Depth Corrected Edge Detection of Magnetic Data

Most existing edge detection algorithms locate source edge through characteristic values, which are from potential derivatives, e.g., the tilt angle and the theta map locate the edge with zero value and the maximum value, respectively. In the present study, we state that the routine edge detections cannot delineate the accurate edge, especially for deep sources. We propose an idea for the edge detection using the depth correction, and suggest the depth corrected edge detection through the enhanced tilt angle to locate the deep source edge. The utility of depth corrected edge detection is demonstrated using a couple of model tests. Compared with existing methods, the depth corrected edge detection produces superior results by locating edges closer to the true edges, resulting in better interpretative images. In the application from a magnetic anomaly associated with a magnetite ore body from Qinghai Province in northwest China, most of the methods delineate the magnetite ore body's area much larger than the actual one, while the proposed depth corrected edge detection delineate the magnetite ore body very close to the drill holes.