ARCHAEOLOGY, LATE-QUATERNARY LANDSCAPE EVOLUTION, AND ENVIRONMENTAL CHANGE IN THE UPPER DRIFTWOOD CREEK BASIN, BARBER COUNTY, KANSAS

Abstract

This study focused on valley fills in the upper Driftwood Creek basin, a 3rd order drainage network in south-central Kansas to determine the geologic potential for stratified cultural material and to reconstruct a record of Late-Quaternary environmental change. A suite of radiocarbon ages provide a numerical chronology for landscape evolution, and δ13C values of soil carbon provide a record of paleo-environmental change. The results generally conform to existing conceptual models for landscape evolution and paleo-environmental change on the Central Plains. Late-Wisconsinan alluvium, rarely found in the valleys of small streams east of the High Plains, is found beneath T-2 terrace remnants and alluvial fans in the upper Driftwood Creek valley. Early and mid-Holocene deposits are present beneath alluvial fans high in the drainage network, and late-Holocene alluvium is stored beneath T-1 terraces. Buried soils recorded within these alluvial fills are high probability targets for locating stratified cultural material. δ13C values of soil carbon indicate that the transition from a C3 to a C4 dominated plant community began after ca. 14,000 14C yr B.P. in the study area. The isotopically heaviest δ13C values occur after ca. 6,700 14C yr B.P. in the study area, indicating a generally warm, dry middle Holocene.