Wavenumber Domain Generalized Inverse Algorithm for Potential Field Downward Continuation

Abstract

AbstractDownward continuation is an important operation to potential field data processing and inversion, but its instability problem influences its application in many processing and inversion techniques. In this paper, through viewing the downward continuation of potential field as an inverse problem of upward continuation, we obtain a convolution type linear integral equation for downward continuation. Making use of the orthogonal symmetry characteristic of Fourier transform matrix, and combining the principles of singular value decomposition of matrix and generalized inverse, we proposed a stable generalized inverse method for downward continuation of potential field, called wavenumber domain generalized inverse algorithm, which doesn't need the computation for inverse matrix. It resolves the instability of potential field downward continuation of large depth. The applications of the method to the downward continuation of 3D theoretical model data and real magnetic field data give ideal results.