Rehydration of the lower crust, fluid sources and geophysical expression

本项目旨在探索一个长期存在的谜团：通过构造稳定地壳的大地电磁成像探测到的深部地壳电导体的起源。这些特征出现在所有时代的克拉通中，通常是横切构造和岩性。本项目旨在探讨这样一种假设，即这些特征是古代深部地壳流体流动的记录，它改变了岩石的电性。利用一个特别暴露的天然实验室，保存无水下地壳的大规模再水化，该项目计划确定流体的来源及其引起的成分变化。然后，它计划通过实验确定流体流动引起的电阻率变化，并利用该数据在地壳尺度上模拟大地电磁响应。

This project aims to explore a long-standing mystery: the origin of deep crustal electrical conductors detected by magnetotelluric imaging of tectonically stable crust. These features occur in cratons of all ages, and commonly cross cut structures and lithologies. This project aims to investigate the hypothesis that such features are the record of ancient deep crustal fluid flow, which modified the rock electrical properties. Using an exceptionally exposed natural laboratory preserving large-scale rehydration of anhydrous lower crust, the project plans to determine the source of fluids and the compositional changes they induced. It then plans to experimentally determine changes in resistivity induced by fluid flow and use that data to model the magnetotelluric response at crustal scale.