重庆井网水位水温同震响应特征分析

本文以2008年以来全球范围内发生的5次大地震为例,对重庆井网水位和水温同震响应特征进行了分析,结合井孔水文地质条件和自身观测条件,探讨了不同同震响应现象的可能成因并对其机理进行了探讨。结果表明,水位的记震能力优于水温,水位同震响应形态主要包括上升、下降和振荡三种类型,且同一口井水位对不同地震的响应形态不同;水温的同震响应形态主要包括上升和下降两种类型,其中只有荣昌华江和北碚柳荫井水温对5次地震均有同震响应,且同一口井水温对不同地震的响应形态相同。进一步分析表明,北碚柳荫井水位的同震响应能力优于荣昌华江井水位,北碚柳荫井水位的同震振幅与地震能密度成正比,并给出了其同震变化幅度与地震能量密度的对应关系。最后分别对水位和水温同震响应机理进行了探讨。

Characteristics of Coseismic Responses Groundwater Level and Temperature of Chongqing Well-Net

Taking five strong earthquakes occurred worldwide since 2008 as examples, we analyzed the coseismic response of Chongqing groundwater level and temperature. Combined wellbore hydrogeological conditions and its own observation conditions, we explored the possible causes of different phenomena with coseismic response and possible mechanism. The results show that groundwater level is more sensitive to earthquake than the temperature, and the main coseismic change for groundwater level includes three types of rise, fall and oscillation. For a single well, the response features vary with different earthquakes. The main coseismic change for groundwater temperature includes two types of rise and fall. The Huajiang well in Rongchang and the Liuyin well in Beibei have coseismic response to 5 earthquakes, and for each well, the response features are consistently to different earthquakes. Further analysis indicates that the groundwater level of Huajiang well in Rongchang is more sensitive to earthquake than the Liuyin well in Beibei. The amplitude of coseismic groundwater level of Liuyin well in Beibei is proportional to the seismic energy density, and shows the corresponding changes in their relationship with the magnitude of the earthquake and the seismic energy density. Finally, we analyzed the mechanism of groundwater level and temperature.