THE LATE CENOZOIC EOLIAN DEPOSITS IN THE LOESS PLATEAU AND THE ARIDITY OF EOLIAN DUST SOURCE REGION

Global aridity is a serious environmental problem and thus gradually noticed by governments and scientists. The Late Cenozoic eolian sediment rate has been calculated on the basis of some lithostratigraphy and manetostratigaphy of Lingtai and Zhaojiachuan sections. Both the sediment rate of eolian deposits in the Loess Plateau and eolian flux of ODP884/885 have increased stepwisely since 4 5Ma B P , which reflect the gradual aridity of eolian dust sources region. Especially the sharply increasing of two records between 3 6 and 2 6Ma B P indicates the aridity development of eolian dust sources region in interior Asia, which may be due to the tectonic uplifting of Tibet Plateau during this period.