The study of co-seismic response is one of the most direct and effective methods of revealing the stress and strain response law of the crust,which a key issues in Earth science.To some extent,the co-seismic response of groundwater temperature reflects the crustal deformation and ground vibrations caused by subsurface deformation,pores,or fissure changes,and vertical migration of groundwater.The 2008 Wenchuan(MS 8.0),2010Yushu(MS 7.1),and 2013Lushan(MS 7.0),and Minxian(MS 6.6)earthquakes had substantial impacts on subsurface fluids in the Chinese mainland;however,the co-seismic response characteristics caused by the four earthquakes differed significantly.The range,magnitude,and duration caused by the last three earthquakes were far lower than those of the Wenchuan earthquake.Although the response characteristics caused by the Yushu and Lushan earthquakes differed,they had essentially the same magnitude.The co-seismic effect caused by the Wenchuan earthquake was significantly higher than that of the other earthquakes.Although seismic responses were noted throughout the entire Chinese mainland after the Wenchuan earthquake,similar shock responses were detected mainly near the epicenters of the earthquakes.The co-seismic effects caused by the same-magnitude Yushu and Lushan earthquakes also differed.For example,the effect was observed in North China,central China,Sichuan,Yunnan,and Tibet after the Yushu earthquake;however,that of the Lushan earthquake was concentrated mainly near the epicenter in Sichuan,Yunnan,Chongqing,and other areas.Therefore,the influence of Yushu earthquake may be much larger than the Lushan earthquakes.The co-seismic amplitude of the Wenchuan earthquake was generally higher than that of the other three earthquakes;however,it was significantly higher near the epicenter of the earthquake.The depth of sensors in the well water had a very strong influence on co-seismic response because the co-seismic direction and magnitude differed when the water temperature sensor was placed at different depths in the same well.This phenomenon may be related to epicentral distance and magnitude and may be affected by the rupture mechanism and the stress and strain sensitive extent response to aquifer media of the observation points.