用块体应变能预测强震位置与震级的研究

Study on Predicting Epicenter Location and Magnitude of Strong Earthquake in Geologic Block Using Strain Energy

综合地质构造、岩体力学性质、应力应变状态及其演化历史等各种因素将其统归为应变能积累特征对强震活动进行研究。对利用形变空间特征变化判断强震震源区位置的方法进行了讨论并确认其可行性,提出估算块体应变能的方法。由新构造划分块体边界、地壳测深确定底面进而确定块体体积、形变测量确定年平均应变速率、地壳速度构造确定弹性常数、历史强震确定能量积累起点(起始时间),由此估算块体积累总应变能,进而依据能量估算地震震级。最后以实例论述应变能积累特点对强震位置和震级预测的良好效果以及对地震安全性评价的重要意义。

Various factors such as geological structure,mechanics property of rock-mass,stress-strain state and its evolvement history etc. are boiled dow n to the characteristics of strain energy accumulation,and then the activity of strong earthquakes are studied. Firstly,we discussed the method which is used to judge the epicenter location of strong earthquake by spatial characteristic method of deformation and confirmed its feasibility,and proposed the method of estimating the strain energy in the geologic block. Secondly,on the basis of the block boundary is divided by new tectonic,the bottom is obtained by crustal sounding to determine the block volume,annual strain rate is achieved by deformation measurement,the elastic constant is acquired by crustal velocity structure,the energy accumulation point（ starting time） is determined by use of historical earthquakes,we confirmed the total accumulation strain energy of the block,and predicted the magnitude of the future earthquake. Finally,we discussed the good effect of the features of strain energy accumulation on predicting the location and magnitude of strong earthquakes,and the significant role in earthquake safety evaluation by real examples.