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

这是一个在加利福尼亚进行大地电磁测量和三维解释的合作项目，将集中于确定下地壳和上地幔的电阻率。这些测量结果及其解释将有助于了解该地区下地壳中存在的条件，这些条件必须在正在进行的构造运动中发挥作用，并且目前是许多争论的主题。这些测量还应该能够探测到上地幔中可能与地幔变形过程有关的任何不寻常的热状况。从大地电磁测量中确定地壳电阻率的能力是由于一个幸运的情况，即海洋电导率-电阻率结构允许洋流系统被带到加利福尼亚的上地壳，因此，大地电磁测量可以跟踪这些电流通过下地壳返回地幔的方式。

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.