The Anomaly Feature Extraction of Mobile Gravity in the Sichuan-Yunnan Region Using Wavelet Transform Method
——The Case Study of the Ludian MS6.5 and Jinggu MS6.6 Earthquakes in 2014
Abstract:In this paper, firstly, we introduce the basic principle of the wavelet transform, discuss and analyze the influence factors of the wavelet multi-resolution decomposition and the wavelet multi-scale decomposition method, select the wavelet basic function of coif5, and propose determining the decomposition order by cross examination method. Secondly, we use this method to effectively separate the local and regional anomalies in the model test, and analyze the reconstruction anomalies qualitatively and semi-quantitatively, combining with the radial logarithmic power spectrum method. Lastly, the wavelet transform is applied to deal with the mobile gravity anomalies of differential dynamic variations of the period of 201309-201404 in the Sichuan-Yunnan region, so as to obtain the multi-scale decomposition anomalies. Furthermore, we find obvious gravity anomalies variation characteristics among D4-D6 anomalies by the wavelet transform, the reconstructed local and regional anomalies in the main earthquake location of Ludian MS6.5 and Jinggu MS6.6 earthquakes in 2014. The above anomalies are analyzed and explained in combination with the information of geological structures in this area.
ZHANG Shuangxi,CHEN Zhaohui,WANG Qinghua et al. The Anomaly Feature Extraction of Mobile Gravity in the Sichuan-Yunnan Region Using Wavelet Transform Method
——The Case Study of the Ludian MS6.5 and Jinggu MS6.6 Earthquakes in 2014[J]. jgg, 2020, 40(1): 87-93.