A new edge detection method based on the analytic signal of tilt angle (ASTA) for magnetic and gravity anomalies

Abstract

In order to obtain maximum information from magnetic and gravity anomaly maps, application of an edgedetection method is necessary. In this regard two commonly used methods are derivative filters and local phase filters. In this paper, a MATLAB code is expanded to combine an analytic signal filter and a tilt angle filter as a new edge detection filter called ASTA filter. This method was demonstrated on synthetic magnetic data from 3 models and also on real magnetic and gravity data from southwest England. Findings show that the boundaries of a causative body are enhanced more accurately using this new filter, compared with other edge detection filters. The source code in MATLAB format is available from the authors on request.