Abstract Based on the comprehensive analysis of gravity and petroleum geophysical exploration data, we study the spatial distribution and Quaternary activity of Yancheng-Nanyang’an fault by shallow seismic exploration and drilling. The results show that the Yancheng-Nanyang’an fault is composed of two faults. The tendency of main fault is NNW and the dip is about 65°-80°. The secondary fault is arc-shaped in the north of Xinyang, with a dip of 70°-80°. Both faults are normal, the upper part is steep and the lower part is slow. The shallow seismic exploration identified the exact position of Yancheng-Nanyang’an fault and its secondary fault in the main urban area of Yancheng. The gravity Bouguer anomaly interpretation shows that the main fault extends in a SW direction. The obvious fracture dislocation variation of the main fault of Yancheng-Nanyang’an fault is about 70 m below the surface, and the upper limit stratum controlled by fault is about 55-70 m below the surface. Based on the shallow seismic exploration and borehole data, we compare and analyze the surrounding faults with the same tectonic environment and strike, the Yancheng-Nanyang’an fault is judged to be an early-middle Pleistocene buried fault. The moderate-strong earthquakes data near Yancheng-Nanyang’an fault shows that there have occurred three earthquakes near the fault. There is an obvious correlation between the earthquakes and Yancheng-Nanyang’an fault, and the future potential earthquake risk is worthy of attention.
ZHANG Shuo,ZHANG Ping,GONG Xulong et al. Research on Quaternary Activity of the Yancheng-Nanyang’an Buried Fault in Jiangsu Province[J]. jgg, 2023, 43(7): 722-727.
ZHANG Shuo,ZHANG Ping,GONG Xulong et al. Research on Quaternary Activity of the Yancheng-Nanyang’an Buried Fault in Jiangsu Province[J]. jgg, 2023, 43(7): 722-727.