Research Of Simulation The Dynamic Environment Of Groundwater Of The M=7.8 TangShan Earthquake

On July 28, 1976, a great earthquake with Richter magnitude 7.8 occurred in TangShan of HeBei province, During the quake time of 30 to 60 seconds, more than 242,000 lives were killed in sound sleep, over 164,000 people were injured, the property loses over 1,250,000,000 dollars . It is the most destructive earthquake in the past hundred years in China. The people of the past have complete research already about the groundwater behaviors of the M=7.8 TangShan earthquake. Now a research of the permeate flow field of groundwater to have no to start completely.We were according to the coupling theory between osmotic flow field of groundwater and stress field, foundation a hydrology Model of tectonic activities background in BeiJing, TianJin and TangShan area. Adoption finite-difference simulation identifies abnormal information of the M=7.8 TangShan earthquake. Base on the response of well-aquifer systems to stress condition, inversion stress field of preceding and following an earthquake. The following are some productions we have gained from the study:Using tide of well-water level observation data in near sea zone,through the oceanic tide loading correction,we have gained productions logical from add a parameter that tidal gravitation wave to influence aquifer permeability, improved on the method who Hsieh and Bredehoeft avail earth tide effect calculation hydrology parameter of aquifer.Regard numerical simulation results as background osmotic flow field, hypotheses no other than G-force influence in osmotic flow field of groundwater. The results show that exist prominence difference between simulation and actual measurement from 1974 to 1976, the "difference" was hard of explanation groundwater equipoise theory. Pilot studied thought, it may be a result that influence of regional stress field.A study relationship between exploitation pump water and groundwater level wave in North China, we have gained a method which quantificationally elimination pump influencing factor of water-level wave. The groundwater level trend to descend quickly near the epicenter before the TangShan earthquake from 1972 to 1975, is it to exploit an influence of groundwater or an earthquake abnormality? This problem is quantified study. We were according to the response of well-aquifer systems to solid tidal, ascertained stress response coefficient of aquifer. The results show that the stress response coefficient in a position to reflect lithology and configuration of aquifer.Through the study relationship of spatial-temporal evolution between dynamic environments (stress field) and seismic activity, the results show that the principal compressive stress axis turn about 90°, when the medium earthquakes increase, the strain release being accelerated, the b-value curve fell-off and the gap being formed. It was emblematize that the strong shock was pregnant with transition from medium term to medium-short term (one year more or less). In medium-short term stage, the stress field more increase, the medium earthquakes quietude, the strain release curve become flat after being accelerated, seismicity gap disorganization and Shrinkage become short-term gap. In short-term stage, the stress field becomes weak and contractive towards the centre of epicenter area, the seismic activity near the epicenter quietude, ambient the medium-small Earthquakes increase. After the strong shock occured, the hypocenter burst and expansive action vanish, the principal compressive stress axis recovery.