【摘要】 利用近震直达Pg波和Sg波垂直向最大振幅比方法,求出安徽及周边地区1974年以来246次ML2.0级以上地震的震源机制解。采用系统聚类方法,得到安徽不同分区不同时段的震源机制优势综合解,分析不同分区构造应力场的特点。对安徽地区中小震震源机制解中应力轴参数进行统计分析表明,其优势方向与华东地区构造应力场方向基本相同。研究安徽地区震源机制一致性参数特征发现,在中强震发生前,一致性参数均出现显著下降。更多还原

【Abstract】 246 focal mechanism solutions of ML≥2.0 earthquakes in Anhui and adjacent areas since 1974 are calculated using maximal vertical amplitude ratio of Pg and Sg.By using system clustering method,preponderant composite focal mechanism solutions of each subarea in different period is calculated to analyze the characteristic of regional stress field in each subarea.Statistic analysis of stress axes parameters shows that the predominant direction is approximate to the stress field direction in East China.The coherence parameter of focal mechanism solutions in Anhui Area drops obviously before mid-strong earthquakes.更多还原