玉树地震前不同空间范围内地震活动分布特征研究

Distribution Characteristics of the Multi-scale Spatial Seismic Activities before the 2010 M7.1 Yushu Earthquake

北京时间2010年4月14日7时49分青海省玉树藏族自治州玉树县发生7.1级地震。本文利用Kolmogorow-Smirnov分布检验法,对玉树地区不同空间范围内1995—2010年小震月频次分布进行了检验,得到玉树周边地区不同空间范围内小震月频次不服从正态分布和泊松分布,并根据峰度、偏度、标准差σ、CV值以及bm等统计参数,对玉树周边不同空间范围内小震活动分布特征的时间变化进行了进一步分析。结果显示,在玉树地震前,不同空间范围内小震月频次的峰度、偏度、标准差σ、CV值以及bm等均表现出明显的异常变化。

At Beijing time 7：49 on April 14,2010,an earthquake of magnitude 7.1 occurred in Yushu county,Tibetan autonomous prefecture in Qinghai Province.In this paper,the Kolmogorow-Smirnov distribution test method has been used to test the distribution of the monthly number of small earthquakes on multi-scale.It was found that this number is neither normal distribution nor Possion distribution.According to computed values of kurtosis,skewness,standard deviation,the value of CV and some other statistical parameters,for example the bm parameter,we also analyzed the time variation of the monthly number distribution of small earthquakes before the the 2010 M7.1 Yushu Earthquake.