Some aspects of age assessment of Holocene loess colluvium: OSL and ¹³⁷Cs dating of sediment from Biała agricultural area, South Poland

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• 作者：Grzegorz Porę ; ba^a ; ^{grzegorz.poreba@polsl.pl"" rel=""nofollow} ; Zbigniew &#x15a ; nieszko^b ; Piotr Moska^a
• 刊名：Quaternary International
• 出版年：2011
• 出版时间：1 August 2011
• 年：2011
• 卷：240
• 期：1-2
• 页码：44-51
• 全文大小：696 K

文摘

At the end of the Pleistocene in Central-Eastern Europe, the accumulation of periglacial loess had already finished. From the end of loess accumulation to the establishment of grass cover and forest succession in this area, a phase of active modeling of the land surface by slope processes occurred. Before the beginning of the Holocene, this activity stopped and mollisol and alfisol formation started. These soils are preserved beneath Holocene colluvia. Until the Neolithic age, the area of loess formations in Poland was uninhabited. The extensive Neolithic agriculture locally induced soil erosion, causing slopewash on farmedslopes. The scale of this process and establishing the age of the successive stages of the prehistoric soil erosion in loess deposits in Poland is a key problem in the investigations of the human–environment relationship in prehistory. Chronostratigraphy of the preserved Holocene colluvia is very helpful in the solution of these problems. Optical (OSL) dating was applied in chronostratigraphical analyses. Due to expected partial bleaching during sediment transport, a single-aliquot regenerative dose protocol (SAR) was applied. Insufficient bleaching during transport on the slope is expected to be a serious problem for luminescence dating of loess colluvia, and causes overestimation of the OSL age. Quartz from the study site was suitable for age determination by SAR. The youngest 50-year old colluvia were also studied using the ¹³⁷Cs method. The reliability of the obtained results is discussed in this paper, as well as the influence of environmental processes and type of the applied methods on chronological assignments. The precise age determination of loess colluvia is important for study of the human impact on the environment. The results of OSL dating show that soil erosion started in the Neolithic, with three phases of soil erosion: Neolithic, Middle Ages, and modern.