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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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Middle Miocene deposits in Carpathian Foredeep : facies analysis and implications for hydrocarbon reservoir prospecting

Lis P., Wysocka A.

Annales Societatis Geologorum Poloniae

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2012

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Vol. 82, No. 3

239–-253

EN

This sedimentological study was based on well cores from the Polish and Ukrainian parts of the Carpa- thian Foredeep. It revealed general heterogeneity of facies in the middle Miocene of the sedimentary succession in the basin. Fourteen sedimentary facies were distinguished and their origin was interpreted: massive, non-graded sandstones; normal-graded, massive sandstones, with and without a stratified uppermost part; hydroplastically deformed sandstones; planar-parallel-stratified sandstones; trough-cross-stratified sandstones; ripple-cross-lami- nated sandstones; heterolithic deposits, composed of thinly interlayered sandstone and mudstone; massive and laminated mudstones; and basal gypsum/anhydrite evaporites, often intercalated with mudstone. Four main modalities of vertical facies organization were recognized and attributed to the following environments: (1) the mid-late Badenian, shoal-water, evaporitic environment that preceded the latest Badenian–early Sarmatian, main phase of foredeep development; (2) a littoral, tidal environment of the inner parts of storm-influenced, coastal bays and tidal flats or possibly spit-sheltered lagoons; (3) a wave-dominated, littoral, sandy environment, considered to be shoreface, extended by waves, in front of advancing deltas; and (4) a neritic to subneritic, muddy, offshore slope, characterized by frequent incursions of tempestite and turbidite sand. The study contributed to a better understanding of the mid-Miocene depositional systems in the basin, with significant implications for ongoing hydrocarbon exploration. Interpretations of the origins of potential reservoir sandstones provided important information on their possible stratigraphic distribution in the basin fill. The potential, economic importance of stratigraphic hydrocarbon traps underscored the urgent need for a full-scale facies analysis and fully cored wells in strategic parts of the basin.

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An application of Markov chain analysis to studies on lithofacies sequences in the alluvial fans from the "Bełchatów" lignite deposit (Poland

Mastej W.

Annales Societatis Geologorum Poloniae

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2002

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Vol. 72, No 3

271-282

EN

The Markov chain analysis was used to study on lithofacies sequences in alluvial fans enclosed in the main seam of the "Bełchatów" lignite deposit. Quantitative approach supported the qualitative results of sedimentological analysis - the origin of muds, clays and coaly clays as well as the presence of a barrier (peat bog) between the fans and the lake with carbonate deposition. It was found that ephemeral lakes located on the fan surface were favourable sites for development of peat bogs. Similarly, the same lakes evolving into the peat bogs were favourable environments for expansion of sand lobes of the fans. It was discovered that cyclicity in sediment succession was disturbed by erosion. The new model of lacustrine limestone deposition was proposed for the northwestern part of lake which borders the fans from the northwest.