The Enhancement of Magnetotelluric Surveying via Natural Wave Field Predictions and Artificial Wave Injection Experiments

利用超低频电磁波揭示地下地质结构的大地电磁(MT)技术正在成为地质勘探的越来越重要的工具，特别是在标准地震方法实施成本高昂或产生模糊结果的情况下。目前的大地电磁方法的一个主要缺点是依赖于零星出现的这种海浪的自然震源或高度局部化的受控震源，其形式是由远洋勘测船拖着的小型发射机。在过去的三十年里，已经开发了一些技术，通过使用地面发射器发出的调制高功率高频无线电波照射地球上层大气，人为地激发出超低频电磁波。该方案将探索利用这种实验和预报自然产生的海浪，以提高目前大地电磁测量技术的效率和成本效益。

Magnetotelluric (MT) techniques, which employ ultra low frequency electromagnetic waves in order to reveal subsurface geological structures are becoming increasingly important tools for geological exploration, particularly under conditions where standard seismic methods are expensive to implement or produce ambiguous results. A major drawback of present MT methods is a reliance on sporadically occurring natural sources of such waves or highly localised controlled sources in the form of a small transmitter towed along by an ocean going survey vessel. Over the past three decades techniques have been developed which allow ultra low frequency electromagnetic waves to be artificially excited in the Earth's upper atmosphere by irradiating it with modulated high power, high frequency radio waves from ground-based transmitters. This programme will explore the use of such experiments, and the forecasting of naturally-occurring waves, in order to improve the efficiency and cost-effectiveness of current MT survey techniques.