高烈度区的水库地震问题

The reservoir induced earthquake problem in the high intensity area

本文提出重视我国中西部高烈度区水库地震问题的基础研究,即水库水域区位于历史地震影响烈度或地震区划在Ⅶ度及以上区域的水库地震问题。这些区域的水库地震研究,不能简单套用一般低烈度区水库诱发地震的一些技术思路和方法,而是需要研究高烈度区水库地震问题的特殊性,主要体现在库区构造环境、断裂活动、随机性背景地震活动水平高等特点。研究水库地震评价问题,包括水库地震强度的预测问题。用金沙江下游梯级水库地震研究事例试图说明这一点。分析水库地震问题,首要抓住在工程设计寿命期间构造地震的潜在危险性这一关键问题。水库地震研究中一些常见的统计预测不合理,应分析水库地震或诱发地震活动需要考虑的地震构造条件、库区岩性条件、地下应力条件、应变积累势态等。

This paper proposes that one should pay attention to the basic research of res- ervoir induced earthquakes in the high intensity area in mid-western China, namely the earth- quakes induced by the reservoir located in the area where the intensity of historical earth- quake or seismic regionalization up to , degree. To study the reservoir induced earthquake of these areas, the technical ideas and methods generally developed for the area with low intensity should not be simply copied. The particularity of reservoir induced earthquake in high intensity area must be studied, and it is embodied in the structural environment, faul- ting activities of the reservoir region and the high level of random background seismicity. The evaluation of reservoir earthquake includes the prediction problem of reservoir earth- quake intensity. To illustrate this point, we analyze the reservoir induced earthquake of Jin- sha river downstream cascade reservoir. To analyze the reservoir induced earthquake, it is the first of all to consider the potential dangers of tectonic earthquake during the engineering design life. Some common method such as statistical predition in the study of reservoir in- duced earthquake is not reasonable, the conditions of earthquake structure, reservoir litholo- gy, the underground stress and the strain accumulation tendency should be considered.