摘要
二滩水电站于1998年5月1日下闸蓄水,至今已有1年多。1年来,库首区周边出现了少量与库水位涨落有关的弱震活动。本文使用了二滩水库遥测地震台网的8个高增益子台、1个低增益子台共23道记录的地震分析资料。通过对蓄水前后发生地震比较,重点对1998年5月发生在龙胜乡的小震群,6月鱼干鱼乡西北的小震群及8月发生于大坝附近的小震序列进行了分析研究。探讨了1998年5月至1999年5月的水库水位变化与地震次数及震级大小的关系。由此,得出了二滩水库蓄水初期的地震活动性研究的初步结论:蓄水后数10亿吨库水的加载导致岩石形变附加剪切应力可能是导致初期水库周边弱震活动增加的诱发因素。笔者认为加强对大坝及周围地区的地震监测和对水库诱发地震的预测研究,减轻未来可能发生的构造型诱发地震灾害是下一阶段的首要任务。
It has been more that 1 year since it closed floodgate in 1,May 1998 in the Ertan hydroeleetric power station.It has appeared a small amounts of weak shake activities with fluctuat of the water level around the dam area of the reservoir.The earthquake records from the seismographs with totalled 23 traces including 8 high gain Son′s and 1 low gain Son′s stations in Ertan Selsmic Network are used in this paper.Comparing the information of the shakes before and after filling,2 small earthquake swarms which taken place in longshen in May in Ganyn in June and also a earthquake sequence in August,1998 Near the dam were studid.We studid the relations about rise and fall of the storewater level and times of shakes and dimonsion of the earthquake magnitude in the reservoir from May,1998 to May,1999.Then,through studing the earthquake activity just after filling,I have a initial conclusion:it is probably a guiding which leads to adding the weak shake activities around the reservoir in the initial stage of filling that increase the weight of several billion tons of storewater touches off additional shear stress of rock deformation in the reservoir.Author puts out that it is a most important task to give more research to the earthquake monitering and induced earthquakes in the dam area in the reservoir,and so mitigates the disasters of the teetinic induced earthquake in next stage.
出处
《地震地磁观测与研究》
2000年第1期12-21,共10页
Seismological and Geomagnetic Observation and Research
关键词
二滩水库
地震活动性
水库诱发地震
水库蓄水
Ertan reservoir,telemetric seismic network,seismicity,reservoir induced earthquake
