PROVENANCE, TRANSPORT AND CHARACTERISTICS OF MODERN AEOLIAN DUST IN WESTERN GANSU PROVINCE, CHINA, AND INTERPRETATION OF THE QUATERNARY LOESS RECORD

Results of a comparative analysis of a 4-year set of monthly samples o f airfall dust with samples from surface alluvial fan deposits, desert sand dunes and late Pleistocene loess and palaeosols in Gansu Provinc e, northern China, are summarized. They suggest a qualification of the conventional view that the sand deserts were the primary single sourc e of the Quaternary loess. It is argued that silts deflated from the s urfaces of the large and numerous piedmont alluvial fans in the Hexi C orridor, Gansu, constituted a major contribution to the loess column i n the western region of the Chinese Loess Plateau. The present dust fa ll regime in the Hexi Corridor suggests that distribution and rate of accumulation of airfall silt in the present interglacial is similar to that in parts of the Pleistocene loess record. (C)1998 Academic Press Limited.