Linear feature analysis for aeromagnetic data

Abstract

This paper presents a new approach to detecting and two approaches to displaying lineaments associated with high-angle magnetic contacts, based on analysis of the curvature of the total horizontal gradient of the total magnetic field reduced to the pole. The first display is a contour or color plot of minus the principal curvature of largest absolute value. The second is a point plot of the local maxima of minus the largest principal curvature in regions where this curvature is negative. The paper also develops a depth-estimation technique for magnetic contacts based on the ratio of the curvature of the total gradient to the total gradient itself. Tests on synthetic data yield excellent results in detecting and delineating magnetic contact edges, and reasonable performance in producing depth estimates for the magnetic contacts. Results obtained using aeromagnetic data from the Finger Lakes region of New York State show good correlation with known structural features.