ZHAO Qing, ZHENG Xiangmin, ZHOU Limin, WANG Hui, CHEN Yuanyuan, 

LV Honghua, REN Shaofang

(Key Laboratory of Geographic Information Science of Ministry of Education, School of Geographic Science, East China Normal University, Shanghai 200241, China)

Abstract：Based on the optically stimulated luminescence (OSL) dating of the shengshan Loess deposit on Zhoushan Island in the eastern monsoon region of Zhejiang Province, the elemental geochemical characteristics of the loess deposit were probed and the paleoclimate significance was revealed.. Results of OSL dating showed that the Shengshan Island loess was deposited during the last glacial period. The geochemical components in loess are mainly SiO2, Al2O3 and Fe2O3，accounting for 90.22%. Compared with Luochuan loess, Luochuan paleosoil and Zhenjiang Xiashu loess, the major elements of Al and Fe in the loess of Shengshan Island were relatively enriched, and the elements of Ca, Na and K were relatively depleted. Chemical index of alteration (CIA) was 85.1.. From the eastern Shengshan Island to the northwestern Luochuan loess Plateau, the weathering intensity of the loess varies significantly. The overall pattern was ranked in the following order: Shengshan Island loess > Zhengjiang xiashu loess > Terrigenous shale > Luochuan paleosoil > Luochuan less > Upper continental crust (UCC). The average magnetic susceptibility of the shengshan Island loess deposition profile was 70.9×10-8 m3/kg, and the magnetic susceptibility fluctuated obviously with depth.Combined with the magnetic susceptibility indices, the geochemical records of the shengshan Island loess revealed that the climate fluctuated from warm and humid to cold and dry, and then to warm and wet during the last glacial stage, which was consistent with the climate change in MIS3 reflected by the Huining and Xiashu loess.The climatic characteristics of the glacial stage during the last glacial period in the loess sedimentary records of Shengshan Island were also consistent with global climate change.

Key words：island loess deposit; geochemical elements; chemical weathering; climate change

EARTH AND ENVIRONMENT Vol.51, No.1, Tot No.351, 2023, Page 17