Wyniki wyszukiwania - BazTech

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Geologia, stratygrafia i interpretacja genetyczna glin lodowcowych wzniesienia czołowo morenowego w Wolsku Dolnym

Ratajczak-Szczerba M.

Landform Analysis

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2011

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Vol. 16

111-114

EN

The outcropin Wolsko Dolne is located in one of the hills ofWyrzysk Oscillacion end moraines. There were recognized four complexes of glacial and glaciofluvial deposits. Glacial tills were identified with help of detailed lithofacial analisys. There were recognized textural, structural features and petrographic composition of glacial tills

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Chronology of the last deglaciation in the south-eastern Baltic Region on the basis of recent OSL dates

Raukas A., Stankowski W. T. J., Zelčs V., Šinkunas P.

Geochronometria

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2010

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Vol. 36

47-54

EN

The study of the deglaciation chronology in the south-eastern Baltic Region belonging to the outer zone of the last Pleistocene glaciation has a long history. The Finnish investigator H. Hausen (1913) who worked in the north-western portion of the East-European Plain at the beginning of the 20th century was the first to attempt a reconstruction of the course of glacial retreat during the last glaciation. At that time investigators had no physical dating methods and the time scale based on varvometric method, introduced by the Swedish geologist G. de Geer (1912) who divided the deglaciation history of Scandinavia into Daniglacial, Gotiglacial and Finiglacial, each of which had different palaeoglaciological conditions. During last decades different dating methods, including 14C, ESR, luminescence methods and 10Be techniques have been used, but they could not help essentially improve the existing stratigraphical charts and many problems of topical interest in the history of deglaciation have not been solved yet. During last years the first two authors have studied the suitability of OSL method for the geochronological purposes, paying the most attention to the waterlaid sediments. In the first step they have found the most promising genetical varieties of glaciofluvial sediments (glaciofluvial deltas and sandurs) and in this paper they widened the study area to all three Baltic states with close cooperation with Latvian and Lithuanian colleagues. The obtained results demonstrated, that not all mineral grains in the uppermost glaciofluvial and glaciolacustrine sediments were fully bleached during the last deglaciation. Probably the older sediments also influenced to the luminescence results. It means, that stratigraphic conclusions based on single dates or their small sets are inadmissible and in each case luminiscence dating requires a verification using other methods.

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Influence of sedimentological composition on OSL dating of glaciofluvial deposits : examples from Estonia

Raukas A., Stankowski W.

Geological Quarterly

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2005

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Vol. 49, No. 4

463--470

EN

We assess the suitability of luminescence (TL and OSL) dating techniques for establishing a precise Late Pleistocene chronology for the northern Baltic area, and show on the basis of the fine sand/coarse silt fraction of subaqueous deposits, how sedimentological composition influences the dates obtained. Turbidity, loading by fine suspended material, water depth, velocity of outwash streams and transport length, and also perhaps rapid night-time sedimentation and incorporation of older, unbleached particles are factors that variably influence the extent of bleaching of the luminescence signal, and thus, cause variability of dates obtained. Alongside reliable dates for "late-glacial" deposits between 11 000-15 000 OSL years BP, many entirely unreliable dates from 8 000 ±300 to 114 000 ±8 000 OSL years BP have been obtained. This means that the age determination of glaciofluvial deposits is extremely difficult in practice. This applies particularly to intermorainic sediments, the exact genesis of which is unknown. The paper is addressed to the investigators wishing to use luminescence dating techniques to establishing the Pleistocene chronostratigraphy of glaciofluvial deposits.

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Relics of the oldest glaciofluvial sediments of the Czarny Dunajec River in Podhale (Western Carpathians)

Kukulak Józef, Augustowski Karol

Studia Geomorphologica Carpatho-Balcanica

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2022/2023

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Vol. 56/57

79--98

EN

Described are relics of glaciofluvial deposits related to the Mindel glaciation in the Tatra Mountains, preserved along the course of the Czarny Dunajec River in Podhale (Western Carpathians). Distribution, spatial relations, hypsometry and petrography are described for eleven selected sites in Pogórze Gubałowskie and Kotlina Orawska. The mechanisms and the degree of their removal are discussed in the context of their position relative to the pattern of drainage. Their predominantly quartzitic composition is attributed to selective weathering. Local disturbances of their hypsometric position are related to neotectonic movements.