念青唐古拉山中段第四纪冰期划分

The Division of Quaternary Glacial Epochs of Middle Nyainqentanglha Range

念青唐古拉山脉呈NE和近EW走向 ,其主脊海拔 6 0 0 0～ 70 0 0余米 ,第四纪冰川活动强烈。根据第四纪地层剖面、地层层序、地质地貌特征及其相互接触关系 ,在念青唐古拉山中段可清晰地划分出 3期冰期 ,从新到老依次为 :拉曲冰期Q3 、爬然冰期Q2～ 3 、宁中冰期Q2～ 1。每次冰期及间冰期沉积物中的砾石及其岩性、砾态、沉积厚度、风化程度等都有明显区别。另外 ,还对老冰期与冰碛层。

The Nyainqentanglha Range moves in the NE (nearly EW) direction, and its main ridge is 6 000～7 000 m in elevation. Glacier activity was strong in Quaternary. According to Quaternary stratigraphic section, stratigraphic sequence, general geological configuration of the earth's surface and contact relationships, Three glacial epochs can be distinctly recognized in the middle part of the Nyainqentanglha Range, which are from old to young the Laqu glacial epoch Q 3,the Paranr glacial epoch Q 2～3 , and the Ningzhong glacial epoch Q 2～1 . The gravels in deposits of different glacial epochs and interglacial stages show obviously different rock characteristics, gravel forms, deposit thicknesses and weathering degrees. Discussions have also been made on such comparisons as the comparison of old glacial epoch with moraine layer, that of various interglacial stages and that of the glacial epochs in this area with those in other districts.