Comment on hess-2022-326

Abstract

Although many mechanisms of earthquake-induced hydrological response have been proposed in recent decades, the origins of these responses remain enigmatic and a quantitative understanding of them is lacking. In this study, we quantitatively analyzed water level, flow rate, and water temperature data from an artesian well in southwestern China before and after multiple earthquakes. Water level and temperature always showed co-seismic step-like increases following earthquakes, which were independent of the earthquakes’ epicentral distances and magnitudes. Tidal analysis found changes in aquifer and aquitard permeability following these earthquakes, which correspond to the post-seismic discharge of 85~273 m3. Furthermore, we coupled the flow rate and temperature data to model the mixing processes that occurred following each earthquake. The results indicate that co-seismic temperature changes are the result of the mixing of different volumes of water from shallow and deep aquifers, with the mixing ratio varying according to each earthquake.