Abstract:We use wavelet multi-scale analysis method to separate the gravity field in Jiangsu coastal area, and obtain the details of multi-order gravity wavelet. We obtain the spatial distribution of depressions and uplifts in different depths by analyzing the details of different order wavelets, and then provide constraints on the orientation and tendency of seven deep faults in the study area. We find that the orientation and tendency of most of the faults in the north of Xinghua-Dafeng line tend to be NNE and NW, respectively, with steep slopes; while in the south of the Xinghua-Dafeng line, the orientation and tendency of most of the faults are NEE and SE, respectively, and with relatively small slopes. We suggest that the difference patterns between these faults may be a reflection of the ramp structure of the lower Yangtze. After a combination with seismic observations, we find that the distribution of earthquakes is closely related with faults with NE-NEE, NW and nearly EW orientations. Therefore, the faults in the northwest of Donghai-Ganyu and Dafeng harbor exhibit strong activities and unstable stress field, and we speculate there is a higher risk of earthquakes in this area.
ZHANG Dalian,ZHANG Ping,LI Xiangqian et al. Characteristics of Wavelet Multi-Scale Gravity Field and Analysis of Tectonic Activity in Jiangsu Coastal Area[J]. jgg, 2021, 41(2): 186-191.