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笔者通过西藏佩枯错盆地帮荣组剖面的野外地质调查以及沉积物粒度、磁化率、碳酸盐等环境指标的分析,结合ESR法和U系测年资料,分析了晚更新世帮荣组沉积环境演化特征。分析结果表明,127～15kaB.P.的晚更新世时,佩枯错盆地进入强烈断陷阶段,佩枯错古湖经历了初始浅湖期,发展深湖期和萎缩浅湖期一个完整的湖泊演化过程。127～56kaB.P.,气候温暖湿润,湖水增加,古湖发育进入浅湖期;56～31kaB.P.,湖水波动上升,古湖进入发展深湖期;31～15kaB.P.,湖泊步入萎缩浅湖期,15kaB.P.左右出现的冻融褶皱,可能指示该区进入冰缘期。
Based on the field geological survey of the Bangrong Formation in the Permian Basin, Tibet, and the analysis of sediment grain size, magnetic susceptibility and carbonates, the authors combined the ESR method and U-series dating data to analyze the characteristics of the Late Pleistocene Bangrong Formation Sedimentary environment evolution characteristics. The results show that during the late Pleistocene of 127 ~ 15kaB.P., the Permian Basin entered a strong faulted depression, and the ancient lake of Perkara experienced the initial shallow lake, the deep lake and the atrophy shallow lake Lake evolution. 127 ~ 56kaB.P., the climate is warm and humid, the lake increased, the ancient lake developed into the shallow lake period; 56 ~ 31kaB.P., The lake fluctuated and the ancient lake entered the deep lake period; 31 ~ 15kaB.P., The lake step Into the atrophy shallow lake, 15kaB.P. around the freeze-thaw fold, may indicate that the area into the ice edge.