英吉苏凹陷中—新生代构造特征及成因机制

Structural characteristics and genetic mechanism of the Meso-Cenozoic Yingji su piggyback foreland basin

英吉苏中新生代凹陷是在古生代斜冲推覆构造背景之上发育起来的背驮式前陆盆地。盆地的沉积作用和变形作用严格受基底参与的斜冲断层的控制。中新生代构造由北向南可划分7个带:北部斜坡带;群克—新开屏背斜带;英北向斜带;阿拉干背斜带;英南向斜带;古城墟斜坡带和罗布庄断凸带。叠瓦式逆冲断层、花状构造、构造三角带、断展褶皱和披覆构造是英吉苏凹陷的主要变形样式。自三叠纪以来,不同时期的沉积中心自造山带向前陆方向迁移。中新生界变形的动力学和运动学是与塔里木板块南缘活动大陆边缘的板块拼贴事件和壳内拆离缩短作用有关。

The Meso-Cenozoic Yingjisu depression is a piggyback foreland ba si n developed in the setting of the Paleozoic thrust nappe structure.The sedimenta tion and deformation of the basin is strictly controlled by thrusts.From north t o south the Meso-Cenozoic structure may be divided into seven belts:the northern slope belt,Qongkol-Xinkaiping anticlinal belt,northern Yingjisu synclinal belt, Alagan anticlinal belt,southern Yingjisu synclinal belt,Guchengxu slope belt and Luobuzhuang fault rise.The imbricate thrusts,upthrust structure,struc-tural triangle zones,fault-propagating folds and drape structure are the mai n deformation styles of the Yingjisu depression.Since the Triassic,the depocente rs in different epochs migrated from the orogenic belt to the foreland.The Meso-Cenozoic deformation dynamics and kinematics are related to the amalgamation of plates on the active continental margin of the southern Tarim plate margin and i ntracrustal detachment-shortening.