INVESTIGATION OF THE EVOLUTION AND ENVIRONMENT CHANGE OF TYPICAL LAKES IN YUNNAN

This paper introduces the primary results of investigations of seven lake systems and geomorphology of the lake areas in Yunnan.A total of 140 m of drilling cores were recovered from the wells in the seven lakes and bed mud samples were taken from some of the lakes.Investigation and study of the lake terraces, layered geomorphology and related strata indicate that there exist two to three distinct highstand banks and that many conch layers are distributed in the lakes, which are higher than dolinen and formed during the later Pleistocene.The sedimentary characteristics of the section at the top of Snake Mountain and previous dating data suggest that the deposition of the Sheshan Formation ended in the late part of the last glacial epoch.