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EN
The Badenian/Sarmatian boundary in the Central Paratethys has been traditionally identified by the faunal turnover recording an important environmental change possibly controlled by the change from marine to brackish conditions. The strata below the Badenian/Sarmatian boundary in the northern Carpathian Foredeep are included into the Pecten beds, and those above it into the Syndesmya beds. Foraminiferal study of the Babczyn 2 borehole which is one of the crucial sections in the northern Carpathian Foredeep, well-known for the depositional age of rhyolite tuff within the Pecten beds dated by Śliwiński et al. (2012) at 13.06 ±0.11 Ma, indicated that in fact the boundary occurs within the Syndesmya beds. This conclusion is based upon the rapid change from a stenohaline foraminiferal fauna to a euryhaline one, and the appearance of the species Anomalinoides dividens, the taxon regarded as the marker for the Sarmatian. In the Babczyn 2 and Cieszanów 1 (located ~2.5 km basinward of Babczyn 2) boreholes, Anomalinoides dividens appears 3.1–3.8 m above the replacement of stenohaline by euryhaline foraminifers. The calcareous nannoplankton study shows that the upper Badenian and the lower Sarmatian strata in the studied sections represent the NN6, undivided NN6-NN7, and NN7 zones.
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
The post-evaporitic upper Badenian (Middle Miocene) succession of the Roztocze (marginal zone of the Carpathian Foredeep Basin) consists of shallow-marine sands and organodetrital deposits. The latter, although predominantly coarse-grained, include very rare and usually very thin intercalations of fine-grained, loamy material. A few such clay layers were sampled for their palynological content in quarries at Józefów (Józefów and Pardysówka) and Żelebsko. The clay samples yielded palynological organic matter, in contrast to organodetrital limestone samples, which were barren. The palynofacies composition, both presence/absence of land-derived material and the specific composition of aquatic material, are useful for the palaeoenvironmental reconstructions of sedimentary settings. During late Badenian time, the sedimentary setting of the deposits studied was characteri- zed by proximity to the shoreline, which, however, supplied limited input of terrestrial matter, and by restricted marine conditions caused by increased salinity. During the latest Badenian, water salinity presumably underwent a further increase, leading to the collapse of the dinoflagellate floras. The frequent occurrence of reworked Palaeogene dinoflagellate cysts in upper Badenian samples and their absence from the uppermost Badenian indicate variable intensity of erosion of the epicontinental Palaeogene strata during the Middle Miocene at Roztocze.
EN
Seismic data and core from the shallow cartographic Pilzno P-7 borehole were used to construct a new model of the Carpathian orogenic front between Tarnów and Pilzno, in the Pogórska Wola area (southern Poland). The most external, frontal thrust of the orogenic wedge (the Jaśniny structure) was identified as a syn-depositional fault-propagation fold de- tached above the Upper Badenian evaporites. Its formation was controlled by the presence of mechanically weak foredeep evaporites and by the morphology of the sub-Miocene Meso-Paleozoic foreland plate (Jaśniny and Pogórska Wola palaeovalleys). The frontal zone of the Carpathian orogenic wedge (the Skole thrust sheet and the deformed foredeep deposits of the Zgłobice thrust sheet) is characterized by significant backthrusting of the foredeep succession towards the south, and by the presence of a triangle zone, with strongly deformed Upper Badenian evaporites of the Wieliczka Formation in its core. The triangle zone was formed during the latest thrusting movements of the Carpathians. An indication of the existence of the triangle zone in the vicinity of Dębica has also been provided by reinterpretation of the archive regional geological cross-section. The youngest foredeep deposits, brought to the surface above the backthrust, have been dated as Sarmatian (NN7 nannoplankton zone), which indicates that the latest thrust movements within the frontal Carpathian orogenic in the vicinity of Tarnów-Dębica took place approx. 11-10 million years ago. Thermochronological studies (AFT and AHe) indicated that the foredeep succession drilled by the Pilzno P-7 borehole has not been buried deeper than 1.5-2 km, which is compatible with reconstruction based on the seismic data.
EN
While the marine molluscs from Sarmatian deposits of the Carpathian Foredeep Basin are known in general, there is a paucity of data on the terrestrial gastropods. Recently, a rich assemblage of terrestrial snails, accompanied by freshwater species, was found in Zwierzyniec, in the north-western, marginal part of the Carpathian Foredeep. Among the 38 taxa recognised, there are 22 species found in Poland for the first time; a new clausiliid species Triloba magurkai Stworzewicz sp. nov. is described. Freshwater gastropods (nine Lymnaeidae species and two Planorbidae species) were presented elsewhere. The malacofauna comprises aquatic and typical hygrophilous elements from coastal wetland habitats, some xerophilous species from dry, open environments, and gastropods from an adjacent subtropical woodland.
EN
Analysis of previously available stratigraphic data coupled with the re-interpretation of seismic profiles calibrated by boreholes has allowed the construction of a new tectonic model of evolution of the Gdów “embayment” – a tectonic re-entrant located along the Carpathian front east of Kraków (southern Poland). This model shows that the main phase of localized fault-controlled subsidence took place in the Early Badenian and was associated with deposition of the locally overthickened Skawina Formation. Also, deposition of evaporites of the Wieliczka Formation seems to have been tectonically controlled by local basement faulting. Supra-evaporitic siliciclastic deposits have developed as a result of overall north-directed sediment progradation from the eroded Carpathian belt towards the Carpathian Foredeep. During the final stages of development of the Carpathian fold-and-thrust wedge the previously subsiding Gdów “embayment” area was uplifted and basement faults were reactivated either as reverse faults or as low angle thrust faults. Along the leading edge of this inverted structure a triangle zone developed, with backthrusting along the evaporitic level. As a result, overthickened evaporites, formed in local tectonically-controlled depressions within the area of the Gdów “embayment” area have been strongly folded and internally deformed.
PL
Do rozpoznania elementów geomorfologii sejsmicznej na zdjęciach 3D osadów miocenu rejonu Dębica—Rzeszów—Sokołów Małopolski zapadliska przedkarpackiego wykorzystano szereg atrybutów sejsmicznych oraz przestrzenną wizualizację 3D. Uzyskane wyniki wskazują na obecność w utworach dolnego sarmatu dwóch systemów podmorskich koryt. Lokalnie rozwinięty system poprzeczny ma części proksymalne ukryte pod nasunięciem stebnicko-karpackim, a w kierunku NE łączył się z systemem osiowym o rozciągłości co najmniej 40 km i przepływie w kierunku E-SE. Koryta w obu systemach wykazują niską krętość, lokalnie anastomozującą lub meandrową geometrię, a ich szerokość wynosi 0,1-0,7 km. Wypełnienia koryt i ich amalgamaty, wykazują miąższości około 5-100 m i prawdopodobnie głównie heterolitowy charakter.
EN
A number of seismic attributes derived from five, partly overlapping 3D seismic datasets, were analyzed in order to get an insight into depositional elements of Miocene strata in SE part of the Carpathian Foreland Basin. Results point out the presence of two, major submarine channel systems in lower Sarmatian deposits. A locally developed transverse system has its proximal reaches hidden beneath the Stebnik-Carpathian thrust and it merges towards NE into an axial system, min. 40 km in extent, which drained to the E-SE. Channels show generally low sinuosity, locally anastomosing to meandering patterns, and their width varies between 0.1 and 0.7 km. Channels' fills, 5-50 m thick, are probably largely heterolithic in character.
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