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羌塘盆地侏罗系地层基准面变化表现为从上升到下降的一个完整过程,基准面的升降变化与盆地构造演化密切相关,特别是受盆地形成演化过程中班公湖-怒江洋演化过程的控制,而且受气候变化的影响.侏罗系相当于一个长期基准面旋回层序,表现为由上升半旋回和下降半旋回组成的不完全对称旋回,其间可进一步划分为6个中期基准面旋回层序,包括2个由碳酸盐岩沉积组成的层序,3个碳酸盐岩和碎屑岩混合沉积组成的层序,一个由碎屑岩组成的层序.基准面变化过程中沉积充填特点表明,侏罗纪土阿辛期-巴柔期班怒洋已经开始扩张,巴通期-牛津期为洋盆扩张的鼎盛时期,其间由于气候干燥而影响海域面积减小,其后由于班公湖-怒江洋俯冲消减及碰撞,结束了海相沉积充填历史.
The change of basement of Jurassic strata in Qiangtang Basin is a complete process from rising to falling. The change of base level is closely related to the tectonic evolution of the basin, especially due to the evolution of the Banghu-Nujiang ocean during the formation and evolution of the basin Controlled and also affected by climate change.The Jurassic corresponds to a long-term basement cycle sequence that is characterized by an incompletely symmetric cycle consisting of ascending and descending hemislopes, which can be further subdivided into six mid-term cycles The sequence includes two sequences composed of carbonate sedimentary sequence, three carbonate and clastic mixed sediments, and a sequence of clastic rocks. Filling characteristics indicate that the Jurassic Tuasinian-Baruian period anger has begun to expand, while the Barton-Dancing period was the heyday of the oceanic basin expansion. During this period, the area affected by the dry climate decreased, - Nujiang ocean subduction and collision subduction, the end of the marine sediment filling history.