Abstract The current local wavenumber methods for the interpretation of magnetic anomalies compute the locations of geological bodies by solving complex matrices. Presently, such methods require to know the structural index, which is a parameter that represents the source type. The structural index is hard to know in real data; consequently, the precision of current methods is low. We present the fast local wavenumber (FLW) method, and define the squared sum of the horizontal and vertical local wavenumbers as the cumulative local wavenumber. The FLW method is the linear combination of the umulative local wavenumberand other wavenumbers, and is used to compute the locations and structural index of the source without a priori information and matrix solution. We apply the FLW method to synthetic magnetic anomalies, and the results suggest that the FLW method is insensitive to background and oblique magnetization. Next, we apply the FLW method to real magnetic data to obtain the location and structural index of the source.
This work was supported by the National Key Research and Development Program of China (Nos. 2017YFC0601305, 2017YFC0602203, and 2017YFC0601606), National Science and Technology Major Project task (No. 2016ZX05027-002-03), National Natural Science Foundation of China (No. 41604098), and State Key Program of National Natural Science of China (No. 41430322).
Cite this article:
. Fast local wavenumber (FLW) method for the inversion of magnetic source parameters[J]. APPLIED GEOPHYSICS, 2018, 15(2): 353-360.
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