TAILIEUCHUNG - Application of directional derivative method to determine boundary of magnetic sources by total magnetic anomalies

This paper presents the Directional Derivative method to determine location and boundaries of the magnetic directional structure sources through a new function DG (Directional Gradient - DG). Algorithm and computer program are made a code by Matlab language to attempt to calculate on 3D models in the compare with Horizontal derivative method (HG). | Vietnam Journal of Earth Sciences, 39(4), 360-375, DOI: Vietnam Academy of Science and Technology (VAST) Vietnam Journal of Earth Sciences Application of directional derivative method to determine boundary of magnetic sources by total magnetic anomalies Nguyen Thi Thu Hang1, Do Duc Thanh*1, Le Huy Minh2 1 Hanoi University of Science (VNU) 2 Institute of Geophysics (VAST) Received 27 May 2017. Accepted 01 September 2017 ABSTRACT This paper presents the Directional Derivative method to determine location and boundaries of the magnetic directional structure sources through a new function DG (Directional Gradient - DG). Algorithm and computer program are made a code by Matlab language to attempt to calculate on 3D models in the compare with Horizontal derivative method (HG). A new function DG also applied to determine the boundary of magnetic sources by the total magnetic anomalies of Tuan Giao region. The result shows that with the application of new function DG, the boundaries of magnetic sources are exactly defined although they have a directional structure and small horizontal size. Moreover, because it does not depend on directions of magnetization, so in the computation, the transformation of the magnetic field to the pole can ignore, thus, reduce transient error. Alternatively, with the application of new function DG, the interferences in case the sources distributed close together are overcome. This usefulness affirms the possibility of application of the this method in the analysis and interpretation of magnetic data in Vietnam. Keywords: Magnetic anomaly; Magnetized prism; Horizontal Gradient; Directional Gradient; Tuan Giao. ©2017 Vietnam Academy of Science and Technology 1. Introduction* In magnetic exploration, the quantitative interpretation or the solution of the inverse problem to determine the location, shape, depth, magnetization of geological objects causing observed anomalies .

• Địa Lý
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