Abstract

Early Medieval archaeological site was studied on the Upper Dnieper River floodplain. Human occupation of the floodplain was possible it had not been subject to inundation in the VIII-X centuries AD. Later flooding had restored and Early Medieval palaeosurface was buried by overbank deposits. A 20×20 m coring grid was produced to study depth of Early Medieval paleosurface marked by buried soils, cultural layer and peat horizon. As a result, floodplain palaeotopography for the X century AD and thickness of last 1000-yr deposits has been obtained. Sedimentation rate averaged over the key site is estimated at 130 cm/1000 yrs, or 1.3 mm yr^-1, with local variations in the range 20-290 mm yr^-1. Correlation analysis was used to reveal that this variability is controlled by distance from palaeo- and modern river channel (major factor) and by local elevation above the river (secondary factor). In depression of a small floodplain lake sedimentation rates show negative relationship with elevation. Here coastal vegetation is supposed to play important role in sediment trapping.

Keywords: Floodplain, sedimentation rates, overbank deposits, buried soil, cultural layer, archaeology, alluvial chronology, Late Holocene