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贺兰-川滇南北向构造带是划分中国大陆东西的地幔陡变带,其南段川滇南北向构造带是由几个性质不同的构造系统叠加组成的复杂构造带.研究发现,位于扬子地块西缘的川滇南北向构造带发育由雁行状左行走滑断裂为骨架的走滑构造带.走滑构造带经历了两期构造叠加,早期变形为北东-南西挤压应力场形成的一系列北西-南东走向的逆冲断裂,晚期北西-南东挤压应力场环境下沿先前的逆冲断层形成一系列左行走滑断裂.在这些左行走滑断裂之间,发育一些中生代盆地,盆地沉积相和古流向研究显示,这些盆地的形成受走滑断裂控制.因此,依据盆地内最老地层限定,扬子西缘走滑构造带形成于早中生代.作者认为,这个走滑构造带的形成,很可能与晚三叠世-侏罗纪时期扬子地块顺时针旋转并持续向北俯冲-碰撞有关,川滇南北向构造带在早中生代中国大陆的主体碰撞拼贴过程中就已经开始形成.
Helan - the north-south Sichuan-Yunnan tectonic belt is a mantle steep change zone that divides the east-west continent of China into a complex structural zone composed of several structural systems superimposed by the south-north Sichuan-Yunnan-north tectonic belt.The study found that in the Yangtze Delta The NW-trending tectonic belts in the western margin of the block developed strike-slip tectonic belts from the goose-slip strike-slip faults to the skeleton.The strike-slip tectonic belts experienced two phases of structural superimposition, and the early deformation was the formation of the North-East-South Western extrusion stress field A series of north-south strike thrusts formed a series of left-lateral strike-slip faults along previous thrusts in the late Northwest-South East extrusion stress field.A number of Mesozoic basins developed between these left-lateral strike-slip faults The study of sedimentary facies and paleocurrent in the basin shows that the formation of these basins is controlled by strike-slip faults, so the strike-slip tectonic belt of the western margin of the Yangtze was formed in the early Mesozoic according to the definition of the oldest strata in the basin. Is probably related to the clockwise rotation of the Late Triassic-Jurassic Yangtze block and its continued northward subduction-collision. The main strike collision of the Sichuan-Yunnan North-South tectonic belt in the early Mesozoic in mainland China The process has already begun to form.