各向异性海底地层海洋可控源电磁响应三维积分方程法数值模拟

采用积分方程法对各向异性海底地层海洋可控源电磁（MCSEM）响应进行三维数值模拟.首先利用算子理论给出各向异性海底地层中的压缩积分方程，由于满足压缩映射条件，该积分方程在任意参数下总是迭代收敛的.然后为了提高计算效率，引入分区域多重网格准线性近似技术.通过具体算例验证了所述算法在计算精度与效率方面的有效性.最后利用该算法考察并分析了海底地层的各向异性对MCSEM三维响应特征的影响. 关键词： 海洋可控源电磁法 各向异性 三维模拟 积分方程法

Three-dimensional numerical modeling of marine controlled-source electromagnetic responses in a layered anisotropic seabed using integral equation method

We perform a numerical simulation of marine controlled-source electromagnetic （MCSEM） responses in a layered anisotropic seabed using integral equation method. Firstly, we use the operator theory to deduce the contraction integral equation, which is always convergent regardless of any parameters, for it satisfies the contraction mapping condition. Then we introduce the subdomain multigrid and quasi-linear approximation to improve the computation efficiency. We also validate the accuracy and efficiency of the algorithm by synthetic numerical modelings. Finally, we simulate the three-dimensional MCSEM responses in the layered anisotropic seabed, and investigate the effects of anisotropy.