二维地电模型多参数反演方法及其在MT测深中的应用

MULTI-PARAMETER INVERSION METHOD OF TWO- DIMENSION GEOELECTRIC MODEL AND IT'S APPLICATION TO MT SOUNDING METHOD

二维地电模型电(电磁)测深法参数化反演,宜采用多参数反演方案.文中导出了多参数反演的基本数学模型,并进行了分解处理,使之变成与剖面上反演点数相等的多个相互独立的小数学模型的组合,用广义逆法逐个求解,即可得一次迭代中整个二维模型参数的修改量.大地电磁测深理论模型和实测数据反演结果表明所提出的二维多参数反演方法可行.它具有稳定的收敛性、较快的收敛速度、能适应较复杂构造的反演和计算量小等特点.

The 2-D parameterization inversion of electric (electromagnetic) sounding data should be solved by using the inversion way of multiparameter. In this paper, we deduced a general mathematical model for the inversion of multi-parameter, which was decomposed into many small independent mathematical models. Their number is equal to that of measuring points. Small mathematical models are solved one by one by generalized inverse matrix method, and the parameter modifier of 2-D geoelectric model is obtained in an iteration. The method have been tested by using MT modeling and field data. The results show that the basic theory of this method is correct. It has some characteristics, such as stable and fast convergence, shorter computation time, detail reconstruction of more complicate geoelectric model etc.