[关键词]
[摘要]
基于新10井水位对九寨沟MS7.0、精河MS6.6地震的同震响应特征,分别利用水震波和潮汐分析法,反演得到了新10井水位在地震波作用期间和地震波作用前后含水层参数特征,探讨了2次地震引起的新10井同震响应变化机理。结果表明,新10井水位对九寨沟地震和精河地震具有不同的同震响应形态,利用水平流模型反演所得的新10井含水层渗透系数,在九寨沟地震时为61m/d,而在精河地震时为147m/d,表明地震波作用导致水平向的渗透性增强;利用垂向流模型反演得到的新10井含水层渗透系数,在2次地震之前约为49×10-5 m/d,而在地震之后约为18×10-5 m/d,表明地震波作用导致垂直向的渗透性减弱。因此,新10井水位的同震响应变化与地震波引起的含水层渗透率的改变有关。
[Key word]
[Abstract]
Based on the co-seismic water level response followed by the Jiuzhaigou MS7.0 earthquake and the Jinghe MS6.6 in Xin Well 10, we obtained the hydrogeological parameters of Xin Well 10-aquifer system by tidal analysis and seismic wave analysis. The mechanism of co-seismic response of Xin Well 10 caused by the two earthquakes was discussed. Our main conclusions include:the water level of Xin Well 10 showed different co-seismic response to the Jiuzhaigou earthquake and the Jinghe earthquake. The hydraulic conductivity of Xin Well 10 aquifer obtained by horizontal flow model was 61m/d in the Jiuzhaigou earthquake and 147m/d in the Jinghe earthquake, indicating that the seismic wave led to the enhanced permeability in horizontal direction. The vertical hydraulic conductivity of aquifer in Xin Well 10 by using the vertical flow model was approximately 49×10-5m/d before the two earthquakes, and was about 18×10-5 m/d after the earthquake, showing that the earthquake caused vertical permeability decease. Therefore, the co-seismic response of water level in Xin Well 10 is related to the change of aquifer permeability caused by seismic wave.
[中图分类号]
P315
[基金项目]
国家自然科学基金资助项目(41502239)、中国地震局监测预测科研三结合课题(CEA-JC/3JH-163102)共同资助