电阻率层析成像非线性反演

Nonlinear inversion for electrical resistivity tomography

本文通过概率成像法、α中心法、遗传算法的有机结合,实现了2-D 电阻率层析成像非线性反演.首先,根据概率成像结果指示出的2-D 地质异常体的相对电性和大致分布范围,合理地确定出α中心的位置与强度系数的变化范围.其次,以α中心法作为2-D地电结构的正演手段,采用遗传算法反演出各α中心的强度系数.在此基础上,应用α中心法重新构建出地下介质电阻率的分布.通过对均匀半空间中赋存2-D 地质异常体模型的反演试验,获得了令人满意的结果.

The paper develops a 2-D tomography survey by using probability distribution scopes of anomalous bodies nonlinear inversion approach for electrical resistivity tomography, α centers, and genetic algorithm. First, the and the positions as well as coefficient ranges of αcenters are determined based on the results of multiple superimposed probability tomography. Secondly, we use α centers method to numerical simulation of 2 D electrical structures and the intensity coefficients of α centers are obtained by the genetic inversion algorithm. Last, the resistivity distribution is reconstructed by using a center method. To test the effectiveness of the approach, several models of 2-D anomalous bodies imbedded in half homogeneous space are used to implement inversion and the results are satisfactory.