【摘要】 基于1970年以来辽宁地区7次5级以上地震,分别从震前中小地震活动图像和时序扫描的角度,对历次地震前的地震学指标进行了系统梳理和提炼,结果显示:空区、条带、b值、A(b)值、D值、缺震及XY值对辽宁地区5级地震的映震效果较好。因此结合以往关于辽宁地区中等地震集中增强和震群特征的研究结果,综合起来初步将其构建为辽宁地区5级地震的地震学指标体系。其中强度预测指标主要有中等地震集中增强、震群序列、条带和空区,未来主震最大震级估算方法为上述四种情况中的最大地震震级加1.5~2.0;地点预测指标与强度指标相同,判定方法是未来5级地震通常位于条带上和空区边缘及其附近地区,若有中等地震集中增强活动,则未来5级地震靠近最近一次中等地震的位置,若出现震群序列,则未来主震发生地点为震群周围200km(前震序列时,主震就发生在序列原地附近);时间预测指标除了强度和地点指标中的4项外,还包括b值、A(b)值、D值、缺震和XY值,总体看来后三者异常通常出现在震前的一年左右,空区和条带的解体时间以及b值异常通常出现在震前的半年左右,前震序列开始时间距离主震发生通常在1~20天左右。更多还原

【Abstract】 The seismological prediction indexes of seven earthquakes(M ≥5.0)occurring in Liaoning since 1970 were analyzed from medium-small seismicity images and sequential scanning.Results show that the earthquake-reflecting effect of certain parameters,i.e.seismic gap,seismic belt,b value,A(b)value,D value,earthquake deficiency,and XYvalue is relatively good.Combining previous results of enhancements,concentration of moderate earthquakes,and characteristics of earthquake swarms in Liaoning,a seismological index system of earthquakes with a magnitude of M ≥5.0was constructed.Earthquake intensity prediction indexes mainly include the enhancement and concentration of moderate earthquakes,earthquake swarm sequences,seismic gaps,and belts,and the maximum magnitude of a forthcoming main shock is estimated by adding 1.5~2to the value of the maximum magnitude of the earthquake for the above four items.The location prediction index is similar to the earthquake intensity prediction index,and the method determined shows the following:earthquakes with a magnitude of M ≥5.0generally occur in the seismic gap and belt or nearby region;if there is an increase and concentration in moderate earthquakes the location of forthcoming earthquakes with M ≥5will be close to where the last moderate earthquake occurred;if there is an earthquake swarm sequence,the forthcoming main shock will occur within 200 km of the swarm(if there is a foreshock sequence,the main shock will occur near the location of the sequence).In addition to the four items used in earthquake intensity and location prediction indexes,the seismic time prediction indexes include the b value,A(b)value,D value,earthquake deficiency,and the XYvalue.Furthermore,the anomalies of A(b)value,D value,earthquake deficiency,and XYvalue commonly occur about one year before the earthquake;disappearance of the seismic belt and seismic gap,and b value anomalies commonly occur about half a year before an earthquake;and the foreshock sequence commonly occurs about 1to 20 days before the main shock.更多还原