Research on RTP aeromagnetic gradient data and its applicability in different latitudes
Li Lin1, Guo Hua2,3, Wang Ping2,3, and Jia Wei-Jie3
1. College of Geo-exploration Sciences and Technology, ilin University, Chang Chun 130026, China,
2. China University of Geosciences (Beijing), Beijing 100083, China,
3. China Aero Geophysical Survey and Remote Sensing Center, Beijing 100083, China.
Abstract：
Aeromagnetic gradient data needs to be reduced to the pole so that it can be better applied to geological interpretation through theoretical derivation. In this paper, we conduct research on the morphological characteristics of the total and horizontal gradient modules before and after reduction to the pole and design models at different latitudes, with consistent and inconsistent magnetic field direction and geological body magnetization direction. We discuss how to use the total gradient module and horizontal gradient module in geological interpretation. The reduced-to-the-pole (RTP) method is required for the horizontal gradient module method but not for the total gradient module. Finally, the conclusions derived from the theoretical models are verified through analysis of real data. The position determination of a geological body using the total gradient method, gradient data, or total-field data works better without RTP, ensuring data primitive authenticity. However, the horizontal gradient module should be reduced to the pole to determine the boundary of the geological body. Finally, the correction of the designed model is verified by actual data analysis. Both the total and horizontal gradient methods can be applied to geological interpretation.
Li Lin,Guo Hua,Wang Ping et al. Research on RTP aeromagnetic gradient data and its applicability in different latitudes[J]. APPLIED GEOPHYSICS, 2016, 13(1): 48-58.
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2016, Vol. 13 
