Collaborative Research: A Magnetotelluric Study of the Lower Crust and Upper Mantle in California

合作研究：加利福尼亚州下地壳和上地幔的大地电磁研究

• 批准号: 8817149
• 负责人: Theodore Madden
• 金额: --
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-01-01 至 1990-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8817149&HistoricalAwards=false
• 关键词: Collaborative; Research; Magnetotelluric; Study; Lower

This is a collaborative project for making magnetotelluric measurements and three dimensional interpretations in California that will concentrate on determining the lower crust and upper mantle resistivities. These measurements and their interpretation will be helpful in trying to understand the conditions that exist in the lower crust of this region which must play a role in the ongoing tectonics, and which are presently the subject of a good deal of debate. These measurements should also be able to detect any unusual thermal conditions in the upper mantle which could be related to mantle deformation processes. The ability to determine crustal resistivities from magnetotelluric measurements is due to the fortunate circumstance that the oceanic conductivity-resistivity structure allows the oceanic current system to be brought up onto the California upper crust, and therefore, magnetotelluric measurements can follow the way in which these currents work their way back into the mantle through the lower crust.

这是一个在加利福尼亚州进行大地电磁测量和三维解释的合作项目，重点是确定下地壳和上地幔的电阻率。 这些测量及其解释将有助于试图了解该地区下地壳中存在的条件，这些条件必须在持续的构造运动中发挥作用，并且目前是大量争论的主题。 这些测量还应该能够检测上地幔中任何可能与地幔变形过程有关的异常热条件。 能够通过大地电磁测量确定地壳电阻率是由于幸运的是，海洋电导率-电阻率结构允许洋流系统被带到加利福尼亚上地壳，因此，大地电磁测量可以跟踪这些洋流通过下地壳返回地幔的方式。