SEGMENTATION CHARACTERISTICS AND ACTIVITY OF CIXIAN-DAMING FAULT

Based on analysis of the latest data obtained from the project of active fault surveying in Handan city, combined with field investigation and the explanation of seismic profile from oilfield, the segmentation of Cixian-Daming fault is studied.According to analysis of digging trench and testing sample's age, we discuss the activity of Cixian-Daming fault.It is shown that Cixian-Daming fault is divided into 3 segments, which are Daming-Linzhang segment, Cixian-Fengfeng segment and Nanshancun-Chakou segment.It can be deduced that the activity of middle segment of Cixian-Daming fault is steady since late Pleistocene based on the result of sample's ages, while the activity of west segment is active based on topography investigation and the latest study, which was surface fracture belt formed by the earthquake occurred in 1830.According to geological data of oilfield, the depth of Daming-Linzhang segment is buried deeply to 1200m.Even so, its activity should be studied because of a few earthquakes occurred along the fault.Surface fracture belt cannot be found along Cixian-Fengfeng segment for thick upper sediment.The depth of each upper breakpoint gradually turns shallow because of the thickness of the upper sediment turning thin.Therefore surface fracture belt can be easily found along Nanshancun-Chakou segment.