Coseismic response of water level in Xin10 well caused by M_S6.7 Akto, Xinjiang, earthquake

A hydroseismogram induced by the Akto M_S6.7 earthquake in Xinjiang on November 25, 2016 was recorded by digital high frequency sampling level gauge. We comparatively analyzed the correlation characteristics between the water level and the vertical ground motion, and the relationship between the above two and the hydrological parameters of well-aquifer system was carried out by a thorough discussion. The results suggested that: ① similar to the seismic signal, there are two significant periods, 6--10 s and 15--30 s in the hydroseismogram of Xin10 well induced by the Akto M_S6.7 earthquake. ② overall, the response amplitude of hydroseismogram in Xin10 well was positively correlated to the amplitude of vertical ground motion, and the amplitude ratio of the two increased with the reduction in frequency at high frequency (greater than 0.08 Hz), which indicated that the water level of Xin10 well could enlarge signals with period more than 12 s more effectively. ③ permeability coefficient of Xin10 well-aquifer system was estimated at about 10^-2 cm/s by using the amplitude ratio of the hydroseismogram and seismic waves, and the hydrogeological parameters in aquifer also fluctuated during the process of seismic wave action. The results in this paper also showed that the coseismic response mechanism of well water level is more complicated, and high sampling rate of water level data is the guarantee to obtain reliable results and knowledge in coseismic response of water level analysis.