湘东地区断裂活动性及潜在震源区划分研究

湘东地区(湖南省东部地区)地处华南褶皱系内,经历了多次构造运动,地层普遍褶皱,并伴有一系列NNE—NE向断裂,沿这些断裂形成一些断陷盆地;新构造运动期间,地壳运动以大面积整体性缓慢抬升为主要形式,差异性构造活动较弱,但该区发生了多次中强地震,断裂在第四纪早、中期有活动可能与中强地震的发生有关。文中在收集、分析研究区及附近地区前人工作成果的基础上,对常德-益阳-长沙断裂东南段、湘潭-邵东断裂东北段和永州-衡阳断裂开展了地质学、地貌学的野外考察,综合分析了这些断裂第四纪早、中更新世以来的活动性。采用"地震重复"和"构造类比"2条基本原则,依据特定地段的地质、地震和地球物理场等资料,认为这些断裂带不但具有中更新世活动形迹,而且沿带存在中强地震的潜在危险。综合社会和经济发展的需求等因素,将湘潭—湘乡、邵东、衡山—衡阳、永州等地带划分为新的潜在震源区

FAULT ACTIVITY AND DELINEATION OF THE POTENTIAL SEISMIC SOURCES IN HUNAN

Located in the south China fold system,the eastern Hunan area has experienced several tectonic movements,which resulted in wide-spread distribution of folds accompanied by a series of NNE-NE trending faults,and some rift basins were developed along these faults. During the neotectonic movement,the crustal movement was dominated by large-scale and overall slow uplift with weak differential tectonic movement. However,this area has experienced a number of strong earthquakes,which are supposed to be related to