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A new look at the bivalve Anomia ephippium Linnæus, 1758 from the Miocene of the Central Paratethys: anexample from the Nowy Sącz Basin in Poland

Studencka B.

Acta Geologica Polonica

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2018

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Vol. 68, no. 4

635--650

EN

For the first time, articulated shells of Anomia ephippium Linnæus, 1758, the bivalve species widely distributed in the Egerian–Late Badenian (latest early Oligocene to late middle Miocene) in the Central Paratethys, are described and illustrated. The most astonishing fact is the presence of a heavily calcified byssus that anchored the animal to hard substrates, which is still preserved inside the byssal notch. The investigated material derives from the Badenian (middle Miocene) Niskowa Formation in the Nowy Sącz Basin, a small intramontane basin situated in the Polish Outer Carpathians. Apart from articulated shells and left valves, the collected material contains some dozen of calcified byssi fixed to rigid substrate, SEM images of which are presented. Examination of the A. ephippium specimens stored in the Polish Academy of Sciences, Museum of the Earth in Warsaw revealed other Paratethyan records of anomiid calcified byssi attached to other specimens of A. ephippium. Finally, the paper provides an overview of the previous studies on the representatives of the genus Anomia Linnæus, 1758 from the Central Paratethys and its specific assignment.

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Biostratygrafia utworów miocenu środkowego w otworze badawczym Trojanowice 2 na podstawie nanoplanktonu wapiennego

Garecka M.

Biuletyn Państwowego Instytutu Geologicznego

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2014

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nr 459

33--43

PL

Celem opracowania jest rozpoziomowanie utworów miocenu środkowego w profilu Trojanowice 2 na podstawie zespołów nanoplanktonu wapiennego. W zespołach nanoplanktonu dominują gatunki długowieczne należące do Coccolithaceae i Prinsiaceae. Mniej licznie występują: Helicosphaeraceae, Sphenolithaceae i Discoasteraceae. Na podstawie oznaczonych w próbkach gatunków: Sphenolithus heteromorphus, S. abies, Helicosphaera walbersdorfensis, Discoaster exilis, Calcidiscus macintyrei, Cyclicargolithus floridanus, Reticulofenestra pseudoumbilica, Umbilicosphaera rotula oraz niewielkich rozmiarów form należących do rodzajów Reticulofenestra i Helicosphaera badane utwory odniesiono do poziomów kokolitowych NN5 i NN6 w standardowej zonacji Martiniego.

EN

The aim of the study was to establish the zonation of Middle Miocene sediments in the Trojanowice 2 borehole, based on calcareous nannoplankton investigations. Long-ranging families are dominant, representing Coccolithaceae (Coccolithus pelagicus) and Prinsiaceae (small reticulofenestrids, R. pseudoumbilica). Helicosphaeraceae (small helicosphaerids, H. kamptneri), Sphenolithaceae and Discoasteraceae, which are important for stratigraphic conclusions, occur less frequently. Based on the co-occurrence of Sphenolithus heteromorphus, S. abies, Helicosphaera walbersdorfensis, Discoaster exilis, Calcidiscus macintyrei, Cyclicargolithus floridanus, Reticulofenestra pseudoumbilica, Umbilicosphaera rotula and small forms belonging to the Reticulofenestra and Helicosphaera species, the sediments are included into NN5 and NN6 calcareous nannoplankton zones sensu Martini.

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Badenian (Middle Miocene) echinoids and starfish from western Ukraine, and their biogeographic and stratigraphic significance

Radwański A., Górka M., Wysocka A.

Acta Geologica Polonica

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2014

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Vol. 64, no. 2

207--247

EN

Echinoderms from the Badenian (Middle Miocene) of the Fore-Carpathian Basin of western Ukraine are facies restricted. The Mykolaiv Beds, stratigraphically older, yielded the starfish Astropecten forbesi (complete skeletons), two genera of sand dollars (Parascutella, Parmulechinus), and numerous other echinoids of the genera Psammechinus , Echinocyamus, Spatangus, Hemipatagus, Echinocardium, Clypeaster, Echinolampas, and Conolampas. The stratigraphically younger, calcareous Ternopil Beds yielded Eucidaris (complete coronae, isolated spines), Arbacina , Brissus, and Rhabdobrissus. Sixteen species of echinoids are distinguished and/or commented. A new brissid, Rhabdobrissus tarnopolensis sp. nov., is established. A mass occurrence of some species (Psammechinus dubius and Hemipatagus ocellatus) contrasts with that of mass aggregations (sand dollars and Echinocardium leopolitanum) by dynamic events in selected layers of proximal tempestites. Of special note is the occurrence of very small specimens, interpreted as juveniles (‘babies’) having been swept out of their restricted biotopes (‘nurseries’). Some species hitherto regarded as of Early Miocene age, and the problem of their persistence beyond the Fore-Carpathian Basin and/or migration into that basin during the Middle Miocene transgression are discussed.

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Sarmatian foraminiferal assemblages of cavern fillings in the Badenian reefs of Medobory (Polupanivka, Western Ukraine)

Peryt D., Jasionowski M.

Biuletyn Państwowego Instytutu Geologicznego

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2012

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nr 449

175--184

EN

The Middle Miocene (Upper Badenian) coralline algal reefs of Western Ukraine contain caverns (up to 1 m across) and fissures that are filled by Sarmatian deposits: marly clays, clayey carbonate sand and bioclastic, bryozoan-rich sand. These deposits often contain abundant and very well preserved calcareous benthic foraminifera; agglutinated forms have not been recorded. Foraminiferal tests quite commonly show morphological abnormalities, e.g. twin forms or tests with irregularities in size or shape in last chambers. Each of the three analysed samples is characterized by a different foraminiferal assemblage: Elphidium aculeatum assemblage, Hauerinidae assemblage and Lobatula lobatula assemblage. These assemblages are characteristic for a shallow marine environment. Low taxonomic diversity and high dominance or monospecific foraminiferal assemblages indicate generally a restricted marine environment. It seems that the increasing salinity and very high-energy environment were the most probable factors controlling the composition of the foraminiferal assemblages.

PL

Górnobadeńskie rafy koralowe zachodniej Ukrainy posiadają kawerny o przekroju do 1 m oraz szczeliny, które obecnie są wypełnione osadami sarmackimi – iłami marglistymi i zasilonym piaskiem węglanowym i bioklastycznym, często mszywiołowym. Osady te często zawierają liczne i bardzo dobrze zachowane węglanowe otwornice bentosowe; nie stwierdzono natomiast otwornic zlepieńcowatych. Dość częste są skorupki z morfologicznymi nieprawidłowościami, np. formy bliźniacze albo skorupki z nieregularnością rozmiaru lub kształtu ostatnich komór. Każda z trzech próbek zawiera inny zespół otwornicowy: w pierwszej występuje zespół z Elphidium aculeatum, druga zawiera zespół z Hauerinidae, a trzecia – zespół z Lobatula lobatula. Wszystkie te zespoły są charakterystyczne dla środowiska płytkomorskiego. Niskie zróżnicowanie taksonomiczne i wysoka dominacja lub jednogatunkowe zespoły otwornicowe wskazują na ogólnie ograniczone środowisko morskie; wydaje się, że w takich warunkach najbardziej prawdopodobnym czynnikiem warunkującym skład zespołów otwornicowych było podwyższone zasolenie i środowisko bardzo wysokoenergetyczne.

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Miocene burrows of the Ghost Crab Ocypode and their environmental significance (Mykolaiv Sands, Fore-Carpathian Basin, Ukraine)

Radwański A., Wysocka A., Górka M.

Acta Geologica Polonica

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2012

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Vol. 62, no. 2

217-229

EN

The huge lithosome of the Middle Miocene (Early Badenian) Mykolaiv Sands, developed at the external margin of the Fore-Carpathian Basin in western Ukraine, is recognized to represent a shallowing-up sequence. Special attention is paid to burrows of the Ghost Crab Ocypode which are pantropical in present-day littoral habitats. In the Stratyn section, burrows of this type become a crucial tool in the interpretation of basin bathymetry, which starts from distal offshore depths, through the foreshore, to the backshore where the Ocypode burrows record a temporary break in sedimentation. Lithification of the sand layers and the Ocypode burrows subsequently progressed in beachrock mode. The Stratyn section demonstrates that the development of submerged shoals and/or emergent parts, throughout the huge mass of the Mykolaiv Sands, is probably responsible for their great variation in thickness in western Ukraine, which has long proved difficult to explain.