基于解析雅克比矩阵的E-E_x广域电磁法一维并行约束反演

对于野外实测数据的反演解释,一维反演仍然占据着重要地位。提出一种使用探测深度和等对数域剖分的方式来剖分层厚、只进行电阻率单参数反演的方案。反演时,先使用MT反演来建立初始模型,之后采用MATLAB自带的parfor循环和最优化工具箱来进行最优化计算,使用解析法来计算雅克比矩阵,从而大大提高了计算速度。对于实际地电模型,充分考虑到已有的先验信息,通过使用井震约束反演有效降低了反演多解性,使反演结果更加接近真实的地层情况。

One-dimension parallel constrained inversion of E-Ex wide field electromagnetic method based on analytical Jacobian matrix

For the interpretation of measured data,1D inversion still occupies an important position.In this paper,we propose a scheme which segments the layers using probing depth and equally in logarithmic domain,and only carries out single parameter inversion of resistivity.First,the MT inversion is used to establish the initial model.Then,parfor loop and optimization toolbox coming with MATLAB is used to optimize the calculation.In this process,analytic method is used to calculate the Jacobian matrix and greatly improves the speed of calculation.In addition,for the actual geoelectric model,we use the constraint inversion which can take the existing prior information into account and reduce the inversion multi-solution effectively,to make the inversion result closer to the real ground situation.