【摘要】 上扬子地区褶皱-冲断带的运动学特征一直缺乏系统研究。在前人基础上,结合野外认识、地震地质剖面解释、构造活动定年等相关成果分析认为,上扬子地区印支期以来至少存在着3组不同方向的区域挤压应力。其中,NW-SE向挤压应力具印支期、燕山期与喜马拉雅期多期活动特点,近SN向挤压应力主要在燕山晚期,NE-SW向挤压作用主要发生在喜马拉雅期。由此所形成的造山带至前陆褶皱-冲断带的运动学结构模式存在较大差异,即龙门山造山带发育了较为典型的根带、中带、锋带与外缘带等复杂的逆冲推覆构造系统,米仓山与南大巴山造山带缺乏中带变形的特征,雪峰山陆内前陆盆地系统则表现为逆冲的锋带在倾向上传播距离长、在走向上影响范围大等特点。上扬子地区褶皱-冲断带的运动学特征控制了不同时期油气的运移方向及聚集场所。更多还原

【Abstract】 There are little systematic researches on the kinematics of the fold-thrust zones in the western Yangtze Area.In this paper,based on preview papers,field surveys,geological explanation of seismic reflection profile and tectonic dating,the kinematics of the fold-thrust zones in the western Yangtze Area has been studied elaborately.The results show that there are at least three different regional stress-fields in the western Yangtze Area since the Indosinian Epoch,i.e.compressions with the NW-SE direction,the SN direction and the NE-SW direction.Among them,the compression with NW-SE direction occurred several times at the Late Indosinian stage,at the Early Yanshan stage and at the Late Yanshan-Himalaya stage;the compression with SN direction mainly happened at the Late Yanshan stage;and the compression with NE-SW direction,leading to intensive deformation within interior basin,mainly occurred at the Late Himalaya stage.Moreover,the kinematics models from orogenic belt to foreland fold-thrust zone have been analyzed in four structural provinces in the western Yangtze Area.The Longmenshan orogenic belt holds the typical characteristic of a complex thrust-nappe system consisting of a root-belt,a middle-belt,a front-belt and an outside-belt.The Michangshan and Dabashan orogenic belts lack the middle-belts;and the Xuefengshan intra-continental foreland basin system has the deformation characteristics that the front-faults have propagated for a long distance in the direction of dip and affected for a large scale in the direction of strike.The characteristics of the kinematics of the fold-thrust zones determined the petroleum’s moving-directions and gathering places in the western Yangtze Area.更多还原