A simple derivation of Cordell’s stripping filter

Abstract

The presence of a strong regional (deep source) anomaly often makes the identification of local (shallow source) anomalies difficult. It may become necessary to either separate the regional and the residual, or carry out an operation on the observed map that enhances the local anomalies at the expense of the regional background. The problem of separation of deep and shallow‐source potential field anomalies is one of the oldest problems in geophysics. Various authors (Griffin, 1949; Nettleton, 1954; Abdelrahman et. al., 1985, for example) have presented details and schemes for separating residual and background anomalies. More recently, Cordell (1985) through Green’s equivalent stratum theorem obtained a filter in the frequency domain that may be used for separating shallow and deep‐source potential field anomalies.