Magnetic interpretation using the 3-D analytic signal

Abstract

A new method for magnetic interpretation has been developed based on the generalization of the analytic signal concept to three dimensions. The absolute value of the analytic signal is defined as the square root of the squared sum of the vertical and the two horizontal derivates of the magnetic field. This signal exhibits maxima over magnetization contrast, independent of the ambient magnetic field and source magnetization directions. Locations of these maxima thus determine the outlines of magnetic sources. Two examples are shown of the application of the method: 1) the analytic signal highlights a circular feature beneath Lake Huron that has been identified as a possible impact crater, and 2) illustrates the continuation of terranes across the Cabot Strait between Cape Breton and Newfoundland. -from Authors