塔里木西南地区二叠系分布广泛，认识其沉积和演化特征对分析二叠系油气资源潜力意义重大。结合前人研究成果，通过山前露头剖面观测、盆地钻测井解释、岩心观察、样品分析测试等，认为二叠系主要发育开阔台地、局限台地、潮坪、浅海混积陆棚、三角洲、冲积扇、滨浅湖相等多种沉积相类型。分析塔里木西南地区二叠系下、中、上统发育的主要沉积相类型，认为从早二叠世至晚二叠世，其为一个从海洋到陆地的演化过程，演化受控于海平面变化、构造活动、沉积物源供给和气候变化。不同时期，主控因素不同。下二叠统的形成受控于海平面处于相对高水位；中二叠统的形成受控于海平面下降和火山活动，海平面下降导致气候逐渐炎热干燥；上二叠统的形成受控于构造活动，构造活动导致地形变化和沉积物源的供给。%Permian in Southwest Tarim widely distributed,analyze its sedimentary characteristics and evolution as a whole regionally is significant for prediction of oil-gas resource potential.Through of foreland outcrop observation, drill-ing and well logging interpretation, core observation and sample analysis, combined with previous known results, 7 main developmental facies (open platform facies, restrcted platform facies, tidal-flat facies, shallow clasolite-carbonatite conti-nental shelf , delta facies, alluvial fan facies, shore-shallow lake facies) are recognized in Permian. The main develop-ment types of sedimentary facies of the lower, middle and upper Permian in southwestern Tarim are analyzed, from the early Permian to late Permian, it is a process of evolution from marine sediments to the continental sediments, which is controlled by the sea level change, tectonics, sediment supply and climate change, in different periods, the main control-ling factor is different. The formation and development of the Lower Permian is mainly controlled by sea level in a rela-tively high water level;The formation of Middle Permian is controlled by falling sea level and volcanic activity, sea level fall causing the climate gradually become dry and hot;the Upper Permian formation is mainly controlled by tectonic ac-tivity, which resulted the morphological changes and sediment source supply.
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