Paleoclimatic and Paleohydrologic Reconstruction in Western China

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The objective of this research is to establish absolute chronologies and reconstruct Quaternary climatic and water- balance variations in Qaidam Basin, an arid, high altitude basin in western China. The study material consists mainly of long drill cores retrieved by Chinese scientists at the Qinghai Salt Lakes Institute (QSLI), Academia Sinica. These cores have alternating layers of evaporitic salts and clastic sediments laid down in varied climatic conditions through the entire Quaternary or longer. On selected cores, the QSLI scientists have launched studies of stable isotopes, U-series/14C/paleomagnetic dating, pollen and grain-size analyses, Ostracods, and major/minor elemental chemistry. Detailed geochronological studies will be done using accelerator mass-spectrometric measurements of cosmogenic 26Cl and 10Be, supplemented with uranium-series dating for the more recent sections. Additionally, 36Cl and possibly 10Be buildup dating glacial moraines in the Kunlun Mountains bordering the Qaidam Basin will be carried out to provide a framework for correlating the glacial fluctuations at the headwaters of the hydrologic systems with the lacustrine variations at the terminus. The proposed research will be a joint project with the Chinese scientists at QSLI in that samples will be shared and all the relevant data will be pooled to arrive at optimal interpre- tations of the paleoclimatic and paleohydrologic history of the region. Central Asia is one of the last great "blank areas" in the world with regard to Quaternary climatic change. It is also an area of particular importance, lying, as it does, near the center of the world's largest landmass. Therefore, any light this study will shed on climatic fluctuations would contribute to global paleoclimatological science. ***