关键词: 查格勒布鲁剖面, 晚更新世, 东亚季风, 古风成砂, 沉积

Abstract: The evidences of climatic stratigraphy, which include sedimentary facies, grain size,composition, and Paleoperiglacial phenomena, indicate that the climatic evolutions in the south of Badain Jaram Desert can be divided into 3 stages since late Pleistocene, which are two warmer and moister ones in the early stage of late Pleistocene(Q₃¹) and in Holocene(Q₄), and a dry and cold stage in the late stage of late Pleistocene(Q₃²). The main elements which influence the climatic changes in this area are the fluctuation of the quaternary glacial climate and the uplift of Qinghai-Xizang Plateau.One of the evident phenomena of the climatic changes in this area is the advances and retreats of the summer monsoon fringe. During the 18ie interglacial period(Q₃¹), the fringe extended its range to Guaizihu, which lies to the north 180 km away from Chagelebulu, the landscape was the temperate thorny tree grasslands. During the last glacial period, the winter monsoon dominated the climate in this area, the summer monsoon fringe, however, retreated to the middle-lower reaches of Changjiang drainge basin, the landscape turned to temperate desert. During Holocene, the fringe come back to west and north, and formed sandy paleosol in sandy loess of Chagelebulu section in Holocene.

Key words: Chagelebulu section, Late Pleistocene, Monsoons, East Asia, Eolian paleosands Desposition