Edge detection based on curvature of gravity gradient tensors

Recently, the curvature of gravity gradient tensors is widely used in processing and interpretation of gravity data. In order to extend the application of this parameter, the local reference system based on the related theory of local rotation is discussed for the correct calculation of curvature using gravity vectors and gradient tensors. And a single sphere and prism as an example is taken to illustrate the correctness of this theory. Then, the correctly calculated curvature of gravity gradient tensors is applied to the edge detection of gravity data. Finally, using the synthetic models and real data, the application effect of various curvatures in edge detection was analyzed and discussed. The results show that the local rotation coordinate system based on the equipotential surface is a prerequisite for correct calculation of various curvatures, which corrects the misunderstanding in the calculation of the curvature. In the edge detection, the Gauss curvature calculated in the local coordinate system can better delineate the edge of the underground geological body.