The Variation Of Quartz Optically Stimulated Luminescence Sensitivity In Xifeng Section Of Chinese Loess Plateau Since The Last Interglacial

The study on the provenance and paleoenvironment of the aeolian sedimentary sequence is helpful to understand the dust source,transport process and reconstruction of the paleoenvironment in Chinese loess Plateau.The quartz in loess is enough,which is stable and not easy to be weathered.It can retain the information of the original rock,and has potential in identifying the provenance.In this paper,we study on Xifeng optically stimulated luminescence sensitivity in Chinese loess plateau,including Heilu soil S0,Malan loess L1,the first paleosol layer S1,the second loess layer L2.By comparing the optically stimulated luminescence sensitivity in Jingyuan section and Luochuan section,the implications of provenance and transportation are as follows:(1)In the time series,by comparing the changes of the combination of fast,medium and slow components in the optically stimulated luminescence sensitivity signal of loess-paleosol samples,the following rules are found: the fast components of the optically stimulated luminescence sensitivity signal are distributed more than 90% of the paleosol samples,and the differences among the samples are small,reflecting that the optically stimulated luminescence sensitivity signal is strong and the fast,medium and slow components are uniform;In contrast,the proportion of fast components in loess varies greatly,which reflects that the optically stimulated luminescence signal is weak and the components are not uniform.(2)In the space series,both Xifeng section and Luochuan section have the rule that the optically stimulated luminescence sensitivity of the paleosol is much greater than that of the loess.The changes of the optically stimulated luminescence sensitivity of Jingyuan,Xifeng and Luochuan sections in Chinese Loess Plateau from west to east in the same period are compared horizontally.It is found that the quartz optically stimulated luminescence sensitivity of the Jingyuan section in the west of Liupan Mountain is low and the changes of glacial-interglacial periods are not obvious.The Xifeng section and Luochuan section of the east of Liupan Mountain whose optically stimulated luminescence sensitivity change significant in the glacial period and interglacial period.(3)The glacial loess may be directly derived from the western glacial moraine with a simple history and low optically stimulated luminescence sensitivity;In the interglacial period,with the weakening of glaciation,the capacity of provenance supply is greatly weakened.The large area of weathered debris from the inland of northwest China may provide provenance with high optically stimulated luminescence sensitivity for Chinese Loess Plateau.This paper preliminarily reveals that the quartz optically stimulated luminescence sensitivity in Chinese Loess Plateau may have the potential to record paleoclimate changes and reflect the differences of the process of dustl transport.