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OSL chronostratigraphy for loess deposits from Tyszowce – Poland

100%

Moska P. , Adamiec G. , Jary Z. , Bluszcz A.

tom Vol. 44, no. 1

307--318

The presented work concerns a loess profile located in Tyszowce, in the eastern part of Poland on the Volyn Upland, close to the Ukrainian border. The investigated loess formation is well preserved and is characterised by clear stratigraphic units providing an opportunity to refine the loess chronostratigraphy in Poland. In the paper, we present luminescence ages of loess from the last glacial cycle in SE Poland (up to about 100 ka) together with seven radiocarbon ages. Twenty-one samples were collected and dated using infrared (post-IR IRSL) and blue light stimulated luminescence dating. Two fractions were used, namely polymineral fine grains (4–11 μm) and medium sized quartz grains (45–63 μm). The obtained luminescence ages show very good agreement of both methods in relation to loess deposits, however for the fossil soil units the post-IR IRSL method yields older ages. Radiocarbon dates also confirm luminescence chronostratigraphy for younger units. Moreover, the luminescence results are supported by detailed analyses of grain size distribution, carbonate content and magnetic susceptibility variations allowing to create a comprehensive picture of chronological evolution of this site.

The Influence of cesium activity on the annual dose for OSL dating

100%

Moska P. , Poręba G. J. , Bluszcz A.

2004

tom Vol. 23

15-19

Introduction of single aliquot protocols dramatically improved the accuracy of absorbed dose measurements, so now dating of very recent events, which ages are of the order of tens of years or even single years, becomes possible. The overall accuracy of the OSL age is now limited by the correct assignment of the dose rate. Certain types of recent sediments may contain fall-out radioisotopes that increase the average annual dose. In this paper we demonstrate that the contribution from fall-out radioactivity may be significant and the way to take it into account by using a modified age equation.

Luminescence chronostratigraphy for the loess deposits in Złota, Poland

63%

Moska P. , Adamiec G. , Jary Z. , Bluszcz A. , Poręba G. , Piotrowska N. , Krawczyk M. , Skurzyński J.

2018

tom Vol. 45, no. 1

44--55

Loess formations in Poland display a close relationship with cooling and warming trends of the Northern Hemisphere during the Pleistocene. Loess sequences sensitively record regional palaeoclimatic and palaeoecological changes. The Złota loess profile (21°39’E, 50°39’N) provides a unique opportunity to reconstruct climate conditions in the past in this part of Poland. This continuous sequence of loess and palaeosol deposits allows to distinguish between warmer and more humid climate which is favourable for soil development and much colder and dry periods which are conducive to loess accumulation. The silty and sandy aeolian material originates mainly from weathered rock surfaces affected by frost shattering or from glaciofluvial/fluvial deposits of river flood plains. 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. We used different techniques to establish a chronological framework for this site. 21 samples for luminescence dating were collected from the investigated loess profile in Złota. Infrared post-IR IRSL dating method was applied to the polymineral fine grains (4–11µm). The dating results are accompanied by detailed analyses of the geochemical composition, organic carbon and carbonate. Also, analysis of magnetic susceptibility and grain-size distribution were investigated. Based on such a large stratigraphic dataset an age-depth model using OxCal has also been constructed for this site.