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The Kuchyňa tuff is found on the Eastern margin of the Vienna Basin and was formed by felsic volcanism. The Ar/Ar single grain sanidine method was applied and resulted in an age of 15.23±0.04 Ma, which can be interpreted as the age of the eruption. The obtained numerical age is in accordance with the subtropical climate inferred by the presence of fossil leaves that originated in an evergreen broadleaved forest. Furthermore, the described volcanism was connected with the syn-rift stage of the back-arc Pannonian Basin system. The sedimentological data from the underlying sandy mudstones indicate alluvial environment what confirms terrestrial conditions during deposition. Moreover, the tuff deposition probably occurred shortly before the Badenian transgression of the Central Paratethys Sea.

The Komjatice depression, situated on the Danube Basin’s northern margin, represents a sub-basin of the Neogene epicontinental Central Paratethys Sea and Lake Pannon. The paper provides an insight into the character of sediment provenance evolution by study of well cores (ZM-1, IV-1, MOJ-1, VR-1 wells). A modern combination of provenance, sedimentology and biostratigraphy together with the reported redefinition of Pannonian formations resulted in a new lithostratigraphy of the study area. Moreover, newly published volcanic rock age data were used for calibration of biostratigraphy. The overall age span of the sedimentary fill is occupied only by late Badenian–Sarmatian (Serravallian) to Pannonian (Tortonian–Messinian) strata: 1) the basal alluvial sediments of the newly defined Zlaté Moravce Formation; 2) late Badenian–Sarmatian (Serravalian) marine sediments of the Vráble-Pozba Fm., connected with tectonic opening of the depression; 3) Pannonian (Tortonian) coarse grained sediments of the Nemčiňany Fm. with an erosional base; 4) Pannonian (Tortonian–Messinian) predominantly fine-grained, basin floor to slope Ivanka Fm., sandy deltaic Beladice Fm. and predominantly muddy, alluvial Volkovce Fm. In the middle Miocene provenance is situated in Paleozoic sequences and Neogene volcanic rocks occurring currently in the NE. During the late Miocene, provenance is changed to the NNW (Tribeč Mts.), although the transport from the NE also remained.

The Ratkovce 1 well, drilled in the Blatné depocenter of the northern Danube Basin penetrated the Miocene sedimentary record with a total thickness of 2000 m. Biostratigraphically, the NN4, NN5 and NN6 Zones of calcareous nannoplankton were documented; CPN7 and CPN8 foraminifer Zones (N9, 10, 11 of the global foraminiferal zonation; and MMi4a; MMi5 and MMi6 of the Mediterranean foraminiferal zonation were recognized. Sedimentology was based on description of well core material, and together with SP and RT logs, used to characterize paleoenvironmental conditions of the deposition. Five sedimentary facies were reconstructed: (1) fan-delta to onshore environment which developed during the Lower Badenian; (2) followed by the Lower Badenian proximal slope gravity currents sediments; (3) distal slope turbidites were deposited in the Lower and Upper Badenian; (4) at the very end of the Upper Badenian and during the Sarmatian a coastal plain of normal marine to brackish environment developed; (5) sedimentation finished with the Pannonian-Pliocene shallow lacustrine to alluvial plain deposits. The provenance analysis records that the sediment of the well-cores was derived from crystalline basement granitoides and gneisses and from the Permian to Lower Cretaceous sedimentary cover and nappe units of the Western Carpathians and the Eastern Alps. Moreover, the Lower Badenian volcanism was an important source of sediments in the lower part of the sequence.

A new plant assemblage of Cerová-Lieskové from Lower Miocene (Karpatian) deposits in the Vienna Basin (western Slovakia) is preserved in a relatively deep, upper-slope marine environment. Depositional conditions with high sedimentation rates allowed exceptional preservation of plant remains. The plant assemblage consists of (1) conifers represented by foliage of Pinus hepios and Tetraclinis salicornioides, a seed cone of Pinus cf. ornata, and by pollen of the Cupressaceae, Pinaceae, Pinus sp. and Cathaya sp., and (2) angiosperms represented by Cinnamomum polymorphum, Platanus neptuni, Potamogeton sp. and lauroid foliage, by pollen of Liquidambar sp., Engelhardia sp. and Craigia sp., and in particular by infructescences (so far interpreted as belonging to cereal ears). We validate genus and species assignments of the infructescences: they belong to Palaeotriticum Sitár, including P. mockii Sitár and P. carpaticum Sitár, and probably represent herbaceous monocots that inhabited coastal marshes, similar to the living grass Spartina. Similar infructescences occur in the Lower and Middle Miocene deposits of the Carpathian Foredeep (Slup in Moravia), Tunjice Hills (Žale in Slovenia), and probably also in the Swiss Molasse (Lausanne). This plant assemblage demonstrates that the paleovegetation was represented by evergreen woodland with pines and grasses in undergrowth, similar to vegetation inhabiting coastal brackish marshes today. It also indicates subtropical climatic conditions in the Vienna Basin (central Paratethys), similar to those implied by other coeval plant assemblages from Central Europe

International chronostratigraphic chart showing division of geological time and its numerical ages is regularly updated by the International Commission on Stratigraphy (ICS). The Slovak chronostratigraphic chart has not been updated since the end of the 1980s. This paper provides an overview of standard procedures for deriving Slovak terms; introduces Slovak translation of the latest version of International chronostratigraphic chart (v2021/10), and encourages the use of the new and/or updated chronostratigraphic terminology in all publications written in Slovak language. [ABSTRACT FROM AUTHOR]

The study of pollen spectra mirrors the evolution of landscape and climatic changes in the northwestern part of Central Paratethys domain during the regional stages Karpatian–Badenian (Late Burdigalian–Langhian to Early Serravalian; NN4‐NN6 biozone). This interval includes the Miocene climatic optimum (MCO) and the Miocene climatic transition (MCT) at 14.8–12.0 Ma. Here we study the pollen record from marine strata in eight wells and sections (Hevlín, Slup, Medlov, Iváň, Lomnice, Židlochovice, Baden Soos, and Devínska Nová Ves) including a total of 92 samples. The standard pollen diagrams are simultaneously analysed using the Palaeotropical/Arctotertiary concept (P/A), synthesized diagrams, coexistence approach, and a technique allowing to reconstruct diversity of plant functional types in order to unravel climate changes and their impact on the biosphere. Warmest climate conditions supporting a diverse, thermophilous mixed mesophytic forest vegetation with a high proportion of broadleaved evergreen PFTs persisted in the neighbouring continental parts during the Karpatian to Early Badenian (NN4‐NN5 biozone) representing the MCO. Evidence for the MTC and subsequent cooling (NN5 and NN6 at ca. 14 Ma) comes from lower percentages of thermophilous and evergreen elements and higher diversity of deciduous PFTs in the ecospectra (Devínska Nová Ves, NN6 biozone). Inferred annual precipitation rates above 800 mm and the almost continuous presence subtropical swamp tree pollen point to the persistence of overall humid climate conditions in the study area. Reconstructed precipitation data and the presence of drought‐tolerant plant functional types (PFTs) point to a seasonal climate. The studied records partly show shorter term cyclic changes in climate and plant diversity related to glacial events in the Langhian. Using the proportion of broadleaved evergreen versus broadleaved deciduous tree diversity as indicator for temperature changes, several alternations of warmer and cooler phases are obvious from the record. Moreover, sedimentary facies plays an important role for quality and resolution of terrestrial signals in marine strata. [ABSTRACT FROM AUTHOR]

The Oligocene Tard and Kiscell formations represent classical source rock examples in the Hungarian part of the Danube Basin. Similar sediments recorded in the Slovak part of the Danube Basin were studied by Rock-Eval pyrolysis in this paper, while their stratigraphic position was supported by the foraminiferal and nannoplankton biostratigraphy. Result obtained from MOD-1 and MOD-2 wells show that the Oligocene sediments are immature (Tmax < 432 °C). They contain mixed kerogen type II/III as well as coaly matter and show lower hydrocarbon potential (TOC 1.38–1.57 wt %; HI 164–345 mg HC/g TOC; PP 4.60–5.59 mg HC/g rock). Composition of organic matter confirms correlation with Hungarian Kiscell Fm. The Neogene sediments are immature and have a poor petroleum potential. One exception is present in Pannonian sediments with kerogen type II/III, relatively high TOC (0.98 wt %) and hydrogen index (HI= 424 mg HC/g TOC). Fair petroleum potential (PP 4.36 mg HC/g rock) shows that some horizons (Tortonian) can be potentially perspective in the deeper buried part of the basin. [ABSTRACT FROM AUTHOR]

The problem of paleoclimate reconstruction is an extremely interesting issue, which has been repeatedly discussed in many publications. This topic engages the attention of numerous specialists in many and various scientific disciplines. Fossil plants have vast potential as a source of information about past climatic conditions in the terrestrial realm. Various methods have been developed for the extraction of climate information from fossil land plants, but only few of these methods have provided quantitative data, e.g. Leaf Margin Analysis, Leaf Area Index, CLAMP and Coexistence Approach (CA). In this study we analyzed Middle Miocene floras from Bulgaria aiming to compare the results from different methods. The fossil floras are located in the southernmost part of the Forecarpathian Basin (NW Bulgaria). Two types of models were used to obtain quantitative data about the paleoclimate characteristics in the studied area - Simple Linear Regression (SLR) and Multiple Linear Regression (MLR) model. Furthermore, CLAMP and CA were applied. The obtained results evidence overlapping of CLAMP and CA data for diverse floras, while CLAMP data tend to produce cooler estimates than those obtained with the CA. The temperatures calculated by the SLR and MLR models are more or less consistent, but only when the standard deviations are considered. Moreover, the SLR and MLR intervals have strong correlation with those obtained from the CA. This corroborates statements by other authors, that under favorable circumstances (high diversity of the fossil flora and good taxonomic resolution) the climatic resolution of the CA can be twice as high compared to Leaf Physiognomy Approaches. The results obtained from the CA have less variability, consistently with data obtained from the MLR model. A great advantage of the CA method is that the width of coexistence intervals does not depend on species richness. [ABSTRACT FROM AUTHOR]

Abstract: The Danube Basin is situated between the Eastern Alps, Western Carpathians and Transdanubian mountain ranges and represents a classic petroleum prospection site. The basin fill is known from many 2D reflection seismic lines and deep wells with measured e‐logs which provided a good opportunity for theories about its evolution. New analyses of deep wells situated in the Danube Basin northeastern margin allowed us to refine stratigraphy and to interpret various depositional systems. This also allowed us to outline changes in provenance of sediment during the Cenozoic. The performed interpretation of the Palaeogene and Neogene depositional systems also confirmed the Oligocene–Early Miocene exhumation of the basin pre‐Neogene basement. Opening and development of the Middle to Late Miocene basin depocentres above the boundary between the Western Carpathians and Northern Pannonian domain was recognized. Our analysis contributed to a better understanding of the Hurbanovo–Diösjenő fault which acts as an inherited weakness zone along the boundary of two crustal fragments with different provenance. We document various basin types stacked one on another (retro‐arc, back‐arc and extensional hinterland basin). The analysis of sediment sources reveals intricate geodynamic processes during the Eastern Alpine–Western Carpathian orogenic system collision with European platform (formation of ALCAPA microplate) and its successive tectonics escape during the Pannonian Basin System origination. [ABSTRACT FROM AUTHOR]

A comprehensive “model” of the semi-closed Central Paratethys Sea history was proposed for the entire time span of 25 Ma. Publications and datasets of the last decades were compiled and reviewed in the light of the Western Carpathian basins record, reflecting its changing palaeogeography, palaeoenvironment, and water circulation regimes. Moreover, a set of modified palinspastic palaeogeographic maps were reconstructed taking into account the enormous changes in depositional systems and sedimentary facies, reflecting the tectonic events from the Oligocene to Miocene. The study discusses possible gateways/straits assuming two way circulations, where the surface and deep water can be exchanged between the Mediterranean, Central Paratethys, and the Eastern Paratethys. It is suggested, that a good correlation between the regional Central Paratethys and the standard Mediterranean zonations based on planktic organisms can be achieved only in sequences deposited during anti-estuarine circulation regimes. Correlation of sequences deposited during the estuarine circulation of water masses becomes problematic, making hard to define above all the Early/Middle Miocene boundary. To solve problems of the regional biostratigraphy, and the definition of correlation levels between the Mediterranean, Central Paratethys, and Eastern Paratethys, the existing and new Sr-isotope dating was used as well. Dating of specific sediments of low oxic conditions or evaporitic events was also used as time horizons for the Central Paratethys. [ABSTRACT FROM AUTHOR]

The Danube Basin is situated between the Eastern Alps, Central Western Carpathians and Transdanubian Range. The northwestern embayment of the basin is represented by the Blatné depression with deposits ranked into the Langhian-Serravallian (Badenian, Sarmatian) and Tortonian-Pliocene (Pannonian-Pliocene). They are documented by the NN4, NN5 and NN6 calcareous nannoplankton zones; the CPN7 and CPN8 foraminiferal zones (equivalent to N9, N10 and N11 of global foraminiferal zones and to the MMi4a, MMi5 and MMi6 of Mediterranean foraminiferal zones) and by the mammalian zones MN9, MN10, MN13 and by Be isotopes. Sedimentation in basin began with basal conglomerates formed by local fan-deltas short before and during the initial rifting phase. Early Langhian conglomerates are composed of Mesozoic rocks derived from the sedimentary cover and nappe units of the Eastern Alps and Central Western Carpathians. The content of crystalline rocks increases upwards, which documents a continual denudation of the emerged source area (at present forming the pre-Neogene basement of the Danube Basin). The middle to late Langhian synrift stage of the basin development was accompanied by volcanic activity. Gravity transport of sediment took place on the basin slopes formed by pronounced fault activity. The basin floor reached the deep neritic zone. During the early Serravallian shelfal offshore sedimentary conditions prevailed and gradually passed into the late Serravallian regressive coastal plains with normal to brackish salinity. Tortonian transgressive sedimentation on the muddy shelves of Lake Pannon followed and was subsequently replaced by a relatively short-living deltaic environment and later by deposition on an alluvial plain. Final Pliocene to Quaternary fluvial sedimentation is characterized by gravel and sand beds. [ABSTRACT FROM AUTHOR]

The Badenian (Langhian - Early Serravallian) marine sediments from the adjacent areas within the Central Paratethys and NE part of the Vienna Basin, were studied from a palynological perspective. The pollen data document a subtropical climate during the Miocene Climatic Optimum with dominant representation of zonal vegetation being evergreen broadleaved forests. Higher differentiation of oak type pollen, increasing number of Platanus pollen and different types of herb were observed. Some thermophilous elements (especially Sapotaceae, Palmae, Mastixiaceae and Lygodiaceae) decreased and there was an increase of the warm to cold temperate zone taxa which were first registered during the Late Badenian. These findings together with a higher proportion of extrazonal vegetation (Tsuga, Picea and Abies) in the Late Badenian pollen spectra document changes due to the uplift of the Carpathian Mountain chain. [ABSTRACT FROM AUTHOR]