塔里木盆地库车坳陷北部边缘与南天山过渡带结构复杂,是了解塔里木盆地-南天山盆山关系的关键.利用2D、3D地震资料和钻井资料,分析塔里木盆地库车坳陷北部边缘的结构特征、构造样式,对比研究不同区段变形的差异和影响构造样式的主要因素.研究结果表明:①根据基底断裂的发育情况,库车坳陷北部边缘自北向南可划分为三区五带,自浅至深可划分为4个变形层.其中,山前克拉苏构造带以克拉苏断裂为界可细化为高角度基底卷入变形区、低角度基底卷入变形区和盖层滑脱变形区.②库车坳陷盆山过渡带主要发育收缩构造、盐构造和走滑构造,根据其表现形式可划分为15种样式.③库车坳陷北部克拉苏构造带可划分为6个主要的构造段,受先存基底断裂、膏盐岩分布和南天山差异推覆作用的影响,各构造段表现出差异变形的特征.④现今构造主要形成于新生代中晚期,经历了晚二叠世-三叠纪古前陆盆地、侏罗纪-白垩纪坳陷盆地、古近纪-中新世弱收缩挠曲盆地和上新世-第四纪陆内前陆盆地4个演化阶段.%The transition zone between Kuqa depression and South Tianshan uplift located in northern Tarim basin has complex structural system. This area is the key to understand the relationship between mountains and basins. Based on the newly-obtained 2D,3D seismic and drilling data,the authors studied the basin structure, structural styles and deformations in various segments. Some conclusions have been reached:①The transition belt between Kuqa depression and southern Tianshan uplift can be divided into five belts and three districts from north to south and four layers in vertical direction. The Kelasu belt can be divided into three deformation zones, i, e., high angle basement involvement zone, low angle basement involvement zone and cover rock decollement zone.②The transition belt mainly formed three styles of structures, namely contraction structural style, salt structural style and strike-slip style. ③Kelasu belt can be divided into six segments form east to west with each segment having its own deformation style.④The present structure feature was mainly formed in Late Cenozoic. The structural evolution stage can be divided into four stages, i.e., Late Permian-Triassic paleo foreland basin, Jurassic-Cretaceous depressive basin, Paleogene-Miocene weak contraction flexure basin and Pliocene-Quaternary intra-continent foreland basin. Pre-existent structure, salt flow and various thrusting nappes constituted main factors responsible for differential deformation.
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