Magnetotelluric data inversion with seismic data constraint

Abstract

In the paper we present a new method to invert the interior structure in the basement or ancient hidden hill by using magnetotelluric (MT) data with seismic data constraint. We first obtain the thickness and resistivity of each layer above the basement or buried hill by the inversion of seismic and log data and create a geoelectrical model for the layers above the basement or hidden hill. Then with the reference to the inversion of 1D MT data, a geoelectrical model for the layers below the basement or hidden hill is created. On the basis of the above initial model, we present an effective and practical forward method, i.e., a model-matched approach to conduct forward inversion arithmetic. Finally, by the method of conjugate gradient iteration, a forward and backward iterative calculation is made. Taking No. 618 profile of Shengli Oil Field as an example, we have found out that the tectonic information that is unreflective in the seismic data below the basement is better reflected in the inversion result.