金沙江乌东德水电站区热水塘断层活动性研究

乌东德水电站预可行性研究阶段,陆车林、尖山包、河门口、白滩、三台子、乌东德六个比选坝址中,热水塘断层穿过其中河门口和白滩两个坝址。为了查明该断层规模、性状、活动性,作者在航片解译的基础上,经过野外验证和地质追踪调查,分析了沿断层带的地形地貌、地层岩性、岩溶发育特征,确定了该断层的性质。通过取岩样测年及显微构造等多种方法对断层的活动性进行了深入研究,认为该断层在中更新世前有一定的活动性,但后期活动性明显减弱,晚更新世后没有活动。综合地震资料分析,该断层不是工程活动断层,为坝址比选提供了重要依据。

ACTIVITIES OF THE RESHUITANG FAULT AT THE DAMSITE REGION OF THE WUDONGDE HYDROPOWER STATION ON THE JINSHAJIAN RIVER

In the pre-feasibility study for the Wudongde Hydropower station,six alternative dam sites,i.e.,Luchelin,Jinshangbao,Hemengkou,Baitan,Santaizi and Wudongde were evaluated.The Reshuitang Fault traverses both the Hemengkou and Baitan dam sites,therefore,it is very important to understand activities of the fault.In order to identify the scale,property and activities of the fault,the authors made a detail analysis of the geomorphologic,lithologic and karstic features along the fault based on interpretation of the aerial photos and field investigation.With geodating and microscopic structural analysis,the authors concluded that the fault was active before middle Pleistocene Epoch,but became less active afterwards and completely ceased after late Pleistocene Epoch.Additional seismic analysis confirmed that Reshsuitang Fault is no longer active.