通过野外地质观测结合地震反射剖面综合构造解释,在青藏高原中部色林错—伦坡拉古近纪沉积凹陷及邻区厘定3条较大规模的逆冲推覆构造,由逆冲断层、逆冲岩席、飞来峰、构造窗及伴生褶皱组成.沿班公—怒江缝合带发育赛布错—扎加藏布逆冲推覆构造,伦坡拉盆地北部发育双重推覆构造,拉萨地块北缘发育色林错—吴如错逆冲推覆构造,估算推覆距离分别为38~50 km.羌塘地块南缘自北向南逆冲推覆,拉萨地块北缘自南向北逆冲推覆,两者对冲导致色林错古近纪盆地及沉积地层发生比较强烈的褶皱变形,形成宽约20 km大型向斜构造.色林错—伦坡拉逆冲推覆构造运动开始时间为晚白垩世晚期,古近纪不同时期均发育逆冲断层,前锋逆冲断层和底部拆离滑脱构造主要形成时期为古近纪晚期—中新世早期.古近纪逆冲推覆构造对伦坡拉和色林错河湖相沉积盆地、烃源岩形成演化、油气成藏及保存条件具有显著控制作用.%Field geological survey and seismic reflection profiling have revealed three regional thrust systems in the Siling Co–Lunpola Paleogene depression and its adjacent areas. Each thrust system consists of reverse faults, thrust sheets, nappes, structural windows and folds. The Serbug Co–Zajiazangbu thrust, the Northern Lunpola duplex thrust and the Siling Co–Wuru Co thrust were formed along the Bangoin–Nujiang Suture, the northern Lunpola Basin and the northern margin of the Lhasa Block, respectively. The minimal displacement of each thrust system is estimated to be 38~50 km. Southward thrust occurred on the southern margin of the Qiangtang Block, and northward thrust occurred on the northern margin of the Lhasa Block. Such tectonic movement resulted in intense folding of the Lunpola Basin and the Paleogene lacustrine strata, forming the Lunpola syncline as wide as 20 km. The Siling Co–Lunpola thrust was initiated in Late Cretaceous and intensified in the Paleogene, and the frontier thrust and lower detachment faults were formed in the late Paleogene–Early Miocene. The Paleogene thrust along the Bangoin–Nujiang Suture controlled the sedimentary depression, the hydrocarbon source rock evolution, and the formation and preservation of oil reservoirs in the Lunpola and Siling Co Basins.
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