用b值横截距预报强余震震级的方法探讨

DICUSSION OF THE PREDICTION METHOD FOR MAGNITUDE OF STRONG AFTERSHOCK WITH THE CROSSCUT WAY OF b - VALUE

本文在G-R(logN=α—M)关系的基础上,探讨用b值横截距法预报地震序列强余震的震级。选用我国1966—1986年21年内有完整资料的58个Ms≥5.0地震序列,用b值横截距法进行预报检验。这些地震序列的位置分布较广,遍及全国各大区,而且要求每个地震序列满足震级M≥Mo(起始震级)的地震个数不少于50个。统计结果表明,对预报序列中强余震的吻合率为93％以上。另外,我们还用b值横截距法对序列的晚期强余震预测及在主震后尽可能短的时间内预测强余震进行了探索,表明它是可能的。

Based on the Gutenberg-Richter relation log N = a - bM, prediction for magnitude of strong aftershock is dicussed by using crosscut method of 6 -value. We choose earthquake sequences which have complete data and the maximum magnitude MS is bigger than and equal to 5. 0 in 21 years from 1966 - 1986, to examine the predictions using the crosscut method of 6 -value. The location of the 58 selected sequences is widely distributed, covering every big district in China, and the number of earthquakes (M≥M0) is not less than 50 in each sequence. Satistical results show that the success rate of prediction of strong aftershock is above 93%. Possibility of prediction of late strong aftershock and prediction of strong aftershock as soon as possible after the main shock by using crosscut method of 6-value is also investigaged in the paper. The rusults show that it is also useful in earthquake prediction.