Collaborative Research: A National Instrument Facility for ElectroMagnetic Studies of the Continents (EMSOC)

小行星9616421 该裁决为收购提供了部分支持 华盛顿大学的便携式磁力计和相关的现场设备将成为集中管理的设备库的一部分，并提供给美国研究人员，用于使用大地电磁（MT）技术对地球深部内部结构进行成像的项目的现场部署。华盛顿大学承诺提供购买设备系统所需的剩余资金。 最近，利用大地电磁法对地壳和上地幔进行遥感，在制作具有良好空间分辨率和内容（电导率）与地震图像（地震速度）不同的内部结构图像方面取得了重大进展。大地电磁法是利用地球外部地磁场的变化在地球内部感应出随时间变化的天然电磁场（EM）来进行大地电磁测深的。感应的电流（大地）扩散到地球，并从电阻率结构的不均匀性散射回来。地表水平磁场和电场之间复杂的频率相关关系称为MT阻抗，可以反演以求解内部的电阻率（或电导率）结构。 内部的电导率特性是相当感兴趣的，因为它们强烈地依赖于导电离子流体或熔体的存在，这是很难或不可能用其他遥感技术检测。 ***

9616421 Booker This award provides partial support for the acquisition of portable magnetometers and associated field equipment by the University of Washington that will become part of a centrally managed pool of equipment and made available to US researchers for field deployment in projects using the magnetotelluric (MT) technique to image the Earth's deep interior structure. The University of Washington is committed to providing the remaining funds necessary to acquire the equipment system. Remote sensing of the Earth's crust and upper mantle using MT methods recently has made significant progress in producing images of internal structures with good spatial resolution and with content (electrical conductivity) that is distinct from seismic images (seismic velocities). The MT method makes use of the time-dependent natural electromagnetic fields (EM) induced inside the Earth by the variations of the Earth's external geomagnetic field. The induced electric (telluric) currents diffuse into the Earth and are scattered back from heterogeneities in the electrical resistivity structure. The complex, frequency dependent, relationship between the horizontal magnetic and electric fields at the surface is called the MT impedance and can be inverted to solve for the resistivity (or conductivity) structure of the interior. Conductivity properties of the interior are of considerable interest because they depend strongly on the presence of conducting ionic fluids or melts which are difficult or impossible to detect with other remote sensing techniques. ***