OSL chronostratigraphy of a loess-palaeosol sequence in Złota using quartz and polymineral fine grains

Abstract

Loess deposits are one of the most important sources of information about palaeoclimatic changes for the whole Quaternary. In general, loess is typical for cold and dry, periglacial climate and environment. The intercalated palaeosols are indicators of warmer and more humid climate representing interstadials or interglacials. In Poland, loess and loess-like formations occur in the southern part of the country, mostly in the south Polish uplands, i.e. in the Lublin, Sandomierz, and Cracow Uplands. In addition, such deposits are found in the forelands and foothills of the Carpathians and Sudetes. Luminescence dating is one of the leading techniques to establish chronologies for loess-palaeosol sequences and has been successfully applied to different minerals and grain size fractions by several research groups. OSL chronostratigraphy over the last two decades became very popular especially for loess deposits around the world, meaning that there are hundreds of new luminescence dates associated with those deposits. Our investigation is focused on the determination of chronostratigraphy for Polish loess deposits from the last glacial cycle in SE Poland up to about 130 ka. Twenty-one samples from the loess profile in Złota (21°39′E, 50°39′N) were collected for luminescence dating and six for 14C dating. Two different fractions were investigated, the polymineral fine grains (4–11 μm) and silt-sized quartz grains (45–63 μm). In addition, analyses of the magnetic susceptibility, grain-size distribution, carbonate and organic carbon content were conducted. Although further investigations are needed, our results show the suitability of the Polish loess for OSL dating and very good agreement between obtained luminescence and 14C dating results.