LUMINESCENCE DATING OF TERRACE DEVELOPMENT IN THE UDORKA VALLEY, POLAND

The transition from a nomadic hunter-gatherer to a sedentary lifestyle dependent on agriculture is one of human history's most important developments. One of the key regions for studying these developments is Central Europe, where the early farmers changed the biodiversity, landscape, and geomorphic processes of fully-forested environments. The present research is part of an extensive interdisciplinary project combining experts in archeology, sedimentology, and geochronology, working in the Udorka Valley in southern Poland, an archaeologically rich region occupied by human groups since the early Pleistocene. The aim of the research is to more firmly establish the age of the archeological occupations in the Udorka valley and understand the temporal relationship between successive occupations and local climatic and paleoenvironmental changes.

Our contribution was to establish the chronology of alluvial deposits sampled from the terraces left by the Udorka river near Perspektywiczna Cave. We applied Optically Stimulated Luminescence (OSL) dating methods to six samples collected from two terraces. By measuring the time elapsed since minerals were last exposed to daylight, OSL allows for the direct dating of almost all superficial deposits. Equivalent doses (De) were measured using a single-aliquot regenerative-dose (SAR) OSL protocol on the quartz grains and two SAR post-infrared infrared stimulated luminescence protocols (pIR-IR₂₂₅ and pIR-IR₂₉₀) on potassium-rich feldspar grains. The dose rates (Dr) were estimated from the radionuclide content of the sediment using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The ratio between the De and the Dr gives the burial age of the mineral grains. The combination of the dating results obtained on two minerals and with three protocols indicate that the terraces were deposited during the Marine Isotope Stages 2 to 1. At the symposium, the implications of these new dates will be discussed in relation to the Paleolithic and Neolithic occupations in the Udorka Valley.