The origin of hydrological responses following earthquakes in a confined aquifer: insight from water level, flow rate, and temperature observations

[摘要] Although many mechanisms of earthquake-inducedhydrological response have been proposed in recent decades, the origins ofthese responses remain enigmatic, and a quantitative understanding of them islacking. In this study, we quantitatively analyze the mechanism of coseismicresponse in water level and flow rate from an artesian well in southwesternChina before and after multiple earthquakes and reveal the origin of theearthquake-induced hydrological response based on the monitoring data ofwater temperature. Water level and temperature always show coseismicstep-like increases following earthquakes, which are independent of theearthquakes' epicentral distances and magnitudes. Tidal analysis findschanges in aquifer and aquitard permeability following these earthquakes,which corresponds to the post-seismic total discharge of 85–273 m 3 in 20 d after earthquakes. Furthermore, we couple the flowrate and temperature data to model the mixing processes that occurredfollowing each earthquake. The results indicate that coseismic temperaturechanges are the result of the mixing of different volumes of water fromshallow and deep aquifers, with the mixing ratio varying according to eachearthquake.

[学科分类] 妇产科学