中波水电站水库诱发地震预测研究  

Research on forecast of earthquake induced by reservoir of Zhongbo Hydropower Station

作　　者：贺为民[1] 杨杰[1] 

机构地区：[1]中国地震局地球物理勘探中心,河南郑州450002

出　　处：《自然灾害学报》2013年第5期104-111,共8页Journal of Natural Disasters

基　　金：中国地震局地震科技星火计划项目(XH12068)

摘　　要：水库诱发地震是影响水库安全和大坝稳定性的重要因素之一,对拟建大中型水库开展水库诱发地震专题研究是抗震设计的基础性工作之一。中波水电站位于青藏高原东南部的高山峡谷区,地层岩性以浅变质岩和沉积岩为主,玉曲河断裂基本沿库区左岸展布,为晚更新世活动断裂,并与闹中断裂交汇于库区中部。库区地震活动性在频度和强度上相对较低,但震级可达6级。库区有未来发生中强地震的构造背景和条件。在对库区地质环境条件进行调查研究的基础上,采用定性分析法和概率预测法分析,认为中波水电站存在水库诱发地震的可能性。采用水库综合要素法、逻辑信息法和灰色聚类法等方法综合研究表明,中波水电站水库诱发地震震级上限为4.5级,震中基本烈度上限为VII度弱,最有可能发生水库诱发地震的地段为中波—巴格库段。Reservoir induced earthquakes is one of the important factors to affect the reservoir safety and dam stability. Monographic study of reservoir induced earthquake is one of the basic work of the seismic design for planning-built medium and large reservoirs. Zhongbo hydropower station is located in the mountain gorge region in the southeast of Qinghai-Tibet Plateau. The formation lithology is mainly composed of low-grade metamorphic rocks and sedimentary rocks in the reservoir region. The Yuqu River fracture, which is a late Pleistocene active fracture, is basically distributed along the left bank of the reservoir. The Yuqu River fracture and the Naozhong fracture intersect in the central area of the reservoir. The frequency and intensity of seismic activity in the reservoir region is relatively weak, but the magnitude could be 6. In the reservoir region there is structural background and conditions for medium-strong earthquakes to occur in future. On the basis of survey and research on the geological environmental conditions of the reservoir region, and by using qualitative analysis method, probabilistic statistic method, logic information method and grey cluster method, the possibility, magnitude and intensity of reservoir induced earthquakes of the Zhongbo hydropower were forecasted. The results show that there is the possibility of the induced earthquakes, especially in the Zhongbo-Bage segment, the maximum magnitude of which could be 4.5 and the epicenter basic intensity could be less than Ⅶ.

关 键 词：水库诱发地震 震级 地震烈度 地震地质 西藏 

分 类 号：P315[天文地球—地震学]