汶川8.0级地震前地震空间相关长度变化特征

The changing Characteristics of Seismic Correlation Length before Wenchuan M8.0 Earthquake

摘要:

分析了汶川8.0级地震前的地震空间长度的时空演变。在计算空间相关长度过程中采用长轴与孕震区主要断裂走向一致的椭圆型空间窗,并设计了优化程序。在本次特大地震前观测到了增长的地震空间相关长度。利用合成地震目录对结果进行了显著性检验,结果否定了零假设,表明观察到的模型不是由随机数据干扰造成的,这一观点的置信水平被证实为93.9%。

Abstract:

The time-space evolution of seismic correlation length before Wenchuan M8.0 earthquake is analyzed.We use ellipse which long axis is coincident with the strike of main fault belt in source area as the spatial window in analyzing on growing correlation length,and design the corresponding optimization procedure.The result shows that the growing correlation length before Wenchuan earthquake could be observed,and the significance of result is tested by the random synthetic seismic catalog.The result rejects the null hypothesis for the catalog and shows that the observed patterns are not a consequence of random fluctuations,with 93.9% confidence levels.