The North China Plain (NCP) is one of the most populated and economically developed areas in China, and is a region with high level of seismic hazards. Study on the Quaternary activity of the faults and the seismogenic mechanism of the large earthquakes in NCP is conducive to exploring the seismogenic pattern of intraplate earthquakes and reducing the damage caused by seismic hazards.The Liaocheng-Lancao fault is an important buried deep major fault in the south-central part of the NCP. In this study, the activity of the Liaocheng-Liaocao fault is finely studied by combining shallow seismic exploration, drilling and Quaternary dating methods.The Bachengsi drilling reveals that the southern segment of the Liaocheng-Lancao fault displaces the bottom boundary of the Holocene and is an early Holocene active fault. It also reveals four paleoseismic events since the Late Pleistocene, with vertical displacement of 1.2±0.2-3.7±0.2 m for a single event. Based on the stratigraphic offsets in the boreholes, the average vertical slip rate of this fault is calculated to be about (0.1±0.05) mm/a for the early Late Pleistocene and (0.35±0.04) mm/a for the late Late Pleistocene-middle Holocene. Based on the distribution of isoseismic lines and surface ruptures of the 1937 Heze M 7.0 and M 6 earthquakes, the Xiaoliu-Xieyuanji fault and the Dongming-Chengwu fault are considered to be the seismogenic faults. The Liaocheng-Lancao fault has a good controlling and restraining effect on the accumulation of stress and the occurrence of earthquakes in the area, and is the seismic controlling fault of this earthquake.
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