大地电磁测深多尺度解释策略研究

如何提高大地电磁法对不同深度、不同规模异常体的分辨率/识别能力是其面临的主要问题之一.针对此问题,文章从大地电磁测深最优化反演的概念出发,提出大地电磁多尺度解释策略的概念,通过建立典型地电模型,对比分析了全频数据、高频数据以及不同剖面长度的大地电磁正演模拟和反演计算结果,论证了多尺度解释策略既能有效识别深部总体构造轮廓,也能有效识别浅部不均匀异常体的空间分布特征.从理论上为提高大地电磁法在实际工作中的解释分辨率及解释精度提供了较好的技术参考.

One of the main problems of magnetotelluric method is how to improve the resolution/recognition ability for different depths and different scale anomalies. For this issue, based on the concept of optimal inversion of magnetotelluric sounding, this paper proposes the concept of multi-scale interpretation strategy of magnetotelluric sounding. By establishing a typical geoelectric model, the results of magnetotelluric forward modeling and inversion of full frequency data, high frequency data and different section lengths are compared and analyzed, and it is proved that the multi-scale interpretation strategy can effectively identify the overall deep structural outline and can also effectively identify the spatial distribution characteristics of shallow non-uniform abnormal bodies. Theoretically, it provides a good technical reference for improving the interpretation resolution and accuracy of magnetotelluric method in practical work.