ELEMENT GEOCHEMISTRY OF LACUSTRINE SEDIMENTS IN LOP NUR AND THEIR ENVIRONMENTAL SIGNIFICANCE OVER THE PAST 45KA BP

Major and minor geochemical elements in the sediments of core KY01 from the center of the New Lake district of the Lop Nur, were measured for paleoclimatic reconstruction. Three principal factors were identified based on principal component analysis of these elements. The first principal factor, which absolutely controls the geochemical composition of the sediments, can be used to represent the changes in humidity of the Tarim River Basin. On the basis of the dating result of AMS¹⁴C, the evolution history of regional climate during the past 45ka is evaluated. The climate of the Tarim River Basin shows a gradually drying tendency. It was humid during the mid-late last interglacial epoch and turned into drought since the late stadial of the last glaciations, with the exception of one distinct humidity event during the late last deglaciation-Early Holocene. It is also revealed that the climate change pattern of the Tarim River Basin is various rather than one simple westerly-dominated climate pattern.