塔里木盆地塔中低凸起古构造演化与变形特征

通过区域地质和构造地震精细研究，提出了塔里木南缘早古生代板块构造控制塔南—塔中从伸展到挤压盆地演化：寒武纪—早奥陶世板缘拉张控制了塔中北斜坡断陷构造；中奥陶世北昆仑洋盆关闭后塔中前缘隆起；晚奥陶世—晚泥盆世塔中前陆冲断与走滑构造变形。晚奥陶世塔南前陆冲断构造由东南向西北方向传播，形成塘北—塔中南—塔中5号断裂带等弧形断裂体系和塔中低凸起中西段与Ⅰ号断裂带小角度斜交的走滑断裂体系。冲断构造位移的传播受控于两个滑脱层：其一是沿寒武系内部膏盐岩的滑脱，形成弧形冲断构造，终止于塔中南缘断裂带；另一个是沿中地壳韧性变形带的滑脱，形成塔中1号断裂带东端的弧形构造带。塔中1号断裂带东段的构造变形方式主要为向北传播水平位移的断层传播褶皱和向南反向冲断的楔形构造。塔中低凸起的中西段右行走滑构造导致了向东收敛的扫帚状走滑断裂体系的形成，剖面发育花状构造。塔中低凸起的古构造演化与变形特征、构造变形样式、构造变形成因和断裂体系，是克拉通盆地内部叠合盆地深层的主要构造地质特征。

Paleo tectonic Evolution and Deformation Features of the Lower Uplift in the Central Tarim Basin

After analyzing the regional geology and the seismic interpretation, the writers make conclusions that structural geologic evolution from extension to compression in the Southern-Central Tarim basin during early Paleozoic was controlled by the plate tectonic of southern margin of the Tarim plate. Extension and rift structure occurred in the northern margin of Central Tarim Basin under the control of extension in passive continent margin during Cambrian to Early Ordovician; It was a forebulge in the Central Tarim Basin after closure of the north Kunlun ocean in Middle Ordovician; the thrust nappe and strike deformation from Late Ordovician to Devonian is the main structural features which were kept up to now. The foreland thrust deformation, which propagated from southeast to northwest in Late Ordovician, result in the formation of the arc shaped fault systems of Tangbei fault-south margin fault-No. 5 fault of central Tarim basin and formation of the strik-slip fault system in central-western section of the lower uplift of the central Tarim Basin, which is oblique intersecting with the fault No. 1. The propagation of thrust displace is along two detachment layer. One is the evaporite rocks bed in the Cambrian, the other one is the ductile layer in the middle crust. The main structural style is fault propagation fold and wedge structure in the east segment of fault No. 1. The main style is flower structure of strike faults system which like a broom on the plane distribution in the west segment of fault No. 1. The ancient structural evolution and deformation features, structural style, structure formation cause and the fault system in the Central Tarim Basin are main structural geological features in the depth of superimposition Cratonic basin.