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Znaczenie warunków geomorfologicznych dla powstania i współczesnego stanu wybranych torfowisk w środkowym odcinku doliny Widawki

Stępień E., Forysiak J.

Landform Analysis

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2017

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Vol. 34

51--61

PL

Wśród form geomorfologicznych Kotliny Szczercowskiej znaczną powierzchnię stanowią równiny torfowe. W artykule przedstawione są trzy przykłady torfowisk, dwa z nich powstały w paleomeandrach Widawki, położonych w obrębie dna dolinnego, trzecie leży w obniżeniu na terasie nadzalewowej, otoczonym piaskami eolicznymi. Rozpoznana została miąższość utworów biogenicznych, a w wybranych profilach wykonano oznaczenia parametrów fizykochemicznych i wydatowano spągowe warstwy torfów. Akumulacja torfów rozpoczęła się w późnym vistulianie i trwała w holocenie. W torfowiskach położonych w dnie doliny odłożyły się głównie torfy niskie, zaś w torfowisku położonym w otoczeniu form eolicznych torfy przejściowe i wysoki. Położenie geomorfologiczne znajduje również odbicie we współczesnym stanie torfowisk, które leżą w brzeżnej części leja depresji powstałego w otoczeniu odkrywki węgla brunatnego.

EN

In Szczerców Basin peatlands have a significant participation among geomorphological forms. The article presents three examples of peatlands, two of them are formed in palaeochannel of Wiawka river, in valley floor, third one is located in small depression in high terrace, surrounded by aeolian sands. Thickness of biogenic deposits were examined and in selected cores were measured basic physico-chemical parameters. The bottom of peat layers was dated of radiocarbon method. Accumulation of peat series was started in Late Vistulian and gone in Holocene. In peatlands located in valley floor peat was deposited in fens, in high terrace it was transitional and raised peatland. Geomorphological features are important for the modern situation of peatlands, because they lie in the marginal part of the depression of ground water table, caused by the opencast mine of brown coal.

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Reconstruction of local environments of ancient population in a changeable river valley landscape (the middle Vychegda River, Northern Russia)

Karmanov V. N., Zaretskaya N. E., Panin A. V., Chernov A. V.

Geochronometria

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2011

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Vol. 38, no. 2

128-137

EN

In river valleys, both human occupation and subsequent preservation of archaeological sites are affected by active landscape transformation caused by river lateral migration, inci-sion/aggradation cycles and changes of river hydrological regime. In the middle Vychegda River val-ley (Northern Russia), there are numerous traces of human presence since the Mesolithic. We exploit multi-disciplinary archaeological, geomorphological and geochronological approach to elucidate the environmental preferences of settlements positioning during different epochs of the Holocene. High resolution space image supplemented with data on alluvial stratigraphy derived from bank exposures and hand cores, as well as 51 radiocarbon dates were used to make the geomorphic map showing ages of floodplain/terrace segments and palaeochannels. Using this map together with sediment facial in-terpretation, position of archaeological sites was analysed in the context of local geomorphic and hy-drologic situation. The majority of archaeological sites and modern settlements are found on terraces at river banks or at oxbow lakes which were well connected to the river. Few exceptions from this rule may be explained by seasonal character of dwelling functioning, ritual burial practice or speciali-zation of settlements. Geomorphic situation was used as a background for planning further prospec-tion of different-age archaeological objects.

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Fluvial sedimentation of sandy deposits of the Słupiec Formation (Middle Rotliegendes) near Nowa Ruda (Intra-Sudetic Basin, SW Poland)

Kurowski L.

Geologia Sudetica

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2004

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Vol. 36

21-38

EN

The sandy sediments described in this paper are the lower, approximately 400-meter-thick part of the Słupiec Formation, which is part of lower Permian clastic deposits in the Intra-Sudetic Basin. At their base, the sandy deposits of the Słupiec Formation are bounded by fine-grained lacustrine sediments known as the Upper Anthracosia Shale (Krajanów Formation); upwards, they pass into the Walchia Shale (the upper part of the Słupiec Formation), also regarded to be of lacustrine origin. These sandstones consist chiefly of sublithic to subarkosic arenites and wackes. In places, polymictic conglomerates and fine-grained sediments, and also sublithic to subarkosic mudstones occur. These sediments form a structurally varied facies assembly, presumably fluvial in origin. An analysis of the vertical sequence of lithofacies revealed a distinct tendency towards the formation of simple cyclical sequences with the grain fining upwards and with a distinctly expressed asymmetry in favour of 'high-energy' medium- and coarse-grained facies. The oscillation tendency was marked only in 'low-energy' fine facies, which are sparsely represented in the sequence. The paleochannel analysis yielded results compatible with the outcome of the lithofacies analysis. The paleochannels are very shallow in relation to their width, and have a planar, erosional bottom configuration, and in places a terrace bank morphology. The fluvial system features described here may indicate a terminal fan environment as the possible depositional location place of the Słupiec Formation sandy sediments. The source areas were located at the S and SE margins of the Intra-Sudetic Basin, and the flow was towards the W and NW towards its centre, to shallow inland basins, probably of a playa type. The red colour of the sediments may be indicative of arid or semi-arid climatic conditions in this environment during the Middle Rotliegendes .