云南地区地震活动的有序迁移图像  

SEQUENTIAL MIGRATION PATTERN OF SEISMICITY IN YUNNAN REGION

作　　者：蔡静观[1] 李永莉[1] 刘丽芳[1] 许昭永[1] 秦嘉政[1] 苏有锦[1] 付虹[1] 

机构地区：[1]云南省地震局,昆明650041

出　　处：《地震地质》2002年第3期335-345,共11页Seismology and Geology

基　　金：国家重点基础研究发展规划项目 (95 130 5 0 5 );中国地震局双重项目 (96 9130 90 2 0 30 1)共同资助

摘　　要：重点追踪了云南地区中强震的动态图像 ,发现在云南地区强震活跃期前 1～ 4a出现中强震的有序迁移 ,有序迁移的中强震预示了活跃期强震时空分布的总体格局 ,80 %的强震发生在这些中强震 15 0km范围内。有序迁移结束后 2d至 11个月发生活跃期的首次强震 ,其中 75 %在 3个月内。文中介绍了强震的等间距迁移、强震活跃期后期中强震的有序迁移 ,巨震前后大震的有序迁移和中等地震的定向迁移与部分震例 ,但地震活动有序迁移图像的机理尚待研究。The dynamic pattern of moderate strong earthquakes in Yunnan region has been traced in this paper. It is discovered that a sequential migration of moderate strong earthquakes occurs 1～4 years before the active period of strong earthquakes in Yunnan region; the sequentially migrated moderate strong earthquakes indicate the general layout of M ≥6.7 strong earthquakes during the active period, while about 80% of the strong earthquakes occur within a range of 150km from the epicenters of these moderate strong earthquakes. The first strong earthquake of the active period occurs within 2 days to 11 months after the termination of sequential migration of moderate strong earthquakes, and about 75% of the first strong earthquakes occur within 3 months. During the active periods Ⅰ and Ⅲ in Yunnan region, 8 of 10 strong earthquakes occur within the range of 190km from the apexes of tetragon formed by linking the sequentially migrated epicenters of moderate strong earthquakes (such as the epicenters of Huaning, Ludian, Jianchuan, Longling, Qiaojia, and Jinning earthquakes, as well as those of the Jiangcheng, Ruili, Zhongdian, Yongshan, and Jinghong earthquakes), while about 60% of the strong earthquakes occur within a range of 50～90km from the epicenter locations of moderate strong earthquakes. The M 7.7 Tonghai earthquake of January 5, 1970 occurred on the eastern side of the tetragon mentioned above, showing an equidistant layout of 230km from Yongshan in the north to Dongchuan, Tonghai and Jiangcheng in the south. The relationship between sequential migration of moderate strong earthquake and the occurrence of strong earthquake for the active periods Ⅱ and Ⅳ has a little difference from that for the periods Ⅰ and Ⅲ. Sequential migrations of moderate strong earthquakes from Lancang to Lufeng, Shiping and Tengchong, as well as from Shidian to Ninglang, Huidong and Lancang make up tetragons, while the strong earthquakes occur at the starting or ending positions of the migration,

关 键 词：云南地区 地震活动 有序迁移图像 时空分布 定向迁移 

分 类 号：P315.5[天文地球—地震学]