Wyniki wyszukiwania - Biblioteka Nauki

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Evolution of depositional systems and sedimentary cycles in Želiezovce Depression of the Danube Basin

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Rybar S. , Sarinova K. , Sujan M. , Halasova E. , Hudackova N. , Zlinska A. , Kovac M. , Kovacova M. , Ruman A. , Ledvenyiova L.

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2015

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tom Vol. 41, no. 1

129

EN

Five deep wells (Pozba4, Pozba3, Dubnik1, Nová Vieska1, Modrany1), drilled in the Želiezovce depression of the south-east Danube Basin penetrate the Cenozoic sedimentary record in overall thickness ranging from 1000 m up to 3000 m. The total thickness gradually increases from South to the North. This area is well known for the complex geological structure related to the Central Western Carpathians and Transdanubian Range junction along the Hurbanovo – Diösjenö line. Many authors have studied this area in the past, nevertheless depositional systems, sedimentary cycles and the development of sedimentary facies were never understood in detail. The re-evaluation of biostratigraphy, paleoecology, sedimentology and the reinterpretation of e-logs were all incorporated into well correlations, what resulted in definition of four main sedimentary cycles: (1) the lowermost Oligocene cycle, consisting of mudstones with occasional sandstone intercalations, associated with slope to offshore marine environment. The age is supported by the presence of the NP 22 calcareous nannoplankton zone; (2) the transgressive Langhian (Lower Badenian) deposits, composed of mudstones with epiclastic volcanic material and tuffite beds were associated with nearshore to offshore environement. The age is supported by the NN4–NN5 calcareous nannoplankton zone; (3) the Serravallian (Upper Badenian-Sarmatian) cycle is composed mainly of mudstones with abundant Lithothamnium fragments associated with brackish, coastal pain environment. The age is confirmed by the NN6 calcareous nannoplankton zone and by the mass occurrence of fish scales and Ervilia dissita (Eichwald) bivalves; (4) the overlying strata represent the Tortonian-Pliocene (Pannonian-Pliocene) cycle. The strata consist mostly from claystone (lake environment) which is overlain by sandstone and siltstone layers (deltaic and alluvial plain environments). The Tortonian (Pannonian) age of the lowermost claystone is supported by finds of Dreissenidae bivalves. The Pliocene age is only inferred by superposition of the strata.

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The Wenlock-Ludlow carbon isotope trend in the Vidukle core, Lithuania, and its relations with oceanic events

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Martma T. , Brazauskas A. , Kaljo D. , Kaminskas D. , Musteikis P.

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2005

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tom Vol. 49, No. 2

223--234

EN

A Wenlock to Ludlow terrigenous-carbonate succession in the Vidukle core in Central Lithuania represents a deep shelf environment with a general upwards-shallowing trend, interrupted by brief deepening episodes. The carbon isotope trend, based on 115 whole-rock analyses, shows three main excursions: (1) a major excursion (δ13 C values reach 3.2‰) in the lower Wenlock, (2) low shifts (1.3‰ and 1.6‰) at two levels in the upper most Wenlock Siesartis Formation corresponding to the Monograptus ludensis Biozone, (3) the most prominent excursion (δ13 C values reach 8.2‰) occurs in the upper Ludlow Mituva Fm. The upper Ludlow excursion is dated by the last occurrences of Polygnathoides siluricus below the main shift and the appearance of Ozarkodina wimani and O. crispa above the excursion. The excursion stratigraphically coincides with the Lau oceanic Event and is correlated with the mid-Ludfordian Neocucullograptus kozlowskii-Bohemograptus bohemicus tenuis Biozone. Changes in the carbon isotope trend are in general harmony with some aspects of the rock (CaO, terrigenous component) and fossil content of the section. The data presented are consistent with an arid climate model for the Ludfordian isotope event.

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The Triassic/Jurassic boundary in three contrasting facies in Hungary

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Pálfy J. , Barbacka M. , Császár G. , Demeny A. , Görög Á. , Haas J. , Götz A. , Oravecz-Scheffer A. , Ozsvárt P. , Piros O. , Ruckwied K. , Szeitz P. , Zajzon N.

Volumina Jurassica

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2006

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tom Vol. 4, no. 1

292-293

EN

Using an integrated stratigraphic approach, the Triassic/Jurassic (T/J) boundary has been studied in two different tectonostratigraphic units and three contrasting facies types in Hungary. In the northeasternmost part of the Transdanubian Range unit (part of the Alcapa terrane), the Csövár section has been intensively studied recently. Here a marine carbonate succession represents slope to basinal facies, deposited in an intraplatform basin near the margin of a Late Triassic Dachstein-type platform system. The T/J boundary is defined on the basis of ammonoid, radiolarian, conodont, and foraminiferan faunas. Paleontological data not only contribute to a biostratigraphic subdivision, but are also interpreted in the context of end-Triassic extinction and earliest Jurassic recovery of different fossil groups. A significant negative carbon isotope excursion is recorded in both carbonate and organic matter in the boundary interval. In other parts of the Transdanubian Range, a Late Triassic carbonate platform is preserved as the thick Dachstein Limestone Formation. In the Gerecse Mts. and the Tata horst, a T/J unconformity truncates the topmost Rhaetian part of the Dachstein Fm. and separates it from the overlying Hettangian strata, deposited in a deepening marine environment. Earliest Hettangian deposits and fossils are absent. A potentially more complete succession occurs farther to the west, in the Bakony Mts. Here the shallow marine carbonate deposition continues into the Hettangian, represented by the Kardosrét Limestone Fm. that overlies the Norian-Rhaetian Dachstein Fm. The lithostratigraphic boundary corresponds to the T/J boundary that marks a significant break in platform development. A disconformity and small hiatus is assumed but its duration has not yet been satisfactorily determined. A surface section on Körishegy and core material from boreholes Zt-62 (near Zirc) and Süt-28 (near Sümeg) have been investigated. The T/J boundary is marked by a sharp disappearance of Triasina hantkeni and changes in the accompanying foraminiferan and dasycladacean algal assemblage. A preliminary stable isotope study of the cores has failed to identify a negative δ ¹ ³C excursion, suggesting a hiatus at the boundary. The Mecsek Mts. in southern Hungary is part of the Tisza unit (or Tisza terrane). Here the T/J boundary falls within the coal-bearing, terrestrial to marginal marine, locally more than 1000 m thick Mecsek Formation but its precise placement has been proved difficult. Palynology offers the best potential for biostratigraphic subdivision. New palynological and paleobotanical studies are underway, aimed at a more precise palynostratigraphy and a reconstruction of climate and vegetation history in the boundary interval. In summary, the T/J boundary sections in Hungary occur in terrestrial, shallow marine (carbonate platform), and deeper marine (slope to basinal) facies. Their study provide new data towards a better understanding of the biotic and environmental changes at this critical interval of Earth history.

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The Pliocene Paludina Lake of Pannonian Basin : new evidence from northern Serbia

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Rundić L. , Vasić N. , Životić D. , Bechtel A. , Knežević S. , Cvetkov V.

Annales Societatis Geologorum Poloniae

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2016

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tom Vol. 86, No. 2

185--209

EN

This study from the Sremski Karlovci clay pit in northern Serbia sheds new light on the physicochemical conditions, ecology and evolution of the Paludina Lake – the Pliocene successor of the late Miocene giant Lake Pannon hosted by the Pannonian Basin. The multidisciplinary study combines sedimentology, sequence stratigraphy, biostratigraphy, palaeontology, palaeobotany, coal petrology, organic geochemistry and magnetic mineralogy. The sedimentary succession studied represents the lake margin at the foot of the Fruška Gora ridge. Sedimentary facies reveal minor and major lake-level changes, including a forced regression with fluvial valley incision in the succession middle part and the ultimate emergence and covering of the lake floor by Pleistocene loess. Mollusc and ostracod fauna indicates an oligohaline shallow cool-water environment, no deeper than 5–6 m, with an active inflow of spring water. The lake local depth during transgression maxima did not exceed 20 m. Palynological and geochemical analyses indicate a rich and diversified assemblage of gymnosperm plants with a contribution of angiosperms, weeds and microbial biomass in the peat-forming suboxic to oxic coastal swamp environment. Maceral analysis of organic matter shows a prevalence of huminite, accompanied richly by inertinite in lignite and by liptinite in clay. The Pleistocene shift to terrestrial semiarid environment resulted in oxidizing groundwater conditions, with the reddening of sediments around a fluctuating groundwater table and the diagenetic transformation of bacteria-derived greigite into magnetite. In regional stratigraphy, the occurrence of Viviparus neumayri Brusina in the lower half of the succession indicates the Lower Paludina Beds of Dacian Stage (early Zanclean age). Other gastropods and certain ostracodes indicate transition to the Middle Paludina Beds of lower Romanian Stage (late Zanclean–early Piacenzian). The upper half of the succession lacks age-diagnostic fossils and is considered to represent Middle Paludina Beds with a possible relic of Upper Paludina Beds at the top.

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Relationship between the abrasion of tektite clasts and their host sedimentary facies, Pleistocene, SW Poland

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Brachaniec T.

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2019

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tom Vol. 89, No. 1

83--90

EN

This study reports on the occurrence of tektite clasts with a markedly different degree of abrasion in two different fluvial facies of the Pleistocene deposits of the Nysa Kłodzka river near Paczków, SW Poland. The question addressed by the study is whether the redeposited and differently abraded tektite glass clasts derive from different distances/sources, or whether their differing degree of abrasion relates to their different host sediment as the medium of river bedload transport. Laboratory tumbling experiments are used to estimate the progress of tektite abrasion with the distance travelled within a bedload sediment of the corresponding grain-size composition. The study concludes that there is a direct relationship between the abrasion degree of tektites and their host sediment facies, but it is not simple and straight forward, as a range of specific factors comes potentially into play. Their role is discussed and is recommended to be taken into account in an abrasion experiment design and in the interpretation of experimental results. The study suggests that the tektite clasts found near Paczków were transported over a distance of about 2-4 km and were derived from denudation of the nearby Bardzkie Mts.

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Facies architecture of the Cambrian succession at the western margin of Baltica in the Podlasie region (E Poland)

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Wendorff M.

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tom Vol. 89, No. 4

453--469

EN

Sedimentary features of the Cambrian-age succession transected in seven borehole cores sited in the Podlasie region document vertical and lateral variations of shallow-marine sedimentary facies, deposited at the rifted western margin of the Baltica Palaeocontinent. The boreholes are distributed along two lines of cross-section (E–W and NE–SW) running roughly perpendicular to the margin of the palaeocontinent. The easternmost borehole represents a proximal setting located on a relatively stable, shallow basement in the east; the remaining boreholes document conditions of deposition in the subsiding shallow-marine basin, extending towards the SW. Fourteen sedimentary facies defined on the basis of their lithological and sedimentary features are interpreted in terms of the sedimentary environments they represent. Strata deposited upon the stable craton in the east document a stratigraphically condensed succession of proximal facies, 240 m thick, whereas a sequence three times thicker is positioned distally, 170 km to the west. Facies associations in the proximal section represent the lower to upper shoreface in the lower part of the section and evolve upwards to the intermediate shoreface. Facies complexes in the remaining, intermediate and distal areas form a symmetrical megasequence, composed of a positive (i.e., fining-upwards – FU) transgressive sequence, overlain by a negative (coarsening-upwards – CU) regressive sequence. The vertical arrangement of the sedimentary subenvironments during the transgression indicates a tidally influenced shoreline followed by oscillations between the swash zone, the upper, intermediate and lower shoreface, and the offshore. The symmetry of the megasequences and the rhythmic pattern of the component facies complexes indicate that the intensity of supply in the terrigenous material and the efficiency of its reworking and redistribution within the basin were similar during the transgression and the regression. The facies types and variations within the basal part of the succession reflect syndepositional movements of tectonic blocks parallel to the rifted basin margin. Differences in total thickness and facies associations between the two lines of cross-section approximately perpendicular to the basin margin indicate that sedimentation was also influenced by a synsedimentary hinge fault, extending in a WSW–ENE direction.

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Palynology, T/J boundary microfacies, clay mineralogy, C and O isotopes and other palaeoclimatic indicators from the Tatra Mts.

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Götz A. , Ruckwied K. , Biroń A. , Lintnerová O. , Michalík J.

Volumina Jurassica

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2006

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tom Vol. 4, no. 1

282-283

EN

The Furkaska and Kardolina sections expose a complete succesion of the uppermost Fatra Formation and the lowermost Kopienec Formation. The Upper Triassic Fatra Fm. is characterized by bioclastic limestones and fine-grained clastics overlain by dark claystones with intercalated sandstones (Cardinia Sandstein) of the Kopienec Formation. Due to lack of age-diagnostic index fossils, the precise position of the Triassic/Jurassic boundary is not yet known. Based on negative excursion of the δ ¹ ³C carbonate isotopic curve and microfacies analyses the boundary interval was placed near the transition of two formations. Palynological analysis was focused on palaeoenvironmental and stratigraphical aspects. Generally, the continental fraction shows a high amount of phytoclasts. The few marine organic depositional environment indicate a very shallow marine depositional environment. The palynomorph assemblage of the Fatra Fm. is characterized by numerous Ricciisporites tuberculatus. The marine fraction of this part of the sections is dominated by dinoflagellate cyst Rhaetogonyaulax rhaetica. Microflora of the Upper Fatra Formation is very similar to the Ricciisporites tuberculatus Zone of the Polish zonation and Ricciisporites-Polzdiisporites Zone of the SE Nord Sea Basin, both indicating a Middle to Late Rhaetian age. The palynomorph assemblage of the Kopienec Formation is characterized by a significant increase of trilete laevigate spores, mainly Deltoidospora spp. and Concavisporites spp. The dinoflagellate cyst Dapcodinium priscum replaces Rhaetogonyaulax rhaetica in the marine fraction. These changes may be caused by a regression at the Triassic/Jurassic boundary. Quantitative clay minerals analyses documented palaeoclimatic, palaeogeographic and postsedimentary changes in the boundary event and integrated palynological results. Mixed layer illite/smectite (I/S) smectite interlayers take about 80% of the clay fraction and their low content of smectite (10-20%) indicate relatively high diagenetic overprint of the Fatra and Kopienec formations claystones corresponding with burial temperature of 150oC. Varied contents of detrital illite, chlorite and kaolinite were used to demonstrate climatic changes in the hinterland and indicated depositional condition in this semi-restricted basin. Kaolinite and low illite/kaolinite ration indicate more humid climate during earliest Jurassic in comparison with the Rhaetian condition of illite/chlorite dominance. Peak occurrence of kaolinite at the base of the Kopienec Formation recorded different source and strong input of material from weathered and eroded land into proximal part of deltaic plain in comparison with the Fatra Formation.

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Analogue GPR study of the Permian fanglomerates from Zygmuntówka Quarry near Chęciny, Holy Cross Mountains, southern Poland, for construction of a training image for multiple point simulations

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Żuk T. , Małolepszy Z. , Szynkaruk E.

Geological Quarterly

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2018

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tom Vol. 62, No. 4

755--766

EN

The distribution of Permian alluvial fan lithofacies in a quarry at Zygmuntówka near Chęciny, Holy Cross Mts., in southern Poland was investigated using ground penetrating radar (GPR) in order to create a training image for multiple point statistics (MPS) reconstructions of alluvial fan sedimentary facies. Five pseudo-3D GPR datasets were collected, processed and uploaded for interpretation into SKUA-GOCAD 3D geological modelling software. Three radar facies were distinguished based on the 3D geometrical pattern of radar reflections and linked to lithofacies described from the quarry by Zbroja et al. (1998). A statistical summary showed that ~50% of the lithofacies resulted from gravity flows (mostly non-cohesive), while the remaining proportion was deposited by unconfined and confined flash floods. Fluvial sedimentary facies left by waning of catastrophic floods or reworking during fair weather, alihough not prevalent, could not be distinguished from confined flood deposits based only on GPR data. The GPR datasets together with information from field observations were used to carry out MPS simulations and estimate the most probable 3D model of lithofacies at the quarry scale. This model will in turn serve as a training image for MPS reconstructions of alluvial-fan facies of Rotliegend conglomerates in the multi-scale geological model of the Gorzów Block (western Poland).

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Upper Werra anhydrite [Zechstein, Upper Permian] in Poland

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Peryt T. M. , Kasprzyk A. , Antonowicz L.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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1996

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tom 44

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nr 3