A fast estimation method of magnetic-source parameters based on the vertical difference of normalized source strength
HUANG Yuan-Sheng1,2(), WANG Yan-Guo1(), LUO Xiao3
1. School of Geophysics and Measure-control Technology, East China University of Technology, Nanchang 330013, China 2. Hainan Investigation Institute of Hydrogeology and Engineering Geology, Haikou 571100, China 3. No. 230 Research Institute of Nuclear Industry, Changsha 410011, China
Fast automatic inversion is a primary tool for magnetic data interpretation. The normalized source strength (NSS) is one main method for three-dimensional magnetic data interpretation as it is independent of magnetization direction. In this paper, the vertical difference of the normalized source of strength is introduced, and a fast estimation method of magnetic-source parameters based on the vertical difference of normalized source strength is derived in the light of the vertical difference of NSS at different height. In addition, upward continuation of suitable height can be used to improve the stability of the method. Model tests shows that the vertical difference of NSS has higher resolution ability and can recognize the horizontal locations of magnetic sources, and the proposed automatic inversion method can obtain the depths and structural indices of the sources. In this paper, the proposed method is applied to magnetic anomaly of M area over Inner Mongolia, and obtain the horizontal locations, depths and structural indices of magnetic sources. The results could provide useful information for forecasting the distribution of concealed rock mass.
黄远生, 王彦国, 罗潇. 基于归一化磁源强度垂向差分的磁源参数快速估计方法[J]. 物探与化探, 2021, 45(6): 1588-1596.
HUANG Yuan-Sheng, WANG Yan-Guo, LUO Xiao. A fast estimation method of magnetic-source parameters based on the vertical difference of normalized source strength. Geophysical and Geochemical Exploration, 2021, 45(6): 1588-1596.
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