Wavenumber domain generalized inverse algorithm for potential field downward continuation
位场向下延拓的波数域广义逆算法

Downward continuation is an important operation in potential field data processing and inversion,but its instability problem influences its application in many processing and inversion techniques.In this paper,taking 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 3-D theoretical model data and real magnetic field data give ideal results.