊相互作用影响的地震和岩石学研究

• 批准号: 0000478
• 负责人: Jacqueline Dixon
• 金额: $ 5.19万
• 依托单位: University of Miami
• 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: 2000-02-01 至 2003-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0000478&HistoricalAwards=false
• 关键词: Seismic; Petrologic; Investigation; Effects; Plume

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现场和实验室项目，涉及沿加拉帕戈斯扩张中心西经 91 度至 98 度之间 800 公里长的一段协调地震、岩石学和理论建模研究。 该项目的目标是：(1) 通过测量沿隆起的地壳厚度以及从玄武岩化学推断的熔融程度，确定加拉帕戈斯隆起的补偿如何在地壳厚度和破碎密度的变化之间分配，(2 ）确定是否存在控制从轴向高地到裂谷过渡的阈值因素，（3）确定山脊玄武岩的岩浆分异程度与是否存在熔化透镜，以及 (4) 确定为什么热点附近部分熔化的程度似乎较低。