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Rate of loess accumulation in Europe in the Late Weichselian (Late Vistulian)

Fedorowicz S., Łanczont M.

Geological Quarterly

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2007

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Vol. 51, No 2

193-202

EN

The European loess profiles provides evidence of changes in climate in the last glacial cycle. The final stage of loess accumulation took place in the youngest part of the last glacial (28 to 12 ka BP). Loess accumulated in two periods: from 28 to 18 ka BP and from 18 to 13 ka BP. These two stages were separated by a short phase of weaker aeolian activity and weak pedogenesis (initial tundra gleyed soils). The loess sedimentation rate can be defined as a mass accumulation rate (MAR ex pressed in g/m2/year). This value was calculated by Frechen et al. (2003) for several dozen loess sites across western and central Europe. In this paper we calculate the MAR for several loess sites in Poland and Ukraine. The MAR distribution across Poland and Ukraine is uneven in these two intervals. The MAR values oscillate between 100 to several thou sand g/m2/year. They markedly in crease eastwards, which may be explained by the latitudinal gradient of periglacial climate in the LateWeichselian (= Late Vistulian). The MAR distribution along a N-S trend confirms its large range in western and central Europe. However, the most easterly profiles (Polish and Ukrainian ones) show less variable thick nesses as the MAR was stable at a relatively low level from several hundred to more than a thou sand g/m2/year. This stability of the MAR characterized both loess-forming intervals in this part of Europe.

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TL age of Upper Pleistocene stratified deposits measured using the additive, regeneration and R_ methods

Fedorowicz S.

Geological Quarterly

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2006

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Vol. 50, No. 2

211-218

EN

Stratified sands, which are components of the glacial and interglacial Vilkišks and Tartokai profiles (Lithuania), were used as research material for experimental dating with the TL method. Sieve analyses of samples collected from stratified sands show varying grain-sizes in the samples, with domination by different fractions indifferent samples. Four aliquot of grains of the same diameter were selected from each sample for further research by means of the additive, regeneration and R methods. The results showed some consistent patterns, which suggest a direction that future studies could take on these deposits samples. It is necessary, though, to examine grains which comprise a substantial percentage share in the total sample mass.

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Korelacja dat TL i OSL próbek z czterech profili lessowych Polski SE i SW

Fedorowicz S.

Przegląd Geologiczny

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2005

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Vol. 53, nr 11

1047-1050

EN

Nineteen samples were collected from four loess profiles: Dybawka, Tarnawce, Dankowice and Biały Kościół for purposes of TL and OSL dating. The samples were collected from loess, interstadial fossil soil, Eemian soil and Holocene soil. The results were presented in the form of TL=f (OSL) date chart. The majority of TL dates are older than OSL dates. The results of LMg luminescence dating run parallel to the straight line of equal ages. The chart shows a high similarity of TL and OSL dates. The results are consistent with the stratigraphic diagnosis. Loess grains frequently show an age heterogeneity (two or more OSL dates are provided for a single sample).