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针对江汉盆地海相地层的地电结构特点，对区内5口探井的物性数据作了统计，给出了一维层状介质模型。大地电磁数据是采用一维层状介质递推关系式模拟，差商法求其偏导数；地震数据是以水平界面为基础进行快速射线追踪正演，运用解析法求偏导数。理论数据采用典型HAK型曲线5层地球物理模型试算。在上述基础上，本文着重阐述了大地电磁和地震联合反演方法，首先引入模型空间向量，其参数由各层的速度、电阻率和厚度构成，并给出此模型的响应函数，然后将响应函数和数据向量建立统一的映射关系。由于不同的数据集具有不同的物理空间和数量级，必须作归一化处理，引入相对预测误差向量，为此，文中给出一种求解不适定问题的方法。理论模型和实际数据联合反演结果表明，它优于任何一种单一的地球物理反演方法。
According to the characteristics of geoelectric structure of marine strata in Jianghan Basin, the physical property data of five exploration wells in the area are calculated, and the one-dimensional layered media model is given. The magnetotelluric data of the earth are modeled by the one-dimensional layered media recursion relation and the difference quotient method is used to derive the partial derivative. The seismic data is a fast ray tracing forward based on the horizontal interface, and the analytical derivative method is used to find the partial derivative. The theoretical data is based on a 5-layer geophysical model of a typical HAK curve. Based on the above, this paper focuses on the joint inversion method of geomagnetic and seismic. Firstly, the model space vector is introduced. The parameters are composed of velocity, resistivity and thickness of each layer. The response function of this model is given, and then the response Function and data vector to establish a unified mapping. Because different datasets have different physical spaces and orders of magnitude, they must be normalized and introduced into relative prediction error vectors. Therefore, a method for solving ill-posed problems is given in this paper. The combined inversion of the theoretical model and the actual data shows that it is superior to any single geophysical inversion method.