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EN
Seven Middle Miocene (Upper Badenian to Lower Sarmatian) sedimentary sections of the Central Paratethys, two from the Polish Carpathian Foredeep Basin (PCFB) and five from the Eastern Carpathian Foreland Basin (ECFB) of Romania and the Republic of Moldova have been analysed micropalaeontologically to better constrain the Badenian-Sarmatian Extinction Event, characterized by significant taxonomic impoverishment of both foraminifers and ostracods. Ourstudies show significant palaeoenvironmental changes in the basin including depth, salinity, oxygenation, and organic matter flux. The occurrence of moderately diverse planktonic foraminifera (Globigerina, Globigerinita, Globorotalia, Trilobatus, Orbulina, Velapertina) in the Upper Badenian deposits of the PCFB as well as in the ECFB and their rarity in the lowermost Sarmatian indicate an almost fully marine environment during the latest Badenian, followed by a significant regression and possible appearance of much more restricted marine conditions across the boundary. The taxonomic composition of the Sarmatian foraminifera, ostracoda and calcareous nannofossils indicate that during this interval the salinity fluctuated strongly, with the water regime varying from brackish to normal marine. In addition, the identified micropalaeontological assemblages identified show palaeoenvironmental similarity across different basins of the Central Paratethys. This supports a hypothesis of possible connections during the latest Badenian between different areas of the Central Paratethys, as well as of the existence of a gateway between the Central Paratethys and the Mediterranean realm.
EN
Foraminifera and calcareous nannoplankton from the Cretaceous-Paleogene (K-Pg) transition in the Hyżne section (Outer Carpathians, south-eastern Poland) show a relatively complete biostratigraphic record. Despite the absence of the Pa Zone in turbiditic deposits of the Polish Carpathians, the planktonic foraminiferal zones of the Late Cretaceous-Early Paleogene interval are well defined, including (1) the late Maastrichtian Abathomphalus mayaroensis Zone and its equivalents, (2) the earliest Danian Guembelitria cretacea second bloom Zone (P0 Zone), and (3) the top of the early Danian Parasubbotina cf. pseudobulloides (P1a) Zone. The foraminiferal events recorded in the studied section at the K-Pg transition are stratigraphically important. They include: (1) the interval with A. mayaroensis occurrence, (2) the interval with gradual disappearance of planktonic foraminifera from the most complex K-strategy forms, through the less specialized species to the large Heterohelicidae turnovers, and (3) the G. cretacea first and second blooms. Furthermore, the bloom of the opportunistic, benthic Bolivinita sp., the size reduction event, and the dissolution of the tests of the planktonic foraminifera are recorded. The K-Pg interval bioevents can be useful for better stratigraphic resolution of the flysch deposits of the Outer Carpathians. The nannoplankton event is represented by the appearance of Cruciplacolithus primus, which marks the onset of the return to more stable environmental conditions after the perturbations at the K-Pg boundary. The K-Pg boundary occurs within dark grey marly mudstones, above the upper boundary of the G. cretacea first bloom, and above the highest occurrence of the agglutinated foraminifera Goesella rugosa, at the top of the nannofossil CC 26 Zone, and below the deep-water agglutinated foraminifera (DWAF) dominance. The foraminiferal assemblages derive from different bathymetric zones corresponding to (1) the upper bathyal zone in the late Campanian (nannoplankton CC 22 Zone) and early late Maastrichtian (A. mayaroensis Zone), (2) the shelf margin in the latest late Maastrichtian (CC 26 nannoplankton Zone, G. cretacea first bloom), (3) the shelf margin in the earliest Danian (G. cretacea second bloom, Np1/2 Zone), and (4) the middle-lower bathyal depth, below a local foraminiferal lysocline and above CCD, in the latest early Danian (P. pseudobulloides Zone). As the foraminifera could have been redeposited by turbiditic currents, they do not necessarl ly show real bathymetric changes in the area of deposition. Such changes have not been observed in sedimentary features of the studied deposits. Foraminiferal and nannoplankton assemblages are typical of the “transitional zone” between the Tethyan and Boreal domains.
EN
The Upper Turonian to Middle Coniacian (Upper Cretaceous) succession of the Babadag Basin (North Dobrogea, Romania) constitutes an apparently continuous fossiliferous carbonate succession. The presence of moderately rich inoceramid, ammonite and foraminiferal assemblages allows for the application of a precise biostratigraphic subdivision. The palaeoenvironmental conditions and evolution of the Babadag Basin during the Late Turonian-Middle Coniacian are inferred using microfacies analysis and foraminiferal spectra. Together, these suggest the Turonian-Coniacian Badabag Basin reflects relatively shallow-water conditions in a near-shore environment, punctuated by two regression events in the Late Turonian and in the Middle Coniacian.
EN
A 250-m-thick sedimentary succession dominated by siliciclastic deposits occurs in the Kąkolówka Structure of the Skole Nappe. The succession was deposited in the inner part of the Skole Basin during the Late Cretaceous. In position and age, it corresponds to the Kropivnik Fucoid Marl of the Wiar Member (a subdivision of the Ropianka Formation), which was comprehensively described in the external part of the Skole Nappe. In this study, the authors provide the first complete data set on the lithological development and biostratigraphy of the Kropivnik Fucoid Marl from the inner part of the Skole Nappe. The results are compared to previous data from the outer part of the Skole Nappe. In the Kropivnik Fucoid Marl of the Kąkolówka Structure, three main heterolithic facies associations are distinguished: shale-sandstone, marl-sandstone and sandstone-shale. The occurrences of hard, platy and soft marls within siliciclastic rocks are typical of the sections studied. The features observed indicate a turbiditic origin of the deposits studied, including the hard, platy marls. The allogenic material of the strata described includes the small, fragile tests of planktonic foraminifera, which were redeposited from the outer parts of the Skole Basin. Particularly large concentrations of planktonic foraminifera were observed in the hard, platy marls. They are less common in the soft marls and shales. In the Zimny Dział section, a diverse assemblage of benthic and planktonic foraminifera was found. The Kropivnik Fucoid Marl was dated as uppermost Campanian to lowermost Maastrichtian on the basis of planktonic foraminifera, which represent the Gansserina gansseri Zone. The agglutinated foraminiferal assemblages are representative for the lower part of the Rzehakina inclusa Zone and the co-occurrence of the Caudammina gigantea (Geroch) acme with Rzehakina inclusa (Grzybowski) was observed.
EN
To optimize exploration for new hydrocarbon accumulations in the Polish Outer Carpathians, it is necessary to concentrate attention on identification of hydrocarbon accumulations of the “shale-gas” type. Results of recently completed analysis suggested new such possible targets in the Magura Basin, preserved in the Outer Carpathian Magura Nappe. Analysis of the preliminary results of paleoenvironmental and geochemical studies of these shales is the subject of this paper. Micropaleontological and geochemical study was conducted on the 300 m thick Świątkowa Member, the uppermost part of the Ropianka Formation located in the external, northernmost Siary Zone. This member is composed of thin- and medium-bedded sandstones interbedded by green, brown, black and dark-gray shales. Poor and changeable oxygenation is reflected in the composition of foraminiferal assemblages. A negative correlation between the TOC content and numbers and diversity of foraminifera is observed. The paleogeographic position and paleoenvironment assessment indicates that the Siary Zone fulfills certain conditions for organic productivity and preservation during the deposition of the Ropianka Formation.
EN
The succession of bioevents in planktonic foraminifer and calcareous nannoplankton communities is reviewed and summarized for the Carpathian Foredeep and northern Pannonian Basin in the time interval between ~16 and 13.5 Ma. This succession can be subdivided into three principal intervals: (1) an interval with rare Praeorbulina sicana and P. glomerosa. It was characterized by a limited immigration of index taxa linked to the lack of a warm surface water layer in the Central Paratethys. This interval can be correlated with the first Badenian transgression near the Burdigalian/Langhian boundary. The rare occurrence of biostratigraphical markers does not allow its precise dating and interregional correlation; (2) a brief interval of the first occurrences of Praeorbulina circularis, Orbulina suturalis and Helicosphaera waltrans. This can be related to the formation of a warm surface water layer suitable for the survival of orbulinas and praeorbulinas and a change from estuarine to anti-estuarine circulation. This interval can be correlated with the second Badenian transgression, which, however, was not isochronous over the area as inferred from different successions of these first occurrences; (3) a limited appearance of new index taxa in the Central Paratethys prior to the Wielician Salinity Crisis. This time interval was characterized by increased seasonality and salinity oscillations followed by climate cooling. A “reverse” migration of the stress-tolerant species Helicosphaera walbersdorfensis from the Central Paratethys to the Mediterranean is suggested. Several local bioevents with limited stratigraphic correlation potential have been recognized in this interval.
EN
The paper deals with sub-evaporite Badenian deposits (Middle Miocene, Paratethys) that display a sudden appearance of globorotaliid taxa showing preferences in the taxonomic set and coiling direction. An interval of sinistrally coiled Jenkinsella mayeri with proportionally coiled Globoconella bykovae is at the bottom of the studied sequence. It is followed by an interval of proportionally coiled Jenkinsella transsylvanica. Proportionally coiled Globoconella bykovae with a small number of proportionally coiled Jenkinsella transsylvanica are at the top of the Moravian (CPN 7) substage (Orbulina suturalis alias Lagenidae Zone). The sub-evaporite part of the Wielician (CPN 8) substage (Uvigerina costai alias Spiroplectammina Zone) began with a globorotaliid-barren interval (IIC biozone). It is followed by biozone IID displaying three globorotallid peaks amongst globorotallid-barren deposits. Only globoconellas are present in all these three events. Proportionally coiled Globoconella bykovae appeared first. It is followed by proportionally coiled Globoconella minoritesta and sinistrally coiled Globoconella bykovae at the end of the biozone IID. Coiling preferences of globorotaliids have been compared to changes in the hydrographic regime unfolding during the CPN 7 and CPN 8 in the studied area of the Paratethys. The study discovers that the coiling of globorotaliids responded selectively to the hydrographic changes. Globoconella bykovae is highly opportunistic and can tolerate considerable temperature changes. Specimens of this taxon persist to coil proportionally during the sub-evaporite Badenian, except for the shift to sinistral coiling just prior to the Wielician evaporites. Sinistrally coiled Jenkinsella mayeri is the most sensitive to hydrographic changes. This taxon retreated at the onset of the temperature drop during the mid-Moravian cryptic cooling. This cooling is marked by the new jenkinsellid occurrence – proportionally coiled Jenkinsella transsylvanica. Proportionally coiled Globoconella minoritesta is present in the middle of the IID globorotaliid peaks. The globorotaliid coiling data, presented in this paper, has been calibrated to the global stratigraphy. The integrated data (foraminifera, nannofossils, oxygen and carbon stable isotopes, radiometric measurements) supports the view that the CPN 7/CPN 8 boundary is coeval to the Langhian/Serravalian one. In the Polish part of the Carpathian Foredeep, the boundary runs within the Skawina Formation.
EN
A new dataset of benthic foraminiferal assemblages from Adventfjorden (tributary fjord of Isfjorden, West Spitsbergen) was compared with the results of a study conducted by Zajączkowski et al. (2010) in Hornsund (West Spitsbergen). According to Nilsen et al. (2016), Atlantic water inflow to the Isfjorden Trough occurs more readily than to anywhere else along the shelf of Spitsbergen; thus, we compared the foraminiferal assemblages of the outwash Adventfjorden fjord, located in the Isfjorden system, with glacial Hornsund, located in southwest Spitsbergen. Despite the juxtaposition of Adventfjorden and Hornsund the data revealed varying impacts of shelf-transformed water (STW) on the benthic foraminiferal assemblages. Outer and central Adventfjorden was dominated by Adercotryma glomerata, Recurvoides turbinata and Spiroplectammina sp., reflecting the presence of STW, while abundant Melonis barleeanus in the central area of the fjord indicated a large flux of unaltered organic matter. Only the head of the fjord was dominated by the glaciomarine taxa Cassidulina reniforme and Elphidium clavatum. Foraminiferal fauna characteristic of STW-influenced environments (i.e., Nonionellina labradorica and R. turbinata) were also observed in outer Hornsund. However, the glacier-proximal taxa E. clavatum and C. reniforme were dominant throughout the fjord, demonstrating the impacts of meltwater and high sedimentation. Therefore, it is likely that in Hornsund, glacial impact is a major environmental factor, which is stronger than the influence of STW.
EN
Middle Miocene siltstones of the Skawina Formation that crop out at Wiślica, within the axial part of the Carpathian Foredeep in Poland, were analysed. The deposits studied contain numerous benthic and planktonic foraminifera, ostracods, echinoid spines, bryozoans, bivalves and otoliths. The fossils recognised document an early ‘Badenian’ (= Langhian in the Mediterranean area), or, more precisely, ‘Moravian’ age of the deposit. Palaeoecological analysis suggests normal-marine conditions with full salinity. The studied siltstones were deposited from middle–lower shoreface to lower–offshore, warm surface water and locally suboxic to dysoxic conditions in the sediment.
EN
During the Paleogene, the area of the northern Tethys was controlled by a turbidity system stimulated by diastrophic and geodynamic processes. These factors contributed to the dispersion and rapid oxygenation of organic debris. Its accumulation was a consequence of stagnant bottom water conditions that periodically occurred in the basin. In these periods, intense decomposition intensified by hydrothermal and diagenetic processes was associated with oxygen consumption and the release of greenhouse gases, which led to hypoxia and acidification. These phenomena intensified by thermal and density stratification had a major impact on the structure, evolution and distribution of biota. Stress associated with rapidly changing conditions induced by sedimentary process and upwelling resulted in the dominance of forms that colonized most sediments (Glomospira, Ammodiscus, Recurvoides, Rzehakina) and surface waters (Guembelitria, Chiloguembelina, Globanomalina, Globigerina, Cassigerinella, Catapsydrax). At the time, foraminifera were limited to low-diversified eutrophic assemblages or were mainly replaced by siliceous phytoplankton (radiolarians and diatoms). Geochemical data confirm that environmental crises in the Paleogene basin took place under changing thermal conditions that reflect global events (KTBE, PTME, EEOC and TTE). Thermal stress favouring the formation of certain minerals or rocks occasionally occurred during the Paleocene to Eocene (siderite, phosphates) and dominated in the Early Oligocene (silica).
EN
Upper Campanian–Maastrichtian sections on the western flank of the Hun Graben in the Western Sirte Basin (WSB) are displaying two major type facies based on the foraminiferal assemblages. The first one indicates open-marine to outer-shelf conditions, and is represented by numerous bathy-pelagic planktonic foraminiferal species referable to the Radotruncana calcarata, Globotruncana aegyptiaca and the lower part of the Gansserina gansseri Zone (all late Campanian).The second type facies indicates an inner-shelf environment and is represented in the middle-upper part of the Gansserina gansseri Zone (early Maastrichtian) and Racemiguembelina fructicosa (late Maastrichtian) dominated by epi-pelagic planktonic and large benthic foraminifers. Large benthic foraminiferal index species Siderolites calcitrapoides Lamarck and Omphalocyclus macroporus (Lamarck) occur in abundance by the middle–late Maastrichtian. Correlation between planktonic foraminiferal zonation and large benthic foraminiferal zonation is given. An open-marine to outer-shelf environment passed into shallower marine conditions during the late Campanian–early Maastrichtian to late Maastrichtian, then a slight deepening and again shallowing is noticed.
EN
The first comprehensive meiobenthos study was carried out in Turkey, the Southern Black Sea (Sinop) from August 2009 to July 2010. Sediment samples were collected monthly at eight stations at 3 m and 10 m water depths located on four transects. A metal push core sampler (surface area 12.56 cm2 and length 10 cm) was used to obtain the material. Meiofaunal abundance and composition were examined. The results revealed that the meiofaunal community consists of twenty five higher taxonomic groups. Four groups dominated the community: Nematoda, Harpacticoida, Foraminifera and Polychaeta. Spatial and temporal meiofaunal abundance fluctuated among stations and over time.
EN
The evolution of the Transylvanian Basin during the Early Miocene has been restored from the succession of palaeoenvironments inferred from the sedimentological trend and succession of specific foraminifera assemblages from Lower Miocene Tihău section in northwestern Transylvanian Basin. Planktonic foraminifera suggest a Burdigalian age and recorded sea-level changes, climatic and productivity events. Benthic foraminifera offered valuable data on the palaeoenvironmental evolution, with a large-scale progradational (coarsening up) sedimentary succession influenced by regional tectonics. The succession of depositional events include: i) transgressive coarse grained deposits with typical mediterranean assemblages of bivalves in beach environments; ii) the glauconitic facies which can be associated to the maximum flooding surface of the transgression; iii) the sedimentation continued on a narrow shelf influenced by deltas during the highstand; iv) influence of regional tectonics and subsequent filling with turbidites associated to fan deltas.
EN
Mainly pelagic/hemipelagic deposits of the Vezhany Nappe (Paleocene-Lowermost Oligocene Metova Formation with a high content of planktonic foraminifera) and typical flysch deposits of the Monastyrets Nappe (Paleocene-Eocene Sushmanets Formation with common agglutinated foraminifera as well as the Eocene Drahovo Formation), of the southwestern inner part of the Ukrainian Carpathians have been studied. The Parvularugoglobigerina eugubina Zone (Lower Danian), Acarinina acarinata Zone (Upper Thanetian), Morozovella subbotinae Zone and Morozovella aragonensis Zone (Ypresian), Acarinina bullbrooki Zone and Acarinina rotundimarginata Zone (Lutetian), Subbotina corpulenta Zone and Subbotina vialovi Zone (Upper Priabonian – Lower Rupelian) based on planktonic foraminifera as well as the Rzehakina fissistomata sensu lato Zone (Paleocene), Glomospira charoides–Recurvoides smugarensis Zone (Ypresian), and an assemblage with Haplophragmoides parvulus (latest Mid Eocene-early Late Eocene) based on agglutinated foraminifera have been identified in these deposits. The deep-water agglutinated foraminifera of the “Rzehakina”, “Rhabdammina” and “Paratrochamminoides” assemblages found in the typical flysch deposits of the Sushmanets Formation indicate lower slope to abyssal environments below the CCD. The generic composition and morphological features of planktonic and benthic foraminifera recovered from marls of the Metova Formation suggest pelagic/hemipelagic conditions at bathyal depths above the foraminiferal lysocline.
EN
The present paper discusses foraminiferal assemblages and biozones established on the basis of studies of samples from ten borehole sequences of the Khanty-Mansiysk Horizon in the Samotlor area of the northern palaeobiogeographical district of western Siberia (Russia). In this region, middle and late Albian foraminiferal assemblages were first distinguished in western Siberia. Levels from which these assemblages have been recovered, are here referred to the following foraminiferal zones, the Ammobaculites fragmentarius–Gaudryinopsis filiformis Zone (middle Albian) and the Ammotium braunsteini–Verneuilinoides borealis assanoviensis Zone (upper Albian). Zonal assemblages are dominated by representatives of the orders Ammodiscida, Textulariida and Ataxophragmiida. Species of the ataxophragmiid genera Verneuilinoides, Pseudoverneuilina and Gaudryinopsis are the most characteristic, inclusive of several key index forms. Foraminiferal tests consist of agglutinated quartz-silica, the wall microstructure being almost exclusively medium and coarse grained. In specific composition, the Albian assemblages from the Samotlor area are similar to those from Transuralia (Russia) and to the Canadian Province, which, together with West-Siberian Province, forms the Arctic palaeobiogeographical realm.
EN
The sedimentation of Hieroglyphic beds of the Silesian Nappe took place between the Lower and Middle Eocene and Upper Eocene within the Carpathian Silesian Basin. These beds are represented by thin-bedded flysch containing – at various stratigraphic positions – sandstone-less complexes with variegated shales and bentonite laminae developed in conditions of calm sedimentation with a limited supply of material from the land. The profiles of Hieroglyphic beds of the Silesian Nappe are diversely developed. Their variability and borderline sequences, transitory into overlying and underlying divisions, are presented. In the Ypressian, during the sedimentation of Hieroglyphic beds, foraminiferal associations with numerous small sized Trochammina developed, which formed in the Silesian Basin after the PETM crisis. Since the Lutetian, in slightly more favourable conditions, more differentiated associations have occurred, with Reticulophragmium amplectens (Grzybowski), Ammodiscus (Dolgenia) latus (Grzybowski), and Reticulophragmium gerochi Neagu et al., which preferred cool waters, being index fossils for stratigraphy. Hieroglyphic beds developed during an interval of the gradually cooling climate. The gradual decrease in temperature stimulated the transfer of species: in the Eocene associations of Hieroglyphic beds a number of thermophilous forms, whose optimum of development came in the Upper Cretaceous-Paleocene, disappeared whereas new species appeared which prefer cold waters commonly occurring in boreal basins. The deep restructuring of foraminiferal assemblages took place in the Priabonian, when massive numbers of calcareous benthonic and planktonic forms occurred.
EN
Multiproxy sedimentological, gamma-spectrometric, foraminiferal, calcareous nannoplankton, and otolith data were used for the reconstruction of the Badenian (Middle Miocene) history of the Moravian part of the Carpathian Foredeep. The study material originated from the new borehole LOM-1, which drilled >20 metres of monotonous clayey siltstones with exceptionally rich and well-preserved microfossil assemblages. Distal parts of the Carpathian Foredeep (a forebulge depozone) are exposed in this succession. Generally, a quiet environment of outer shelf to upper bathyal of monotonous clayey silts was interpreted, which is typical for the proximal parts of a peripheral foreland basin. The section studied can be subdivided into six intervals, confirming the cyclical character of Middle Miocene sedimentation in the Central Paratethys. Interannual oscillations of nutrient content, temperature and/or salinity are interpreted based on the oscillations of geochemical as well as palaeobiological data. The turnover connected with the initiation of the Middle Miocene Climatic Transition is recorded above the LO (last occurrence) of Helicosphaera waltrans in agreement with previous observations in the Carpathian Foredeep. The changes include cooling, a decrease in nutrients, a probable increase of the salinity of surface water, and increase of seasonality. Seasonality was manifested by an alternation of mixed and stratified water columns with a seasonal input of nutrients. Concerning nutrients, sources of seasonal riverine input or seasonal upwelling are both possible.
EN
Based on geological field mapping, analyses of cores from explanatory wells, and foraminiferal age control data, we have differentiated a few types of mélanges and broken formations at the bordering zone between the Magura and Silesian nappes (Gorlice area in the Polish Outer Carpathians). These mélanges and broken formations differ in composition and structure due to different settings and processes of their formation. Several levels of broken formation within the uppermost part of the Krosno Beds were formed as mass-transport deposits at the southern slope of the Silesian Basin. They may record tectonic pulses related to advancing accretionary wedge within Magura area and directly predate the stage of the larger-scale sedimentary mélange formation at the front of the wedge. This mélange is composed mainly of the material representing the Magura succession (Siary Subunit) and the Krosno type sediments of the Silesian succession. It was emplaced within the Silesian basin in the Early Miocene time. The so-called “Harklowa peninsula”, whose geological structure has been the subject of discussions and various interpretations in the past years, is built of this type of mélange. The other recognized type of broken formation and mélange represents the chaotic bodies formed at the base of the Magura Nappe.The results of our studies contribute to better understanding of the structural evolution of this part of the Outer Carpathians
EN
The Upper Campanian–Lower Maastrichtian interval of the Middle Vistula River Valley section records the following benthic foraminiferal bioevents in ascending stratigraphical order: LO of Globorotalites michelinianus, FO and LO of Globorotalites emdyensis (=G. hiltermanni), FO of Bolivina incrassata, FO of Bolivinoides miliaris, FO of Angulogavelinella gracilis (=A. bettenstaedti), LO of Gavelinella monterelensis, FO of Osangularia navarroana, FO of Bolivina decurrens and FO of Neoflabellina reticulata. These events are recorded in very similar stratigraphic positions in the Lägerdorf-Kronsmoor succession (northern Germany) and in the succession of eastern England and, at least some of them, in eastern Europe. Accordingly they can serve as important markers for stratigraphic correlation across Europe. The FOs of the planktonic species, Rugoglobigerina milamensis, R. hexacamerata and R. pennyi, in the uppermost part of the “Inoceramus” redbirdensis Zone,are very close to the Campanian–Maastrichtian boundary as defined by inoceramid bivalves (Walaszczyk, 2004) and we propose these planktonic foraminiferal bioevents as a good proxy for this boundary in temperate regions.
EN
A new finding of lustrous coal particles from the youngest flysch sediments of the Silesian Nappe, Polish Eastern Carpathians, outcropped in the Bieszczady Mountains is here presented. The coal material occurs in a 1-m thick submarine slump layer in the Kiczera Dydiowska Sandstones, which belong to the youngest part of the Krosno Beds. Coal particles are numerous (up to 16%) in a massive sandstone of the slump layer. The siliciclastic particles from these sediments are classified as material from weathered rocks of continental block or they have been recycled from post-orogenic sediments. Lustrous coal represents coaly plant fragments, which are mostly homogeneous, belonging to macerals of vitrinite group. Some coal pebbles display tree structure, typical of gelified xylites, due to impregnation of cell walls by resinite, which occurrence in this material indicates terrestrial plants producing waxes and resins. Some of gelified plant debris shows evidence of pyritization, what in the absence of inertinite macerals in coal may indicate dysoxic conditions during first decomposition processes of organic matter under water environment. Coaly-bearing slump moved down most probably from SW during Oligocene–Miocene transition time. This shows that an intrabasinal massif, as the uplifted fragment of ?Precambrian craton, which supplied large amount of siliciclastic material to the Silesian–Subsilesian basin during the lower–middle Oligocene, still existed at the end of the Oligocene.
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