辽宁瓦房店温坨子原核电站场址东岗断裂的活动性

ACTIVITY OF THE DONGGANG FAULT NEAR THE ONCE CHOSEN SITE OF NUCLEAR POWER STATION AT WAFANGDIAN, LIAONING PROVINCE

位于辽宁瓦房店温坨子的东岗断裂是一条隐伏断层 ,靠近该地区原曾选定的核电站场址。通过详细的野外地质工作 ,查明了该断裂的地理位置、几何形态 ,发现断裂带东延至尉屯就转向北去 ,并确定它没有与金州断裂相接。经系列探槽的开挖 ,断层构造岩及有关地层样品作绝对年龄测定 ,证明东岗断层错断了中更新世地层 ;但约 5万年以来断层的上覆地层没有被错断 ,因此认为东岗断层不是能动断层。

The Donggang fault, located at Wentuozi town, Wafangdian city, Liaoning Province, is a hidden fault which is not far from the once chosen site of a nuclear power station. Through detailed field investigation, we have determined the location and geometry of the fault. It is found that the fault turns toward north when it extends eastward to Weitun. It does not link with the Jinzhou fault zone. By trench observations and dating of fault rocks and stratum samples, it is proved that the fault has dislocated the stratum of middle Pleistocene. However, the overlying stratum of the fault is not offset since about 50 000 years. It is concluded that the Donggang fault is not a capable fault.