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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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Evolution of Brestovská Cave based on U-series dating of speleothems

Hercman H., Gradziński M., Bella P.

Geochronometria

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2008

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Vol. 32

1-12

EN

The U-series dating indicates five episodes of flowstone growth in Brestovská Cave, namely: ca. 200 ka, ca. 128-88 ka, ca. 82-65 ka, ca. 64-50 ka, and during the Holocene. The age of flowstones and their spatial distribution within the cave prove that the upper storey of the cave was dewatered before 200 ka. At that time the lower storey also existed and was able to carry the whole water flowing through the cave. It suggests that 200 ka ago the water-table was at similar level as it is at present. Hence, one should accept that the valley bottom was then also at the present level. During at least a part of the MIS 6 the growth of speleothems was possible in the cave. It suggests that the cave was located outside the permafrost zone then. Between 50 ka and Holocene, Brestovská Cave was flooded by invasion waters originating from the melting of the Würm glacier; the water-table was additionally raised due to the blockage of a resurgence by glacifluvial sediments. The flooding event caused the destruction of older deposits, including speleothems, and deposition of fine-grained clastics on the cave walls.

3

Position and age of conglomerates in caves near Kraków (Polish Jura)

Gradziński M.

Annales Societatis Geologorum Poloniae

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1999

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Vol. 69, No. 3-4

113-124

EN

Fine-grained conglomerates have been found in five caves in the southern part of Polish Jura: Wierzchowska Górna, Nad Zródlem V, Bez Nazwy, Jama Ani, Schronisko ze Zwirem. The conglomerates are matrix-supported and are composed of dark grains, quartz grains, clasts of Upper Jurassic limestones, ferruginous clay matrix and carbonate cement. The dark grains, characteristic of the conglomerates, formed in Oxisols in tropical or subtropical climate. The soils formed in Palaeogene, probably in Eocene time. They were eroded in Oligocene or Miocene time and their physically resistant components were redeposited into caves, forming the conglomerates. Pliocene erosion removed the conglomerates nearly completely, so that only small fragments of them are preserved until now.

PL

W pięciu jaskiniach południowej części Jury Polskiej (Jaskinia Wierzchowska Górna, Jaskinia nad Źródłem V, Jaskinia bez Nazwy, Jama Ani, Schronisko ze Żwirem) stwierdzono występowanie żwirowców. Żwirowce o rozproszonym szkielecie ziarnowym składają się z: ciemnych ziarn, ziarn kwarcu, fragmentów wapieni górnej jury i ilasto-żelazistego matriks. Żwirowce spojone są węglanowym cementem. Charakterystyczne dla żwirowców ciemne ziarna są pochodzenia pedogenicznego i powstały w glebach typu Oxisol w warunkach klimatu tropikalnego lub subtropikalnego. Gleby te rozwijały się w paleogenie, zapewne w eocenie. W oligocenie lub miocenie były one rozmywane, a ich mechanicznie odporne komponenty były redeponowane w jaskiniach tworząc żwirowce. Większa część tych żwirowców uległa następnie erozji w pliocenie tak, że do dzisiaj zachowały się jedynie ich niewielkie fragmenty.