塔里木盆地巴楚断隆中新生代的构造演化

The Meso-Cenozoic Evolution of Bachu Fault-Uplift in Tarim Basin

巴楚断隆的形态、成因及边界断裂与其南北两侧前陆凹陷的形成戚息相关。在印度板块向欧亚板块俯冲的大背景下 ,巴楚前缘断隆受西南坳陷和阿瓦提凹陷的影响 ,新生代时构造体制发生反转 ,边界向南北迁移。根据其发育过程特征 ,作者用复合前缘隆起两端迁移模式对复合前缘隆起独特的构造发育史进行了解释 :即三叠纪以来岩石圈各圈层同步挠曲变形。随着挤压应力场的增大 ,巴楚隆起在挠曲基础上不断抬升 ,形成几条大型断裂带。巴楚断隆作为一个整体沿着这几条深断裂发生剪切滑动 ,平面上表现为向冲断带迁移。在宁静期岩石圈回跳 ,整体向下滑动 ,发育负反转构造 ,平面上为向隆起轴部的迁移。前缘隆起向南北凹陷迁移时可能会在前缘隆起上出现局部伸展体制。

The Meso\|Cenozoic evolution of Bachu Fault\|Uplift is closely related to its south and north subsiding foredeep.Under the background of Indian Plate subducting under Asia\|Europe Plate,Bachu forebulge was greatly affected by the development of Southwest Depression and Awati depression.Almost all of its structure reversed,and as a result of it,both of its south and north boundary migrated.According to its evolution history and its feature,the authors tentatively use both\|side migration model to interpret the evolution of compound forebulge.Since Triassic,almost all the spheres above lithosphere synchronously became flexure.Because transpressional stress field became increasingly strong,Bachu forebulge continued uplifting and big faults formed.Then,Bachu uplift,as a whole,slipped upward along those big faults and showed migrating toward thrust zone in plane.In tectonic tranquility,the lithosphere bounded back and in consequence of it,Bachu uplift slipped down and showed migration toward craton,at that moment negative inversion structures developed.While the forebulge migrated toward its south and north foredeep,it was very possible that locally extensional stress appeared in the forebulge.