The Approach to Parametric Multidimensional Inversion of Marine Electrical Prospecting Data Considering Bathymetry

Abstract

SUMMARYThis paper proposes the approach to multidimensional inversion of the marine electrical prospecting data in the time-domain, which are obtained using the Differential Normalized Method of Electrical Investigation (DNME). This approach is based on the parametric (model-based) nonlinear multidimensional inversion with the simultaneous recovery of the borders coordinates of the 3D inhomogeneities and their electrophysical properties (electrical conductivity and polarizability). The solution of forward problems and calculation of the field of the impact of geoelectrical model parameters are performed with the use of the finite element method. The inversion is carried out in two stages including the division of measured signals into the electrodynamic component and signals of the induced polarization field. The subhorizontal borders of structural parts of the geoelectrical model can be either fixed (for example, according to the sea depth variations or borders, obtained by seismic methods) or recovered. The possibilities of the proposed approach are shown with the use of synthetic data for the generalized geoelectrical model which was constructed on the basis of the results of the DNME data interpretation obtained in several sea areas.