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Evolution of the Bystrej Valley caves (Tatra Mts, Poland) based on corrosive forms, clastic deposits and U-series speleothem dating

Kicińska D., Hercman H., Najdek K.

Annales Societatis Geologorum Poloniae

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2017

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Vol. 87, No. 1

101--119

EN

The origin and age of cave deposits, as well as palaeogeographical changes in the Bystrej catchment during the last ca. 250 ka, were reconstructed in Magurska, Kasprowa Niżnia, Goryczkowa, Kalacka and Bystrej caves (the Bystrej Valley). The reconstruction is based on the study of corrosive forms, heavy mineral analyses and U-series dating of speleothems. Two generations of palaeoflows were distinguished by observations of scallops and heavy mineral analyses. In the older stage, now abandoned caves drained massifs surrounding the Bystrej Valley and part of an adjacent valley. The direction of palaeoflow changed as a result of the water capture after Kasprowa Niżnia Cave came into being. In the later stages, the evolution of cave systems was controlled by glaciation-deglaciation cycles. Probably at this time, some caves located in the lowest parts of the massifs also started to be formed. U-series speleothem dating allows the determination of five phases of speleothem deposition: ca. 220–150 ka, ca. 135–105 ka, ca. 95–70 ka, ca. 40–23 ka and during the Holocene.

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Ascending speleogenesis of Sokola Hill: a step towards a speleogenetic model of the Polish Jura

Gradziński M., Hercman H., Kicińska D., Pura D., Urban J.

Acta Geologica Polonica

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2011

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Vol. 61, no. 4

341-365

EN

The paper deals with the origin of caves in Sokola Hill (Polish Jura). The caves abound in solution cavities in the walls and ceilings, many of them arranged hierarchically, some others arranged in rising sets. Blind chimneys and ceiling half-tubes are also present. These features collectively indicate that the caves originated under Phreatic conditions by an ascending flow of water, probably of elevated temperature. Phreatic calcite spar, crystallized from water of elevated temperature, lines the cave walls. During the formation of the caves the Jurassic limestone aquifer was confined by impermeable cover. Three possible scenariosfor the origin of the caves are suggested. The firstscenario pointsto formation of the caves during the Palaeogene prior to the removal of the confining Cretaceous marls. The second connectsthe origin of the caves with regional palaeoflow driven by tectonic loading by Carpathian nappes to the south, while the third refers to local topographically driven palaeoflow. Both the second and third scenarios assume that the Polish Jura had a cover of Miocene impermeable clastics. All the scenarios account for the origin of the caves in Sokola Hill and explain the common occurrence of ascending caves throughout the Polish Jura. In the subsequentstages of evolution the caves were partly filled with various deposits. Conglomerates composed of Jurassic limestone clasts, quartz sands and sandstones are preserved as erosional remnants, locally covered by or interfingered with calcite flowstones. The clastic deposits were laid down by surface streams that invaded the caves earlier than 1.2 Ma. The caves were not invaded by water from Pleistocene glaciers, which is proved by the assemblage of heavy minerals in the cave clastics.

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Artesian origin of a cave developed in an isolated horst: a case of Smocza Jama (Kraków Upland, Poland)

Gradziński M., Motyka J., Górny A.

Annales Societatis Geologorum Poloniae

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2009

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Vol. 79, No 2

159-168

EN

The cave of Smocza Jama located in the centre of Kraków is developed in the Wawel Horst built of Upper Jurassic limestone and surrounded by grabens with Miocene clays. The cave is composed of two series: the old one has been known for ages and the new one was discovered when an artificial shaft was mined in 1974. The new series comprises small chambers separated by intervening thin walls while the old series consists of three connected together spatial chambers. The cave abounds in extensively developed solution cavities – cupolas and ceiling pockets. The internal fine-grained deposits, predominantly representing clay fraction are built of illite, mixed layer illite-smectite, kaolinite and iron oxides. They are probably the residuum after dissolution of Jurassic limestone. The cave originated in phreatic condition due to water input from below. The new series represents juvenile stage of cave evolution. The water rose through fissure-rifts located in chamber bottoms, circulated convectionally within particular chambers, finally led to bleaching of intervening walls, and hence to connection of the neighbouring chambers. The evolution of the old series is far more advanced. The rounded solution cavities imply that the cave was formed by water of elevated temperature. The lack of coarse-grained fluvial deposits, Pleistocene mammal remains and Palaeolithic artefacts prove that the cave was isolated since its inception till Holocene time. The cave originated due to artesian circulation, when the Wawel Horst was covered by imper- meable Miocene clays. A foreland basin with carbonate basement, filled with fine-grained molasse-type deposits seems to be particularly favourable for the development of artesian caves.

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Historia rozwoju dwóch torfowisk mszarnych w Borach Tucholskich

Lamentowicz M., Obremska M., Mitchell Edward A.D.

Przegląd Geologiczny

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2006

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Vol. 54, nr 1

76-80

EN

Our research confirmed the value of kettle-hole mires for reconstructing Holocene environmental changes. The multi-proxy approach in which three palaeoecological methods were used (analyses of testate amoebae, plant macrofossils and pollen) improved the interpretation potential. We studied two Sphagnum mires situated in Tuchola Pinewoods (N Poland). In Tuchola mire 9000 years of environmental changes (groundwater level and pH) were recorded. Water table changes inferred from Tuchola mire show patterns similar to regional hydrological changes recorded in Polish lakes and mires as well as in other European sites. Jelenia Wyspa mire recorded changes in local vegetation and palaeohydrology during the last 1500 years. A rise in the groundwater table, caused by deforestation in the catchment area, allowed Sphagnum to expand. Consequently, the peatland evolved into an oligotrophic mire dominated by peat mosses. Approx. 200 years ago water pH increased and subsequently decreased, the lowest value being associated with the deforestation maximum. Furthermore, the planting of pine probably also caused an acidification of Jelenia Wyspa mire.

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Palaeohydrological aspect of transformation of lakes into peat bogs during middle holocene on the basis of cladocera analysis in the northern Poland

Szeroczyńska K., Gąsiorowski M.

Studia Quaternaria

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2002

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Vol. 19

55--60

EN

Cladocera are a group of water animals, which are strongly dependent on environmental conditions. The ratio of planktonic to littoral Cladocera species is a widely used tool in palaeohydrological reconstruction of lakes' water level changes. Interpretation of this ratio is still unclear and requires further evidence. The simplest indicator of water level, which can be used in tracing lake-peat bog transitions, is the presence or absence of Cladocera and the character of its disappearance. In general, two models of Cladocera decline are observed. The first model is characterized by a very abrupt disappearance of all species, whereas the second one, with an intermediate stage, is characterized by domination of specific species. These two models are related to different types of terminal history of the water body. Even after a total disappearance of water in the peat bogs, there were episodes of some pioneer cladoceran species presence, correlated with periods of humid climate.

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Time record of palaeohydrologic changes in the development of mires during the Late Glacial and Holocene, North Podlasie Lowland and Holy Cross Mts

Żurek S., Michczyńska D. J., Pazdur A.

Geochronometria

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2002

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Vol. 21

109-118

EN

Radiocarbon dating of mire sediments is useful tool for reconstruction of time scale of wet and dry phases during the Late Glacial and Holocene. The method is applied here to determine palaeohydrological conditions of some Polish regions. On the basis of 14 C dating of sediment profiles from North Podlasie Lowland and southern piedmont of Holy Cross Mts., duration of wet (1100-1400, 2100-2600, 4700-5000, 7300-7500, 8000-8400, 8800-9200 and 10,500-10,850 BP) and dry (1700-2200, 2600-2800, 3400-3700, ca 4000 and 4500, 5100-5700, ca 6400, 6900-7100, 9200-9300, ca 10,100 and 10,900 BP) periods is suggested.