论文部分内容阅读
分析了1975年2月4目辽宁海城地震后的熊岳、1976年4月6日内蒙和林格尔地震后的凉城、以及1976年7月28日唐山大震后的宝坻等震群活动的时空分布特点.由位错模式计算了大地震在相应地区产生的附加应力(张应力)的大小(3—6巴),它和由这些震群中的小地震计算的应力降的大小相当.附加的张性应力相当于减小围压.根据不同应力途径的三轴压缩实验以及原地庄水诱发地震的试验结果指出,上述量级的应力变化可以在地壳浅处应力水平已经很高的地区触发地震活动.考虑到地下流体的扩散特性及其作用,初步解释了震群活动的高潮滞后大地震的观测事实,从而引出了大地震对其附近的震群活动的一种可能的触发机制.
Xiong Yue, the head of 4-head Liaoning Haicheng earthquake in February 1975, Liangcheng after Inner Mongolia and Ringer Earthquake on April 6, 1976, and the Baojuan earthquake swarm after the Tangshan earthquake on July 28, 1976 The spatial and temporal distribution of the earthquakes.The magnitude of the additional stress (tensile stress) (3-6 bar) produced by the large earthquakes in the corresponding area was calculated by the dislocation model and the magnitude of the stress drop calculated by the small earthquakes in these swarms The additional tensile stress is equivalent to reducing the confining pressure.According to the triaxial compression experiment of different stress paths and the test results of in-situ water-induced earthquakes, it is pointed out that the above-mentioned stress changes in the shallow crustal stress level have been very High region triggers the seismic activity.According to the diffusion characteristics of subsurface fluid and its function, this paper initially explains the fact that the climax of the swarm activity lags behind the observation of the large earthquakes and leads to a possible earthquake response to the earthquake swarm near it Trigger mechanism.