Abstract:Based on the sorting and processing of multi-periods absolute and mobile gravity data of seismic gravity monitoring network, dynamic variation results of the gravity field in different time and spatial domains are calculated for the Jiangsu-Anhui segment of Tan-Lu fault zone. Dynamic variation results of gravity field are decomposed into gravity variation details of different depth levels using the method of wavelet multi-scale decomposition. We discuss the transverse variation of different depth levels and the vertical variation of different time scales combined with regional geological tectonic features. The results indicate that the variation of regional gravity is mainly caused by density change or tectonic activity from the middle and upper crust. The distribution of tectonic activity intensity is not uniform and composed of many sub-sections along the Jiangsu-Anhui segment of Tan-Lu fault zone, influenced by the intersection with the deep fault. The tectonic activities of deep active fault zones have certain control effects on local gravity variations, such as Huaiyin-Xiangshuikou fault and Chuhe fault, because of the obvious gravity gradient zone along the fault zone. In the dynamic variation of wavelet details graph, Tancheng-Sixian section of Tan-Lu fault zone and Huoshan-Lu’an area of Dabieshan orogenic belt, and Liyang-Zhenjiang area of Jiangsu province, have gravity variation zone turns or abnormal areas, but the strength of gradient zone is not high, considering the deep tectonic background of intersection with several deep faults.
LIN Chenghao,LI Zhejun,XU Rugang et al. Wavelet Multi-Scale Decomposition and Tectonic Activity Analysis of the Variation of Gravity Field in Jiangsu-Anhui Segment of Tan-Lu Fault Zone[J]. jgg, 2019, 39(9): 884-889.