关键词: 断裂活动性, 第四纪, 中强地震, 青岛

Abstract: A series of studies have been carried out to gain an insight into the Quaternary fault activities in Qingdao City and its surrounding area. The spatial distribution, geomorphic features and the features of the structural planes of the faults, as well as the relation between the faults and Quaternary strata have been studied in detail. Moreover, the ages of the relevant fault zone materials and unfaulted overlying Quaternary deposits have been dated by TL and/or ESR methods. This paper summarizes the achievements of these recent studies. It is concluded that the NE trending faults in Qingdao City and its surrounding area share some similarities in their dimension, orientation, age of faulted rocks, mode of motion, and age of the latest faulting. Their latest active period was in the mid late stage of middle Pleistocene. The faults have no longer been active since late Pleistocene. Moreover, in this area no fault of other strikes has been found to be active since late Pleistocene. According to historical earthquakes, the current activity of small earthquakes and Quaternary fault activities in this area, it is suggested that there's no condition for the occurrence of M_S≥6 earthquakes within this area, but it would not be surprising if an M_S≈5 earthquake should occurs in the future.

Key words: Fault activity, Quaternary, Medium earthquake, Qingdao City