Correlation between movement of tectonicblocks and earthquakes in groups  

作　　者：范俊喜[1] 马瑾[1] 刁桂苓[2] 单新建[1] 

机构地区：[1]中国地震局地质研究所 [2]河北省地震局

出　　处：《地震学报》2001年第5期514-522,共9页Acta Seismologica Sinica

基　　金：Foundation item: State Key Basic Research Planning Project (G199804070401).

摘　　要：The Chinese mainland is divided into some tectonic blocks by nearly NE- and EW-orientated faults. Meanwhile strong earthquakes in the Chinese mainland usually cluster in time and space. We call earthquakes in groups. Tectonic blocks separated by faults and earthquakes in groups are prominent features of the tectonics of the Chi-nese mainland. Correlation between movement of tectonic blocks and groups of earthquakes is discussed in this paper. The results show that earthquakes in groups often occurred at one or several block boundary faults. The released elastic strain energy is built up in the same periods and around blocks. It means that strong earthquakes in groups are mainly caused by movement of blocks. Four types of block movement are identified based ongroup earthquakes: movement along a single boundary of a block (or a combined blocks), movement of a single block, movement of multi-blocks, and movement in block interiors. If we consider distribution of all strong earthquakes occurred in the Chinese mainland, the movement along a single boundary of a block is more popular one inducing strong earthquakes. But if we only consider earthquakes in groups rather than single earthquakesthe movement of a block dominates among four modes. Statistics with respect to group earthquakes show that the Taihangshan mountain and the North China block are much active in the eastern part of Chinese mainland, and in western part of Chinese mainland the active blocks are Sichuan-Yunnan and the Kunlun-Songpan ones.The China continent is divided into some tectonic blocks by nearly NE-and EW- orientated faults. Meanwhile strong earthquakes in the China continent usually c luster in ti me and space. We call 'earthquakes in groups'. Tectonic blocks separated by fa ul ts and earthquakes in groups are prominent features of the tectonics of the Chin a continent. Correlation between movement of tectonic blocks and groups of earth quakes is discussed in this paper. The results show that earthquakes in groups o ften occurred at one or several block boundary faults. The released elastic stra in energy is built up in the same periods and around blocks. It means that stron g e arthquakes in groups are mainly caused by movement of blocks. Four types of bloc k movement are identified based on group earthquakes: movement along a single b oundary of a block (or a combined blocks), movement of a single block, movement of multi-blocks, and movement in block interiors. If we consider distribution o f all strong earthquakes occurred in the China continent, the movement along a si ngle boundary of a block is more popular one inducing strong earthquakes. But if we only consider earthquakes in groups rather than single earthquakes, the move ment of a block dominates among four modes. Statistics with respect to group ear thqu akes shows that the Taihang Mountain and the North China block are much active i n the eastern China continent, and in western China continent the active blocks are the Sichuan-Yunnan and the Kunlun-Songpan ones.

关 键 词：成组地震 地块活动方式 中国大陆 地震构造 地震活动 断层 

分 类 号：P315.2[天文地球—地震学]