藏北高原古湖岸线分布广泛,湖泊沉积与湖成地貌发育。目前,在纳木错沿岸不仅发现了由水平层理十分发育的砂与粘土所组成的、高出湖面分别为3～12m、15～22m、25～30m与35～45m的4级湖岸阶地,以及覆于基岩之上、高出湖面60～150m的湖相沉积和多达50条左右、由扁圆的湖滨相砾石所组成的湖岸堤。而且在连结纳木错与其西北的仁错约玛、仁错贡玛、久如错的分水岭宽谷底部(分别高 The ancient lake shoreline in the northern Tibet Plateau is widely distributed, with lake sedimentation and lake-to-lake landform development. At present, not only the sand and clay, which are well developed by horizontal bedding, have been found along the coast of Nam Co, but also the 4th-order lakeshore terrace which is 3 ~ 12m, 15 ~ 22m, 25 ~ 30m and 35 ~ 45m respectively, Above the bedrock, lacustrine deposits of 60-150 m above the lake surface and up to 50 lakeshore banks of oblate lacustrine gravel are formed. But also at the bottom of the watershed valleys that link up Namtso with the northwestern ones