该文以Matlab为程序编译工具,采用双二次插值的有限单元法,推导出频率域可控源电磁法二维正演的计算公式。为了模拟无穷远边界及满足计算机的内存需求,在保证计算精度的情况下设计了非均匀网格剖分。在程序编制中,只存储有限元系数矩阵的非零元素,大大减少了正演计算的时间。通过对均匀半空间和二维模型电磁响应的计算,获得了相应的视电阻率和阻抗相位曲线,验证了算法的正确性。 In this paper, the finite element method of bi-quadratic interpolation is used to compile the program by Matlab, and the formula of two-dimensional forward modeling of the controlled-source electromagnetic method in frequency domain is deduced. In order to simulate the infinity boundary and meet the memory requirements of the computer, non-uniform mesh subdivision was designed while guaranteeing the accuracy of calculation. In programming, only the non-zero element of the finite element coefficient matrix is ​​stored, which greatly reduces the time for forward calculation. The corresponding apparent resistivity and impedance phase curves were obtained through the calculation of the electromagnetic response of the uniform half-space and two-dimensional model, which verified the correctness of the algorithm.