CONVOLUTION FILTERING OF GRAVITY AND MAGNETIC MAPS

Abstract

This note discusses some applications of convolution filter theory to gravity and magnetic maps. Sampling of the field is equivalent to a multiplication, and the corresponding convolution determines the sampling spectrum. If aliasing is acceptably small a specific filtering multiplication in the wavenumber domain corresponds to a convolution of a set of grid coefficients with gridded map values. The application of this theory to single‐ring residuals, certain vertical derivatives, downward continuation, and low‐pass filtering is discussed.