四川地震震级与烈度区面积和震源深度的关系

The Relationship Between The Earthquake Magnitude And The Area of Earthquake Intensity,The Depth Of Earthquake Origin In Sichuan

本文按照地震地质分区,同时考虑7级以上地震的空间分布特征,分四川为鲜水河、松潘—龙门山及马边地震带等几个区带,对四川1900年以来既有仪器测定参数、又有宏观烈度考查的33个地震资料,应用多元线性回归分析方法,统计拟合出了震级与不同烈度区面积、烈度值、震源深度之间的多组关系式,其一般形式为:■相关系数R大都在0.90左右,用部分地震检验的结果表明,震级误差一般小于0.3,震源深度误差一般小于5公里,基本消除了离散情况,笔者用求得的关系式对1900年以前的有三条以上等震线的部分历史地震的震级、震源深度进行了标定,结果也比较令人满意。

According to seismogeological region and thinking about the space distribution feature of the earthquake more than-magnitude7, we divide the area of Sichuan into three belts—the Xianshuihe,the Songpan—Longmen mountain and the Mabian—in this paper. We analysed the data of 33 earthquakes since 1900 that include the instrument detemining parameters and macrointensity survey parameters. We made a statistic analysis and fit many groups relation formula between the earthquake magnitude and the area of different intensity region, the intenity value,the depth of earthquake origin with the analysis method of multivariate linear regression. The general formula is: M=a+Σb_I(logIA_T)^(1/2)+C log h All correlation coefficients are about 0.90. We tested some earthquakes with above formula. The testing result shows that the error for the earthquake magnitude is usually less than 0.3 and the error of the depth of earthquake origin is usually less thean 5 kilometer. We tested the hisorical earthquakes occurred before 1900 with the relation formula obtained by us. There are more than 3 isoseismal curves in the earthquake areas. The testing results are also satisfactory.