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根据西藏纳木错及邻区发现的多处湖岸阶地和高位湖相沉积,确定了藏北高原古大湖的存在。水准测量表明,在纳木错沿岸发育了6级湖岸阶地,以及拔湖48～139.2m的高位湖相沉积;在拔湖26m以下,发育有8～30条湖岸堤;一条明显的湖蚀凹槽则集中出现在拔湖17.5～19.8m的高度上,与纳木错和仁错的分水垭口的高度相当。纳木错沿岸和邻区湖相或湖滨相沉积物的铀系年龄测定表明,高位湖相沉积形成于115.9～71.8kaB.P.的晚更新世早期;第6至第2级阶地形成于53.7～28.2kaB.P.的晚更新世中晚期;与湖蚀凹槽相当的湖滨相沉积则稍早于29.3kaB.P.;第2至第1级阶地,14C测定结果为2350～10390aB.P.。
According to the deposits of many lakeshore and high lacustrine deposits found in the Nam Co Mountains and adjacent areas of Tibet, the existence of the ancient lakes in the northern Tibet Plateau has been confirmed. The leveling measurements show that there are 6 lakeshore terraces and 48 ~ 139.2m lacustrine lacustrine deposits in the coast of Nam Co; 8 ~ 30 lakeside embankments developed below 26m; a clear lacustrine groove Concentrated in pulling Lake 17.5 ~ 19.8m height, and the wrong Namco fault and water diversion Pass height. The uranium ages of the lacustrine or lacustrine facies deposits along the Nam Co coast and adjacent areas show that the upper lacustrine facies formed in the late Late Pleistocene from 115.9 to 71.8 ka BP; the sixth to second terraces formed from 53.7 to 28.2 The late Pleistocene epoch of kaB.P., the lacustrine facies equivalent to the lake-eroded groove was slightly earlier than 29.3 kaB.P .; the terraces of the 2nd to the 1st terraces, and the 14C measured from 2350 to 10390 aB.P.