基于不等式和Gramian约束的MT和重力正则化联合反演

Regularized joint inversion of magnetotelluric and gravity data based on inequality and Gramian constraints

基于Gramian约束的正则化联合反演是目前地球物理联合反演领域的研究热点。鉴于正则化项和约束项权重系数选择的困难性,有必要在正则化联合反演中引入不等式约束。本文以基于Gramian约束的大地电磁测深法(MT)和重力正则化联合反演为例,对比了惩罚函数法和转换函数法在联合反演中的应用效果,并开展了江西相山某测线的实测资料处理。模型试验表明,惩罚函数法和转换函数法可以有效地将物性参数约束在一定范围之内,惩罚函数法具有更高的灵活性但需要人为设置惩罚函数的权重系数。实测数据的处理表明,基于不等式和Gramian约束的联合反演具有较高的实用性,提高了地球物理解释的精度。

Regularized joint inversion based on Gramian constraints is a hot research topic in the field of geophysical joint inversion.Given the difficulty in selecting weighted factors of the regularization and constraint items,it is necessary to introduce inequality constraints into the regularized joint inversion.To investigate the regularized joint inversion of magnetotelluric(MT)and gravity data based on Gramian constraints,this study compared the application effects of the penalty function method and the transform function method in the joint inversion and processed the measured data of a survey line in Xiangshan,Jiangxi Province.According to the results from model experiments,both methods can effectively constrain petrophysical parameters,and the penalty function method has higher flexibility but requires the artificial setting of the weighted factors.Moreover,the processing of the measured data shows that the joint inversion based on inequality and Gramian constraints is highly practical and can improve the precision of geophysical interpretation.