使用因子分析方法研究九江5.7级地震前的地震活动异常

使用2005年11月26日江西九江5.7级地震前震中附近地区的地震资料, 选择反映地震活动时、 空、 强特征的地震频次N(M_L≥3.0)、 b值、 η值、 A(b)值、 Mf值、 Ac值、 C值和D值参量进行因子分析。 这些参量之间具有一定的相关性, 各参量在不同时段的变化各有所异, 预报效果并不理想。 但是根据因子分析可以得到反映地震活动时、 空、 强特征的综合指标W_fa值, 该指标在九江5.7级地震前出现明显的异常变化。 表明综合指标W_fa值可以较好地反映地震活动的异常特征。 文中还对与因子分析结果的有关问题进行了讨论。

Research on anomalous seismicity before Jiujiang Earthquake with MS5.7 by using factor analysis method

Based on the earthquake data around the epicenter before the Jiujiang earthquake with M_S5.7 occurred on Nov. 26, 2005 in Jiangxi province, the factor analysis method is applied to select the seismicity parameters of earthquake frequency N(M_L≥3.0), b-value, η-value, A(b)-value, Mf-value, Ac-value, C-value and D-value that reflect seismicity characteristics of time, space and magnitude in this paper. There is a certain correlation among these parameters. The variation of these parameters is different, and the anomaly of many parameters is not obvious before Jiujiang earthquake. The synthetic parameter W_fa-value reflected the seismicity characteristics of time, space and magnitude shows obvious anomaly. It shows that the synthetic parameter W_fa-value can reflect anomaly characteristics of seismicity. The other problems of the factor analysis method and conclusion are discussed in this paper.