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Integrated subsurface characterisation of the Röt succession of the Bolesławiec Syncline (SW Poland): stratigraphic and tectonic constraints of the geological record

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Durkowski K. , Mastalerz K. , Fijalkowska-Mader A.

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tom Vol. 94, No. 1

83--110

EN

This study presents the first comprehensive geological analysis of the Triassic Röt sedimentary succession in the Bolesławiec Syncline (BS), North-Sudetic Synclinorium (NSS), SW Poland, and fills information gaps regarding the local lithology, stratigraphy, extent and organisation of this succession. During Triassic time, the BS was located on the southern periphery of the epicontinental Germanic (Central European) Basin. The mixed siliciclastic-carbonate Röt succession transgressively overlies the continental siliciclastics of the Buntsandstein (Bunter), locally with the occurrence of a stratigraphic gap. The Röt succession displays a complex vertical organisation with basic, about 1-m-scale, fine siliciclastic-carbonate couplets, and larger-scale sequences. The well-log profiles allow identification and provisional subdivision of the succession into several 1D sequences, 10–25 m thick, which can be correlated across the study area. The collected palynological material indicated the latest Olenekian to early Anisian age of the local Röt succession. A surprisingly strong thickness diversification of the succession, as well as its frequent incompleteness, evidenced by both palynology and correlation of well-log profiles, is interpreted in terms of local erosion, non-deposition, synsedimentary tectonic activity, and later tectonic deformation. The authors conclude that synsedimentary tectonics resulted in faulting of the area and was the principal factor responsible for differential subsidence and variable sediment accumulation rates. The lower stratigraphic interval of the Röt succession is defined explicitly by the presence of numerous and diversified small-scale soft-sediment deformational structures. The coincidental occurrence of the first marine deposits in the BS area, together with the intense soft-sediment deformation appear to indicate that the end of Early Triassic transgression was associated with intensified regional seismic/tectonic activity. The Röt sedimentary succession of the BS area also was affected by younger tectonic deformation. The pre-Cenomanian events brought about at least local uplift and limited erosion of the Röt succession. Late Cretaceous–Palaeogene inversion was responsible for the final development of the present-day structure of the NSS.

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Microbial laminites with coprolites from Upper Jurassic carbonate buildups (Kraków-Częstochowa Upland, Poland)

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Kochman A. , Matyszkiewicz J.

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tom Vol. 82, No. 4

331–-347

EN

The Upper Oxfordian microbial-sponge agglutinated to open-frame reef complex of the Zegarowe Crags in the Kraków-Częstochowa Upland originated upon an elevation of the Late Jurassic stable northern shelf of the Tethys. This elevation was formed, owing to a local decrease in subsidence rate during Jurassic time, induced by the presence of a Palaeozoic granitoid intrusion in the shelf substratum, and Late Jurassic, synsedimentary tectonics, which controlled the topography of the sea bottom. The Zegarowe Crags (Skały Zegarowe) complex at the top contains microbial laminites, composed of peloidal and agglutinated stromatolites, and intercalations of grainstones with indeterminable, favrenoid coprolites, occurring in large numbers. The development of stromatolites was associated with low nutrient availability. In contrast, the periodic activity of crabs, the main producers of the coprolites, forming the coprolitic grainstone intercalations, indicates periods, when nutrients were abundant in the sea water. The nutrinets most likely were associated with the occurrence of clouds of suspended matter, induced by gravity flows, generated by active, synsedimentary tectonics. The results of isotopic studies do not support the presence of warm, mineralizing solutions, connected with synsedimentary tectonics during development of the Zegarowe Crags complex in the Late Jurassic.

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Olistolity w formacji beloweskiej (fm) w dolinie Kamienicy jako rezultat synsedymentacyjnego skracania zbiornika magurskiego (Karpaty fliszowe)

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Bromowicz J.

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tom T. 24, z. 1

19-49

PL

Olistolity utworów formacji magurskiej (fm) i żeleźnikowskiej (fm) tkwiące wśród osuwiskowo zaburzonych skał formacji beloweskiej są odsłonięte w dolinie Kamienicy między Nową Wsią a Maciejową. Ich objętości sięgają tysięcy m sześciennych. Kształty olistolitów wskazują na ich formowanie się w trakcie spływów grawitacyjnych nie w pełni zdiagenezowanego materiału. Ich inwentarz sugeruje równoczesną sedymentację w niezbyt oddalonych fragmentach zbiornika, gruboławicowych piaskowców, margli i pakietów głównie łupkowych. Ruch tych utworów przebiegał w kierunku nachylenia paleoskłonu, prostopadle do aktualnej rozciągłości warstw. Może to stanowić dowód na synsedymentacyjne zwężanie zbiornika magurskiego powodujące nachylenie dna w środkowym eocenie

EN

Olistoliths of rocks belonging to both the Magura and the Żeleźnikowa formations are exposed in the Kamienica River valley between Nowa Wieś and Maciejowa, within the land-slided rocks of the Beloveza Formation. Volumes of olistoliths reach several thousands of cubic meters. Their geometry points to the formation during gravitational sliding of semi-consolidated material. Lithology suggests contemporaneous deposition of thick-bedded sandstones, marls and sets of predominantly shaly beds in the adjacent parts of the basin. Movements of this material were directed down the palaeoslope of the basin floor and perpendicularly to the recent strike of the beds. This can prove the synsedimentary narrowing of the Magura Basin which resulted in sealfloor sloping during the Middle Eocene

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The Lower Kimmeridgian of the Wieluń Upland and adjoining regions in central Poland: lithostratigraphy, ammonite stratigraphy (upper Planula/Platynota to Divisum zones), palaeogeography and climate-controlled cycles

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Wierzbowski A.

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tom Vol. 15, no 1

41--120

EN

The Early Kimmeridgian of the Wieluń Upland and adjoining regions, after the decline of sedimentation of the deep-neritic sponge megafacies (Częstochowa Sponge Limestone Fm.) and associated limestones and marls with poor benthic fauna (Pilica Fm.) during the Planula Chron, showed the subsequent development of moderately shallow-water biostromal chalky limestones with siliceous sponges and corals, replaced laterally by micritic limestones and marls (Prusicko Fm.) during the Platynota Chron and the earliest Hypse¬locyclum Chron. Towards the north and south shallow-marine carbonate platforms occurred (represented by deposits of the “oolitic” fm.), whereas towards the north-west and west deeper marine facies, represented initially by limestones with siliceous sponges (Częstochowa Sponge Limestone Fm.), and later during the Hypselocyclum Chron by bedded limestones and marls with ammonites (Burzenin Fm.) were deposited. This palaeogeographic pattern was controlled by the synsedimentary tectonics. The detailed biostratigraphical classification of the deposits studied from the Platynota to the Divisum zones, and their lithological character, enable the recognition of the primary sedimentary cyclicity by comparison with the well dated short eccentricity cycles in the coeval succession of south-eastern France. The two appendixes enclosed give the characteristics of: (1) the characteristics of the ammonite faunas especially of the families Ataxiocerati¬dae and Aulacostephanidae (where two new species are established – Balticeras samsonowiczi sp. nov., and Rasenioides glazeki sp. nov.); (2) the newly established lithostratigraphical units: the Prusicko Fm., and the Burzenin Fm., and the smaller rank units (members, beds) recognized therein.