印模法在AMT数据处理中的改进与应用

The improvement and applications of the impression method in AMT data processing

在AMT数据处理中,反演模型的构建决定了最终的反演结果,不合理的反演模型直接导致反演结果的偏差。利用前人提出的印模法思想,对该方法进行了一些改进:以一维TM模式平均电阻率为均匀半空间模型电阻率进行二维反演,并以此反演结果作为元模型,全区一维平均电阻率为辅模型,理论探测深度为印模深度,构建新的反演模型。通过实例对比,认为采用该方法建立的模型能够较好地反映相应的地电结构,达到全区的平衡和统一,具有较好的应用效果。

In AMT data processing,inversion model construction determines the final inversion,whereas the inversion model of unreasonable deviation leads to erroneous inversion result. Based on thought of previously proposed impression method,the authors made some improvements in this paper： 2D inversion is conducted by using the average resistivity of one-dimensional TM model as uniform half space model resistivity and then,with the inversion result as the element model,the average resistivity as the auxiliary model,and the theoretical probing depth as theimpression depth,a new inversion model is constructed. Comparative studies of examples show that the methods used in this model can better reflect the corresponding geoelectric structure and achieve the balance and unity in the region,thus exhibiting good application effect.