二维层状介质大地电磁视电阻率相位联合快速反演

建立了二维层状介质模型,反演参数为每层的电阻率及各层的底界深度,利用视电阻率和相位进行二维联合反演.利用RRI法（快速松弛反演）通过有限单元法正演快速计算一维偏导数,引入一组修正系数把用RRI法计算的一维偏导数转化为二维偏导数,并且在二维偏导数矩阵中只保留对本测点下的模型参数的偏导数,而忽略掉对其他测点下的参数的偏导数,形成一个近似的雅可比矩阵.通过一个二维三层模型试算,验证视电阻率和相位联合反演能稳定收敛并在一定程度上减小多解性.

Fast Magnetotelluric Joint Inversion of Apparent Resistivity and Phase for Two Dimensional Layered Structure

A two-dimensional layered structure model is constructed. The inversion parameter is the resistivity and bottom depth of each layer. A fast magnetotelluric joint inversion of apparent resistivity and phase for two dimensional layered structure is proposed. The one-dimensional Jacobian matrix is calculated by the RRI （rapid relax inversion） method. The two-dimensional Jacobian matrix is calculated from one-dimensional Jaeobian ma- trix by a set of correction coefficients. In the two-dimensional Jacobian matrix, only the parameters under the site have partial derivatives, others are all zero. A two-dimensional synthetic model of three layers is used to prove the joint inversion of apparent resistivity and phase can converge stably and reduce the non-uniqueness of inversion in a certain extent.