A Multi-cycle Climatic Fluctuation R

A Multi-cycle Climatic Fluctuation R

2010-08-04

The Last Interglacial Period strata in the Milanggouwan section in the Salawusu River valley on the Ordos Plateau, China, have 8.5 sedimentary cycles composed alternately of eolian dune sands, fluvio-lacustrine facies and paleosols. Based on comprehensive analyses on the distribution of magnetic susceptibility and CaCO3 and paleo-ecology indicated by fossils in the region, it is considered that the sedimentation cycles

resulted from dry-cold and warm-humid climate fluctuations. Magnetic susceptibility values and CaCO3 contents in stratigraphic sectors a¡­ , a¡­¡é,a¡­¡è and a¡­?,

a¡­¡êbasically respectively present peaks and low vales, and the former three can in time correlate with MIS5a, MIS5c and MIS5e successively and the latter two with MIS5b and MIS5d. In addition, some horizons of eolian dune sands and the low vales of their magnetic susceptibility and CaCO3 are also correlated with 6 periods of cooling events indicated by the higher content of foraminifer Neogloboquadrina pachyderma (S.) documented in the V29-191 drill in the North Atlantic and the cold events recorded by ?¡ä18O in the ice cores in GRIP, especially with 9 periods of dust events in Chinese Loess Plateau.

??? ¨¨€¡­???Li Baosheng David Dian ZHANG WEN Xiaohao DONG Yuxiang ZHU Yizhi JIN Heling ???¨¨€¡­???????????Li Baosheng(Department of

Geography,South China Normal University,Guangzhou,Guangdong 510631;State Key Laboratory of Loess and Quaternary Geology,Institute of Earth Environment,Chinese Academy of Sciences,Xi'an,Shaanxi 710061)

David Dian ZHANG(Department of Geography and Geology,The University of Hong Kong,Hong Kong)

WEN Xiaohao(Department of Geography,South China Normal University,Guangzhou,Guangdong 510631)

DONG Yuxiang(Department of Geography,Sun Yat-Sen University,Guangzhou,Guangdong 510275)

ZHU Yizhi(State Key Laboratory of Loess and Quaternary Geology,Institute of Earth Environment,Chinese Academy of Sciences,Xi'an,Shaanxi 710061) JIN Heling(Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou,Gansu 730000)

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SINICA ?1¡ä??????¡¤(???)???2005 79(3) ????¡À????¡¤???P5 ?¡­3¨¦¡±?¨¨¡¥?????last interglacial period dune events cold-warm climate cycles Salawusu River valley Inner Mongolia