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在水平层状含水层(一维)模式下,根据含水层应力与井水位变化之间的定量关系表达式,利用华北地区40多口深井水位动态变化资料,探索研究华北地区现今构造应力场状态。即水位上升代表构造应力场压性增强张性减弱;水位下降代表构造应力场压性减弱张性增强。初步研究结果表明,1995～1998年华北北部地区张家口 渤海构造带和山西构造带北部水位普遍上升,MS5.0以上地震活动频繁;1999年以后华北地区水位普遍处于下降状态,反映了华北地区1999年以来构造应力场状态以张性为主,整个华北地区MS5.0以上地震活动处于相对平静状态。该结果可为华北地区地震活动性预测研究提供应力场背景信息。
According to the expression of quantitative relation between the stress of aquifer and the variation of well water level in horizontal layered aquifer (one-dimensional) mode, the dynamic changes of water level in more than 40 deep wells in North China are explored to study the current state of tectonic stress field in North China . That is, the rise of water level indicates that the tectonic stress field enhances the stress relaxation and the water stress decreases, which means that the tectonic stress field weakens and tensions weaken. The preliminary results show that the water level of Zhangjiakou Bohai Sea structural belt and the northern part of Shanxi tectonic belt in north of North China from 1995 to 1998 generally rise, and the earthquakes above MS5.0 are frequent. The water level in North China is generally declining since 1999, reflecting the fact that the water level in North China in 1999 Since the tectonic stress field is dominated by tension, the earthquakes above MS5.0 in North China are in a relatively calm state. This result can provide background information of stress field for seismic activity prediction in North China.