The polar regions are host to fundamental unresolved challenges in Earth studies. The nature of these regions necessitates the use of geophysics to address these issues, with electromagnetic and, in particular, magnetotelluric studies finding favour and being applied over a number of different scales. The unique geography and climatic conditions of the polar regions means collecting magnetotelluric data at high latitudes, which presents challenges not typically encountered and may result in significant measurement errors. (1) The very high contact resistance between electrodes and the surficial snow and ice cover (commonly MΩ) can interfere with the electric field measurement. This is overcome by using custom-designed amplifiers placed at the active electrodes to buffer their high impedance contacts. (2) The proximity to the geomagnetic poles requires verification of the fundamental assumption in magnetotellurics that the magnetic source field is a vertically propagating, horizontally polarised plane wave. Behaviour of the polar electro-jet must be assessed to identify increased activity (high energy periods) that create strong current systems and may generate non-planar contributions. (3) The generation of ‘blizstatic’, localised random electric fields caused by the spin drift of moving charged snow and ice particles that produce significant noise in the electric fields during periods of strong winds. At wind speeds above ~ 10 m s −1 , the effect of the distortion created by the moving snow is broad-band. Station occupation times need to be of sufficient length to ensure data are collected when wind speed is low. (4) Working on glaciated terrain introduces additional safety challenges, e.g., weather, crevasse hazards, etc. Inclusion of a mountaineer in the team, both during the site location planning and onsite operations, allows these hazards to be properly managed. Examples spanning studies covering development and application of novel electromagnetic approaches for the polar regions as well as results from studies addressing a variety of differing geologic questions are presented. Electromagnetic studies focusing on near-surface hydrologic systems, glacial and ice sheet dynamics, as well as large-scale volcanic and tectonic problems are discussed providing an overview of the use of electromagnetic methods to investigate fundamental questions in solid earth studies that have both been completed and are currently ongoing in polar regions.

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电磁学在极地地球成像中的应用

极地地区面临着地球研究中尚未解决的根本挑战。这些区域的性质需要使用地球物理学来解决这些问题，电磁研究，特别是大地电磁研究受到青睐并被应用于许多不同的尺度。极地地区独特的地理和气候条件意味着在高纬度收集大地电磁数据，这带来了通常不会遇到的挑战，并可能导致重大的测量误差。(1) 电极与地表冰雪覆盖层之间非常高的接触电阻（通常为 MΩ）会干扰电场测量。这可以通过使用放置在有源电极处的定制设计放大器来缓冲其高阻抗触点来克服。(2) 靠近地磁极需要验证大地电磁学中的基本假设，即磁场是垂直传播的、水平极化的平面波。必须评估极地电射流的行为，以确定增加的活动（高能量时期），这些活动会产生强电流系统并可能产生非平面贡献。(3) 由移动带电雪和冰粒子的自旋漂移引起的“blizstatic”局部随机电场的产生，在强风期间在电场中产生显着噪声。在风速高于 ~ 10 m s -1 时，移动的雪造成的失真效果是宽带的。站点占用时间需要足够长，以确保在风速较低时收集数据。(4) 在冰川地形上工作会带来额外的安全挑战，例如天气、裂缝危险等。在现场位置规划和现场操作期间将登山者纳入团队，可以正确管理这些危险。介绍了涵盖极地地区新型电磁方法的开发和应用的研究示例，以及针对各种不同地质问题的研究结果。讨论了侧重于近地表水文系统、冰川和冰盖动力学以及大规模火山和构造问题的电磁研究，概述了使用电磁方法调查已完成的固体地球研究中的基本问题目前正在极地地区进行。