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Facies anatomy of a progradational submarine channelized lobe complex: semi-quantitative analysis of the Ropianka Formation (Campanian-Paleocene) in Hucisko Jawornickie section, Skole Nappe, Polish Carpathians

Łapcik Piotr

Acta Geologica Polonica

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2019

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Vol. 69, no. 1

111--141

EN

This study is a detailed lithofacies analysis of the Wiar and Leszczyny members of the deep-marine Ropianka Formation (Campanian–Paleocene) exposed in the Hucisko Jawornickie section of the Skole Nappe, Polish Carpathian Flysch. The sedimentary succession (>400 m thick) represents a channelized lobe complex that prograded at the base of submarine slope. Seven sedimentary facies are recognized as a record of the principal modes of sediment deposition. Based on their stratigraphic grouping and grain-size trends, six facies associations are distinguished as representing specific sub-environments of the depositional system: distributary channels, channel-mouth lobes, channel levees, crevasses and interlobe basin plain with crevasse splays. The individual facies associations are characterized statistically and their internal facies organization is analysed by the method of embedded Markov chains to reveal the time pattern of depositional processes. The environmental changes indicated by the vertical succession of facies associations are attributed to the autogenic processes of the distributary channel shifting within an aggrading lobe area and the lateral switching of depositional lobes. Eustatic influences are likely, but difficult to ascertain with poor biostratigraphic data. The bulk basinward advance of the base-of-slope system was probably due to a pulse of the tectonic narrowing of the synclinal Skole Basin.

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Facies heterogeneity of a deep-sea depositional lobe complex : case study from the Słonne section of Skole Nappe, Polish Outer Carpathians

Łapcik P.

Annales Societatis Geologorum Poloniae

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2017

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Vol. 87, No. 4

301--324

EN

This article reports on the first detailed study of the Skole Nappe’s Ropianka Formation in the Słonne outcrop section along river San. Lithological and micropalaeontological similarities indicate that the sedimentary succession correlates with the formation’s Wiar Member of Campanian–late Maastrichtian age. The sedimentary succession, more than 140 m thick, is interpreted as a deep-marine complex of turbiditic depositional lobes and the study reveals its sedimentary anatomy. Six component facies of sediment gravity-flow deposits and their stratigraphic grouping into four facies associations are recognized, with these latter considered to represent deposits of the lobe axial zone, lateral flank zone and featheredge fringe zone, as well as an interlobe outer-fringe zone. Semi-quantitative characterization and comparison of facies associations gives insight into the succession’s sedimentary heterogeneity. Six depositional lobes superimposed upon one another are recognized in the stratigraphic succession, and their pattern of vertical stacking is interpreted in terms of dynamic stratigraphy on the basis of the upward succession of facies associations. The stratigraphic arrangement of facies associations is attributed to autogenic morphodynamic changes within the evolving depositional system, although it cannot be precluded that also eustatic and local tectonic forcing came into play. The case study sheds more light on the sedimentary environment, sediment sourcing system and spatial depositional pattern in the Late Cretaceous Skole Basin, where the aggrading seafloor apparently oscillated around the lysocline depth that could be mid-bathyal at that time.

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Zasoby ropy naftowej w III piaskowcu ciężkowickim w złożu Osobnica (jednostka śląska, polskie Karpaty zewnętrzne) - uwarunkowania sedymentologiczne

Lis P.

Przegląd Geologiczny

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2006

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Vol. 54, nr 7

597-604

EN

The study area is located in the central part of the Polish Outer Carpathians in the vicinity of Jasło. Petroleum reservoir described here is the third Ciężkowice sandstone (Upper Paleocene), composed of channel fill and depositional lobe succession. The Osobnica field is a part of an ancient deepwater fan system, referred to as the Eastern Fan. Within this system, seven sandstone packages interbedded with mudstone/fine sandstone deposits were recognized. The first, second and the third package are characterized by coarsening- and thickening-upward trends, and are interpreted as depositional lobes. The overlying four packages, each roughly 40 m thick, show upward fining and thinning and are interpreted as channel fill deposits. In the Osobnica field, the total resources are calculated at about 491 500 tons, of which some 352 600 tons of oil were exploited until 2002. Map of resource arrangement and structural modelling have indicated that the main factor controlling the distribution of hydrocarbons in the Osobnica field is the shape of the structure, whereas facies development played a subordinate role. The main part of oilfields is in the SE elevated part of the Osobnica anticline. Oil accumulated in both channel and lobe deposits, although channel fills appear to be slightly more oil prone.

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Sequences of the lithofacies and depositional intervals in the Godula Beds of the Polish Outer Carpathians

Słomka T., Słomka E.

Annales Societatis Geologorum Poloniae

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2001

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Vol. 71, No 1

35-42

EN

The Markov chains procedure was applied to the study on the sequences of lithofacies and depositional intervals in the Godula Beds (Turonian-Lower Senonian) of the Flysch Carpathians. The model (depositional) and modal (a most frequent in profile) diagrams were constructed and corresponding sequences were recognized. It was found that deposition from high-density turbidity currents of variable retardation rates was the dominating mechanism whereas the low-density turbidity currents were rather rare. The newly deposited sediments were commonly eroded by the succeeding, dense currents. Deposition processes were dominated by the two clearly separated environments: channels and depositional lobes. Their systems were subjected to frequent changes due to lateral migration caused by tectonic movements (uplift of cordilleras and subsidence of sea floor) and eustatic changes of sea level.