Structure Features of the Jiuzhou Fault in Langgu Depression

Four shallow seismic survey lines were laid to detect old faults. By reprocessing seismic data, a shallow seismic profile with high signal-to-noise ratio and high resolution is obtained. It clearly shows the shallow structural characteristics of the Jiuzhou fault, combined with the oil seismic exploration profile and the deep seismic reflection profile data. The deep and shallow structural characteristics of the Jiuzhou fault were obtained. In the shallow part, the fault was a positive fault with a steep inclination, and the upper break point was buried 130 to 155 m deep. The time of activity since the Quaternary period was the Middle Pleistocene; The Jiuzhou fault and the other six faults are a group, and together with a fault that tends to SE, a fault basin is formed; The fracture is merged at a depth of about 3.5 km to a fault that is inclined westward, and the lower extension ends on the crystalline base.