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Shorelines are widespread and lake deposits and lake geomorphology are well developed on the northern Tibetan Plateau. Through field observations of lacustrine deposits of Nam Co-the highest and largest Quaternary lake in Tibet, the authors found four-step shore terraces composed of sands and clays with well-developed horizontal bedding and 3-12 m, 15-22 m, 25-30 m and 35-45 m higher than the lake surface respectively, lacustrine deposits resting on the bedrocks and 60-150 m higher than the lake surface, and up to -50 levees composed of oblate lakeshore gravels. Moreover they found lacustrine and lakeshore deposits making up the terraces and levees on the bottoms of wide dividing valleys connecting Nam Co with the Rencoyuema, Rencogongma and Jiuru Co northwest of Nam Co (the valley bottoms are 20 m, 90 m and 60 m higher than the above-mentioned three lakes) and on slopes north of it, i.e. terraces II and III of Nam Co. Thus they confirm that Nam Co and Ring Co-Jiuru Co had connected with each other seve
Shorelines are widespread and lake deposits and lake geomorphology are well developed on the northern Tibetan Plateau. Through field observations of lacustrine deposits of Nam Co-the highest and largest Quaternary lake in Tibet, the authors found four-step shore terraces composed of sands and clays with well-developed horizontal bedding and 3-12 m, 15-22 m, 25-30 m and 35-45 m higher than the lake surface respectively, lacustrine deposits resting on the bed rocks and 60-150 m higher than the lake surface, and up to -50 levees composed of oblate lakeshore gravels. either as lacustrine and lakeshore deposits making up the terraces and levees on the bottoms of wide dividing valleys connecting Nam Co with the Rencoyuema, Rencogongma and Jiuru Co northwest of Nam Co (the valley bottoms are 20 m, 90 m and 60 m higher than the above-mentioned three lakes) and on slopes north of it, ie terraces II and III of Nam Co. so they confirm that Nam Co and Ring Co-Jiuru Co had connected wi th each other seve