基于阻尼型高斯牛顿法的三维直流电阻率反演

直流电阻率法是浅层水文、工程、环境、考古等与人类社会生活密切相关探测领域的重要手段。地下目标体多表现为三维电性结构,因此,需要对直流电阻率法的三维正反演进行研究和探索。本文利用阻尼型高斯牛顿法的三维直流电阻率反演方法,在迭代的过程中,避免了直接计算偏导数矩阵,而只需计算偏导数矩阵及其转置与任一向量的乘积,同时结合预处理的共轭梯度法求解模型修正量,节省了内存存储量,加快了反演速度。通过对不同模型进行模拟计算,反演结果与实际模型吻合的很好。

3D DC Resistivity Inversion Based on Damped Gaussm Newton Method

3--D DC resistivity method has been used in the detecting fields of shallow hy- drology, engineering, environment, archaeology and those that are closely related to hu- man social life. The underground torgets are presented as three--dimensional electrical structure. Therefoi＇e, it is necessary to study and explore 3--D forward and inversion tech- nology of DC resistivity methods. In this paper, we use the damped Gauss--Newton meth- ods of 3--D DC resistivity inversion. In the Gauss--Newton iteration, we avoid direct and complicated computations of the derivative matrix, and combine preconditioned conjugate gradient method to get the model update. This method can decrease the memory storage ca- pacity and speeds up the inversion calculation. Different models have been computed, and the inversion results matches the actual models very well.