Edge enhancement of potential field data using an enhanced tilt angle

Abstract

AbstractWe present an edge-detection technique for the enhancement of potential field data, which is based on the tilt angle of the first order vertical derivative of the total horizontal gradient. The technique can be performed using three steps, as follows: first, we calculate the total horizontal gradient of the potential fields, which is stable and effective in determining the horizontal locations; second, we calculate the first order vertical derivative of the total horizontal gradient to increase the vertical-resolution on the basis of the determined the horizontal locations; finally, we display the tilt angle of the first order vertical derivative of the total horizontal gradient tending to balance the amplitude responses from both shallow and deep sources. This technique is designed to reflect the complex distributions of multiple sources with different depths and extents. The effectiveness of our method is demonstrated by synthetic data. The results indicate that the new filter generates more subtle detail for superimposed sources, compared with other edge detection filters. The method is also applied to field surveyed data from the Saskatoon area of Canada, and the results are helpful for qualitative interpretation.An edge-detection technique for the enhancement of potential field data, which is based on the tilt angle of the first order vertical derivative of the total horizontal gradient, is presented. The new filter clearly enhances the edges of superimposed sources sharply and generates more subtle detail. Key words:: edge enhancementpotential fieldssuperimposed sourcestilt angle AcknowledgementsThe authors acknowledge the support of the National Science and Technology Specific Project (2011ZX05005–005–009HZ, 2011ZX05023–003–003), and Specialised Research Fund for the Doctoral Program of Higher Education (20110072110017). They also thank the Geological Survey of Canada (GSC) for permission to use the gravity and magnetic data in Figures 5a and 6a, and the anonymous reviewers for their constructive comments on the manuscript.