Source parameters estimation by the normalized downward continuation of gravity gradient data

Abstract

Normalized downward continuation (NDC) method calculates the normalization on the analytical signal modulus of the downward continued field or the downward continuation of the potential field itself, which is used to obtain the edges position and buried depth information. In this study, we applied the NDC method to the edge detector defined as the combination of the directional total horizontal derivatives (DTHD) to improve the lateral resolution. The iterative downward continuation is introduced in the computation process which has a large downward continuation distance. The synthetic gravity data with and without noise are used to test the effectiveness of the new presented approach. The results show that NDC applied to the edge detector based on DTHD has a better resolution than the previous method based on the directional analytic signals, and the source edges and depth information can be obtained simultaneously. Finally, we apply the method to the gravity data acquired over the Humble Salt Dome in USA. The results show a good correspondence to the previous work results.