SEDIMENTARY CHARACTERISTICS AND CLIMATIC EVOLUTION OF CORE HQ IN HEQING BASIN YUNNAN PROVINCE

The environment evolution history of the Heqing Basin since 600 ka B P has been established based on the analysis of the colour,granularity,stratification and lithological assemblage of the sediments from the HQ core in combination with the study of the magnetic stratigraphy,susceptibility,content of carbonates,total organic carbon and the carbonlnitrogen ration of the sequence.There were two distinet tranformations of the enviroment connected to the tectonic movement.At a depth of 4.1m of the column,the lake basin was entrenched by rivers at about 14.2 ka B P,leading to a sudden change of the envionment.