VARIATIONS IN LOESS AND PALEOSOL PROPERTIES AS INDICATORS OF PALEOCLIMATIC GRADIENTS ACROSS THE LOESS PLATEAU OF NORTH CHINA

New data are presented on micromorphology, magnetic susceptibility and particle size characteristics of three soil/sediment units at four lo cations along a WNW-ESE transect across the Loess Plateau of North Chi na. Differences and spatial trends are used to assess the sensitivity of such data as proxies of regional palaeoclimatic gradients. The stee pest climatic gradient suggested by the magnetic susceptibility for th e S1 palaeosol is at the eastern (humid) end of the traverse. Micromor phology and particle size analysis show that the loess units in the ea st are richer in clay than the best developed palaeosols in the semi-a rid west, and that particle size in the west appears to provide a more sensitive record of climatically-driven changes than magnetic suscept ibility. The use of surface and near-surface soils as a datum for infe rring palaeoprecipitation values is reviewed in the light of recent ev idence of substantial degradation of such soils. Micromorphological an d particle size analysis of closely spaced samples from loess-palaeoso l sequences is a sensitive addition to magnetic susceptibility stratig raphy and correlation.