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EN
Herein are presented the results of detailed bio - (calcareous dinocysts, calpionellids, foraminifers, saccocomids) and chemostratigraphic (δ13C) studies combined with high-resolution microfacies, rock magnetic and gamma-ray spectrometry (GRS) investigations performed on the upper Kimmeridgian-upper Valanginian carbonates of the Giewont succession (Tatricum, Giewont and Mały Giewont sections, Western Tatra Mountains, Poland). The interval studied covers the contact between the Raptawicka Turnia Limestone (RTL) Fm. and the Wysoka Turnia Limestone (WTL) Fm. Their sedimentary sequence is composed of micrites, pseudonodular limestones, cyanoid packstones, lithoclastic packstone and encrinites. A precise correlation with the previously published Mały Giewont section is ensured by biostratigraphy, rock magnetic and GRS logs. The methodology adopted has enabled the recognition of two stratigraphic discontinuities, approximated here as corresponding to the latest Tithonian-early (late?) Berriasian and the early Valanginian. The hiatuses are evidenced by biostratigraphic data and the microfacies succession as well as by perturbations in isotopic compositions and rock magnetic logs; they are thought to result from a conjunction of tectonic activity and eustatic changes. A modified lithostratigraphic scheme for the Giewont and the Osobita High-Tatric successions is proposed. The top of the RTL Fm. falls in the upper Tithonian, where cyanoid packstones disappear. At the base of the WTL Fm. a new Giewont Member is defined as consisting of a basal lithoclastic packstone and following encrinites.
EN
Romania has a long history of hydrocarbon production and tens of thousands of boreholes have penetrated Miocene strata. Many well cores or cuttings have been either lost or damaged, but lab reports containing valuable petrographic, paleontological and structural data are still available. Most of the knowledge of the subsurface relies on old descriptions and interpretations used by the oil industry. These data have not been recently updated, while research results from the last decade suggest potential changes in stratigraphy, especially for the lower to middle Miocene succession. In order to update, calibrate, and reduce uncertainties regarding the subsurface stratigraphic record, we have reviewed the lab reports and used equivalent field samples for an updated interpretation of the lower to middle Miocene succession. Core and cutting descriptions from boreholes covering an area of ~10,000 km2 in the Diapir Fold Zone of the Eastern Carpathians have been selected and biostratigraphically re-evaluated based on microfossils and calcareous nannofossils. In many cases, highly uncertain ages were previously interpreted as Oligocene and early Miocene. Our recent data suggest that most of the lower Miocene is either difficult to determine or has been reinterpreted as middle Miocene (e.g., Cornu and Doftana formations). This significant change in ages requires an updated model for the timing of regional structural evolution and may open new exploration opportunities in this highly mature hydrocarbon area. This study demonstrates the need for a new complete and reliable stratigraphic framework for the whole Miocene stratigraphic record of the Eastern Carpathians.
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EN
The Indian Cave Sandstone (Upper Pennsylvanian, Gzhelian) from the area of Peru, Nebraska, USA, has yielded numerous isolated chondrichthyan remains and among them teeth and dermal denticles of the Symmoriiformes Zangerl, 1981. Two tooth-based taxa were identified: a falcatid Denaea saltsmani Ginter and Hansen, 2010, and a new species of Stethacanthus Newberry, 1889, S. concavus sp. nov. In addition, there occur a few long, monocuspid tooth-like denticles, similar to those observed in Cobelodus Zangerl, 1973, probably representing the head cover or the spine-brush complex. A review of the available information on the fossil record of Symmoriiformes has revealed that the group existed from the Late Devonian (Famennian) till the end of the Middle Permian (Capitanian).
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
Samples from the Upper Frasnian (Devonian) of Lompret Quarry and Nismes railway section in Dinant Synclinorium, southern Belgium, yielded several chondrichthyan teeth and scales. The teeth belong to three genera: Phoebodus, Cladodoides and Protacrodus. The comparison with selected Late Frasnian chondrichthyan assemblages from the seas between Laurussia and Gondwana revealed substantial local differences of taxonomic composition due to palaeoenvironmental conditions, such as depth, distance to submarine platforms, oxygenation of water, and possibly also temperature. The assemblage from Belgium, with its high frequency of phoebodonts, is the most similar to that from the Ryauzyak section, South Urals, Russia, and the Horse Spring section, Canning Basin, Australia.
EN
Tithonian (= “Middle Volgian”) carbonate rocks are exposed in Owadów-Brzezinki quarry 19 km southeast of Tomaszów Ma-zowiecki, central Poland. In the upper part of the Sławno Limestone Member, chitinoidellids have been identified in thin sections from three samples, only. Therefore, the documented part of the Chitinoidella Zone in Owadów-Brzezinki quarry is about 0.3 m thick. The identified chitinoidellid taxa suggest that this assemblage represents the Upper Tithonian Boneti Subzone. The Chitinoidella Zone occurs at the top of Unit I and correlates with the uppermost interval of the Zarajskensis Horizon (Matyja, Wierzbowski, 2016). Other microfossils identified in the Chitinoidella Zone consist of Saccocoma sp. and benthic foraminifera of the genus Planularia. Calcareous dinoflagellate cysts (Cadosina semiradiata semiradiata Wanner and C. cf. semiradiata semiradiata Wanner) occur above the chitinoidellid assemblage, in the strata corresponding to the Gerassimovi Subzone of the Virgatus Zone (Matyja, Wierzbowski, 2016). Calcareous nannofossils are extremely rare in the thin sections studied; only one small specimen was seen, identified as Rhombolithion minutum (Rood et al., 1971) Young et Bown 2014. In contrast, microbial filaments are frequently observed in the studied thin sections. Their shape and pattern are reminiscent of some recent Cyanobacteria of the order Nostocales, however the Tithonian microbial filaments are much thinner.
EN
Palaeontological data on the Caucasus are highly important for large-scale stratigraphical and palaeobiogeographical assessment of the northern Tethyan margin, but this information is often scarce and not available in English. Field studies in the Northern Caucasus have now permitted to amass some new data. Two belemnite species are described from the stratotype section of the Kamennomostskaja Formation (Callovian, Middle Jurassic) near the town of Kamennomostskij in Adygeja (Northern Caucasus). These are Belemnopsis subhastata (von Zieten, 1831) and Rhopaloteuthis ominosa Gustomesov, 1968. The latter is a rare species, and the present find allows new insights into its taxonomy. A palynological analysis of the belemnite-bearing sample was carried out, and a diverse assemblage of dinocysts, acritarchs and prasinophytes, plus pollen and spores recognised. The most abundant palynomorphs are Micrhystridium and Classopollis. Data on belemnites coupled with those on palynomorphs indicate the early Callovian age of the sample level. This interpretation differs slightly from previous conclusions based on ammonites and dinocysts. If this age is correct, the degree of condensation of Callovian deposits in the section studied was lesser than previously assumed.
EN
Foraminiferal and calcareous nannofossil assemblages from the Eastern Carpathians (northern part of the Tarcău Nappe, Romania) were documented and correlated in order to reconstruct the palaeonvironmental settings and provide a biostratigraphic framework of the Plopu Formation. The benthic foraminiferal assemblages are dominated by flysch-type agglutinated taxa, suggesting a bathyal palaeodepth with frequent oscillations of the carbon compensation depth. The agglutinated foraminifera morphogroup analyses suggest different levels of organic matter influx and oxygenation. Both the foraminifera and calcareous nannofossil assemblages suggest a shift between the warm mid Eocene to the cooler late Eocene climate. Biostratigraphic data based on calcareous nannofossils (NP15–NP19/NNTe8–NNTe12 biozones) helped to establish the age of the formation. Four assemblages of benthic agglutinated foraminifera (Psammosiphonella cylindrica – Nothia excelsa; Paratrochamminoides spp. – Trochamminoides spp.; Karrerulina spp.– Reticulophragmium amplectens; Spiroplectammina spectabilis) correlated with calcareous nannofossil bioevents supported the placement of the mid to late Eocene transition within the Plopu Formation.
PL
Z otworów wiertniczych Trojanowice 2 i Cianowice 2 opracowano mikropaleontologicznie utwory miocenu, kredy górnej, jury górnej i stropu jury środkowej. Miocen (otwór Trojanowice 2) jest reprezentowany przez utwory ogniwa iłów spirialisowych formacji z Machowa z charakterystyczną Velapertina indigena (Łuczkowska) (późny baden) oraz przez warstwy skawińskie z Praeorbulina glomerosa (Blow) (wczesny baden). Utwory kredy górnej z uwagi na obecność w zespołach form zbliżonych do Stensioeina exculpta (Reuss) wiekowo odniesiono do późnej kredy. Utwory jury górnej zawierają trzy zróżnicowane gatunkowo zespoły mikroskamieniałości: 1 – z Protomarssonella jurassica (Mityanina) i Colomisphaera carpathica (Borza) (późny oksford), 2 – z Ophthalmidium strumosum (Gümbel) i Paalzowella turbinella (Gümbel) (?środkowy–wczesny oksford); 3 – Globuligerina oxfordiana Grigelis, Colomisphaera fibrata (Nagy) i Comittosphaera czestochowiensis Rehánek (wczesny oksford). Wapienie krynoidowe i piaskowce allochemiczne stropu jury środkowej zawierały ubogi zespół otwornic aglutynujących keloweju z Verneuilinoides minimus (Kosyreva), Protomarssonella osowiensis Bielecka et Styk i Dorothia insperata Bułynnikova. W utworach tych stwierdzono również obecność gatunku Bosniella croatica (Gušić) związanego z obszarami płytkowodnej sedymentacji węglanowej.
EN
Miocene, Upper Cretaceous and Middle/Late Jurassic sediments from the Trojanowice 2 and Cianowice 2 boreholes were studied for microfossils. Miocene sediments (Trojanowice 2 borehole only) are represented by the “Spirialis Clays” member of the Machów Formation (Late Badenian) with Velapertina indigena (Łuczkowska), and by the Skawina Beds (Early Badenian) with Praeorbulina glomerosa (Blow). Upper Cretaceous (Senonian) sediments are documented by the occurrence of forms similar to Stensioeina exculpta (Reuss). Upper Jurassic sediments contain three different assemblages: 1 – with Protomarssonella jurassica (Mityanina) and Colomisphaera carpathica (Borza) (Late Oxfordian); 2 – with Ophthalmidium strumosum (Gümbel) and Paalzowella turbinella (Gümbel) (?Middle–Early Oxfordian); 3 – with Globuligerina oxfordiana Grigelis, Colomisphaera fibrata (Nagy) and Comittosphaera czestochowiensis Rehánek (Early Oxfordian). Crinoidal limestone and allochemic sandstone of the uppermost Middle Jurassic sediments containan impoverished assemblage of agglutinated foraminifers: Verneuilinoides minimus (Kosyreva), Protomarssonella osowiensis (Bielecka et Styk) and Dorothia insperata Bułynnikova. Additionally, a typical carbonate platform foraminifer Bosniella croatica (Gušić) is observed.
EN
Well-preserved foraminiferids have been found in the Chmielnik-Grabówka section (Skole Nappe, Polish Carpathians). The Abathomphalus mayaroensis (late Maastrichtian) and Racemiguembelina fructicosa (earlylate Maastrichtian) standard planktonic foraminiferal biozones have been recognized, based on the occurrence of their respective index species. Sediments of the R. fructicosa Zone contain diatoms, which are a rare component of Cretaceous flysch microfossil assemblages in the Carpathians. The diatom frustules and some foraminiferid tests are pyritized, probably after burial in the sediment, below the redox boundary or in the oxygen-deficient microenvironment inside the frustules or tests of microfossils; the presence of trace fossils and bioturbational structures in the same bed indicate an oxygenated sea floor.
PL
Górnojurajskie utwory formacji wapieni koralowcowo-glonowych ze Swarzowa, występujące w środkowej części przedgórza Karpat, w rejonie Dąbrowy Tarnowskiej–Szczucina, zawierają liczne makroskamieniałości (m.in. skleraktinie, mszywioły, ramienionogi, algi) oraz niezbyt liczne mikroskamieniałości. Niektóre mikroskamieniałości są interesującymi wskaźnikami biostratygraficznymi. Występujące sporadycznie w wyższej części tej formacji kalpionellidy (Calpionella alpina, C. aff. alpina, Crassicolaria cf. brevis, Tintinopsella cf. carpatica) wskazują na późnotytoński wiek tych osadów (zona Crassicollaria). Być może, do tytonu należy prawie cała formacja ze Swarzowa i najniższa część leżącej wyżej formacji wapienno-dolomitycznej, muszlowcowej ze Smęgorzowa. Wyższa część formacji ze Smęgorzowa może należeć już do kredy dolnej, do beriasu.
EN
The Upper Jurassic coral-algal Swarzów Formation in the Dąbrowa Tarnowska–Szczucin area, occuring in the middle part of the Carpathian Foreland Poland contains rich macrofossils (i.e. scleractinian corals, bryozoans, brachiopods, algae) and generally sparse assemblages of microfossils. Some of the latter are interesting as a biostratigraphical tool. Thus, the presence of rare calpionellids (Calpionella alpina, C. aff. alpina, Crassicolaria cf. brevis, Tintinopsella cf. carpatica) argues for Late Tithonian age (standard Crassicollaria zone) of the upper part of this formation. It is suggested that the Swarzów Limestone Formation almost entirely represents the Tithonian, which probably reaches the lowest part of the lithostratigraphic unit of the Smęgorzów Limestone-Dolomitic Coquina Formation. The upper part of this unit may belong to the Lower Cretaceous, to Berriasian.
EN
Microfacies studies show that the Upper Jurassic-LowerCretaceousshaliow-water, carbonate sedimentsof the SE Poland are rich in microfossils that supply additional data for stratigraphical and paleoenvironmentai interpretation of formerly described subdivisions. Local equivalent of the European sponge megafacies (the Kraśnik Fm.) contains characteristic microfossils Globuligerina oxfordiana and Colomisphaera fibrata. Foraminiferal species Afoeoseptajaccardi, Labirynthina mirabilis andMesoendothyra izjumiana identified in the Upper Jurassic subdivisions (the Betżyce and Glowaczow formations) are known from Oxfordian-Kimmeridgian carbonate platforms of the Meditetranean Tethys. The transitional (Tithoman/Berriasian) characler of the peri-reefal Babczyn Fm. is documented by occurrence of foraminifera (Protopeneroplis ullragranulata, Monsalevia salevensis) and caicareous dinocysts (Carpistomiosphaera tithonica, Stomiosphaerina proxima). The ageof the siiiciclastic Cieszanów Fm. is based on theEarly Cretaceous foraminifera (Meandrospira bancilai, Pfenderina neocomiensis, Stomatostoecha condensa) and caicareous dinocysts (Carpistomiosphaera valanginiana, Colomisphaera conferta, Stomiosphaera wanneri).
PL
Badania mikrofacjalne utworów górnej jury i dolnej kredy południowo-wschodniej Polski wykazały, że utwory te zawierają liczne mikroskamieniałości, w sposób znaczący uzupełniające interpretacje wiekowe i paleośrodowiskowe wydzieleń litofacjalnych. Lokalny odpowiednik europejskiej megafacji gąbkowej – formacja kraśnicka - zawiera charakterystyczne gatunki: Globuligerina oxfordiana i Colomisphaera fibrata. Stwierdzone w utworach górnej jury (formacje bełżycka i głowaczowska) gatunki Alveosepta jaccardi, Labirynthina mirabilis i Mesoendothyra izjumiana znane są z węglanowych utworów oksfordu i kimerydu śródziemnomorskiej Tetydy. Przejściowy (tyton/berias) charakter peri-rafowej formacji z Babczyna określa występowanie otwornic (Protopeneroplis ultragranulata, Monsalevia salevensis) i wapiennych dinocyst (Carpistomiosphaera tithnonica, Stomiosphaerina proxima). Wiek silikoklastycznej formacji z Cieszanowa wyznacza obecność wczesnokredowych otwornic (Meandrospira bancilai, Pfenderina neocomiensis, Stomatostoecha condensa) i wapiennych dinocyst (Carpistomiosphaera valanginiana, Colomisphaera conferta, Stomiosphaera wanneri).
EN
Palynological and micropalaeontological analysis of Middle Volgian - Lower Valanginian section from Nordvik Peninsular, a key section of Jurassic/Cretaceous boundary in Boreal regions, allows its detailed zonation (Fig. 1). The changes of taxonomical composition of the assemblages and stratigraphical position of foraminiferal and dinocyst zones have been analyzed taking into consideration two versions (A and B) of Jurassic/Cretaceous boundary. The level between Chetae-Sibiricus ammonite zones traditionally considered as Jurassic/Cretaceous boundary for Arctic regions (version A) is characterized by the lack of considerable taxonomical changes of foraminiferal assemblages. Dominant shifts and appearance of new taxa have been revealed slightly upward the section within the first ammonite zone of Boreal Berriasian. Some of foraminiferal zones are characterized by wide geographical distribution being traced over Siberia as well as Barents Sea region. They may be used for circum-Arctic correlations. Microphytoplankton assemblages also include a wide number of characteristic dinocysts taxa providing long distance correlation in some levels. The characteristic feature of Subzone Pareodinioideae, Cassiculasphaeridia reticulata, Batioladinium varigranosum is the first appearance of index species. It is also observed in the middle of Berriasian in Polar Ural Mountains, Moscow Syneclise, Arctic Canada. Paragonyaulacysta borealis(?) - Dingodinium spinosum(?) Zone is a reliable marker level for circum-Arctic correlations as the acme of Paragonyaulacysta borealis(?) in Upper Volgian-Berriasian, and the extinction of this species in lowermost Valanginian well traced over northern regions of Siberia, Barents Sea shelf, Arctic Canada and Greenland. First appearance of Dingodinium spinosum(?) in the lower part of Upper Volgian is observed in many regions of Western Europe, where it is regarded as the index of Dingodinium spinosum(?) Zone. In general the taxonomical changes of microphytoplankton assemblages are rather continuous with no considerable extinctions or diversity peaks. The most important taxonomical shift is observed near the base of Paragonyaulacysta borealis(?) - Dingodinium spinosum(?) Zone (version B). Palaeofacies analysis evidence that the richest foraminiferal assemblages are associated with the middle sublittoral, while the communities of lower sublittoral are less abundant and diverse. Sharp decrease of taxonomical diversity (2-3 species) and wide distribution of opportunist species Ammodiscus veteranus are typical for dysaerobic palaeoenvironments. The characteristic feature of Siberian microphytoplankton assemblages is low abundance and diversity of chorate and proximochorate dinocysts. The microphytoplankton associations strongly dominated by dinocysts with numerous gonyaulacaceans evidence rather deepwater and well aerated palaeoenvironments of lower sublittoral. Dysaerobic and poor aerated conditions of the same zone are characterized by the assemblages almost completely composed of prasinophytes.
EN
The Callovian to Berriasian pelagic carbonates in the Western Fore-Balkan crop out as a part of the Middle Jurassic – Lower Cretaceous peri-platform marine sediments deposited on the northern Tethyan continental margin. This pelagic record consists of marl-limestone alternation (Bov Formation), grey micritic limestones with reddish nodular limestones (Javorets Formation), Ammonitico Rosso type red nodular limestones (Gintsi Formation) and Biancone-type grey micritic regularly bedded limestones (Glozhene Formation) (Sapunov 1976). The total thickness of this succession exceeds 400 m. Rich ammonite faunas recorded from the Bov, Javorets and Gintsi Formations enabled ammonite zonation and age assignment: Macrocephalites spp., Hecticoceras spp. and Kosmoceras spp. zones (Callovian), P. athletoides, C. renggeri, P. (D.) episcopallis, P. (D.) antecedens and G. riazi zones (Oxfordian), H. beckeri zone (Upper Kimmeridgian) and H. hybonotum, S. schwertschlageri and V. rothpletzi zones (Tithonian). The stratigraphic distribution and relative abundance of pelagic microplankton organisms (thin-shelled bivalves, planktonic foraminifers, radiolarians, calcareous dinocysts, pelagic echinoderms and calpionellids) have been used for biostratigraphy and/or recognition of microbiofacies. Within the Oxfordian- Berriasian interval the calcareous dinocyst zones: C. fibrata, C. borzai, C. tithonica, P. malmica, C. tenuis, C. fortis, St. proxima and St. wanneri are recorded. The Middle Tithonian to Berriasian interval is characterized by the successive calpionellid zones: Chitinoidella, Praetintinnopsella, Crassicollaria, Calpionella and Calpionellopsis (Lakova et al. 1999). Five microbiofacies within the pelagic carbonates are superposed: mudstone and wackestone with filaments of pelagic bivalves (Callovian), Globuligerina wackestone and radiolarian wackestone [Oxfordian-Kimmeridgian(?)], Saccocoma wackestones (Kimmeridgian – Lower Tithonian) Globochaete mudstone (Middle Tithonian) and calpionellid mudstone (Upper Tithonian and Berriasian) (Fig. 1). The estimated average rate of sedimentation within the Callovian-Berriasian pelagic succession in the Western Fore-Balkan varying from 9 to 26 mm/10 3 years is characteristic for the transition from relatively condensed to stratigraphically expanded sections in the Upper Jurassic of the Tethyan region. This rate is lower during the Callovian to Kimmeridgian and increased significantly in the Tithonian and Berriasian. Probable explanations are partial carbonate dissolution of the red nodular limestones in the Late Jurassic and the increased bioproductivity of nannoplankton in the Berriasian.
EN
A coastal exposure of the Staffin Shale Formation at Flodigarry, Staffin Bay, Isle of Skye, Scotland, UK fulfils the criteria for definition as the Global Stratotype Section and Point (GSSP) for the base of the Kimmeridgian Stage (Upper Jurassic). This marine shale succession was deposited during a long-term transgression, and is part of a complete, relatively well-expanded stratigraphic succession. A rich fauna of ammonites above and below the Oxfordian/Kimmeridgian boundary allows recognition of the Evoluta Subzone (Pseudocordata Zone) and Rosenkrantzi Subzone (Rosenkrantzi Zone) of the Subboreal and Boreal uppermost Oxfordian, and the Densicostata Subzone (Baylei Zone) and the Bauhini Zone of the Subboreal and Boreal lowermost Kimmeridgian). A suitable level for the boundary is thus marked by the replacement of the Subboreal Ringsteadia (M)/Microbiplices (m) by Pictonia (M)/Prorasenia (m), and by the first appearance of Boreal Amoeboceras (Plasmatites). Detailed study of the microfossils reveals an excellent dinoflagellate succession. A variety of stratigraphically important dinoflagellates are found, the assemblages being intermediate in character between Boreal and Subboreal ones. The magnetostratigraphic data, though rather troublesome to extract, shows a polarity pattern which can be confidently correlated to other UK boundary sections. The upper boundary of a normal magnetozone falls at, or very near, the proposed Oxfordian/Kimmeridgian boundary. The 87Sr/86Sr ratio at the boundary, based on an analysis of belemnites, lies between 0,70689 and 0,70697, averaging 0.70693. Matching worldwide trends, no distinct change in the ratio is seen across the boundary. A lack of variations in the carbon isotope composition of belemnites across the Oxfordian/Kimmeridgian boundary does not indicate perturbation in the global carbon cycle. However, high ?13C values and their scatter suggest the influence of local fractionation affecting isotope composition of dissolved inorganic carbon (DIC) in the partly isolated Boreal sea. A fall in the belemnite ?18O values in the Upper Oxfordian and Lower Kimmeridgian compared to the Mid Oxfordian suggests a slight rise in seawater temperature.
EN
Deep water lowermost Cambrian sedimentary successions, Yangtze Plate, China, contain a variety of organic (acritarchs) and siliceous (sponge spicules, radiolarians) microfossils, representing oceanic both plankton and benthos. Predominant rock types are dark bedded cherts and black shales, with phosphorite concretions and phosphatic limestones. Specific methods used to separate micro- fossils from those rocks include surficial or whole-rock HF and HCl-etching, but also the acetate peel method. The latter method can be successfully applied to siliceous and clay-rich lithologies. Microfossil separation methods are described and their results are shown.
PL
W pracy przedstawiono wyniki badań górnojurajskich osadów kompleksu rafowego Aj-Petri (południowo-zachodnia część Gór Krymskich; południowa Ukraina), w oparciu o nowe dane mikrofaunistyczne. Obok mikrobialitów, głównym konstruktorem znacznych partii kompleksu rafowego Aj-Petri były pierwszy raz opisane z tego obszaru mikroinkrustery Lithocodium, Bacinella, Thamatoporella i Tubiphytes. Pozycja stratygraficzna rafy Aj-Petri, określana głównie na oksford a w górnej części dolny kimeryd, w oparciu o nowe dane powinna ulec modyfikacji. W osadach dominuje mikrofauna znana z kimerydu i tytonu. Zatem zasadnicza część rafy należy do kimerydu, a możliwe także, iż w górnych partiach do tytonu.
EN
The article presents new results of Upper Jurassic sediments from Aj-Petri reef complex (southwest Crimea Mountains, S-Ukraine) in relation to the new microfossils data. Besides micorbolites to the main reef-builders of extensive part of Aj-Petri reef complex belonge also microencrusters: Lithocodium, Bacinella, Thamatoporella and Tubiphytes described here for the first time. Stratigraphic position of Aj-Petri reef was described as oxfordian and in the upper part of buildups - lower kimmerydgian. In relation to the microfossils observation the startigraphic position should be modyfied. The main part of the reef belongs to kimmerydgian and its upper part probably to tithonian.
PL
Badania mikropaleontologiczne próbek ,,kwarcytów" z Tarczyna (Góry Kaczawskie) wykazały źle zachowane fragmenty flory oraz fauny szkieletowej. Wstępne wyniki oznaczeń mikropaleontologicznych wskazują, że metapsamity z tzw. " kwarcytów " Tarczyna są młodsze niż kambr.
EN
During the micropalaentological studies of "quartzites" occurring near Tarczyn village (Kaczawskie Mts.), the poorly preserved relics of organic matter resembling flora filaments and skeleton fragments have been ascertained first time. The preliminary results of micropalaeontological determinations indicate, that metapsamites included in Tarczyn "quartzite" Unit are younger than Cambrian.
19
Content available remote The Early Famennian recovery of phoebodont sharks
EN
Early Famennia microvertebrates from the Cape Fortune Member, Parry Islands Formation, of the Beverley Inlet area of Melville Island, Arctic Canada, comprise the teeth and possible scales of a new phoebodontid shark, Phoebodus rayi sp.n., of a protacrodont shark, Protacrodus aequalis IVANOV, and rare teeth of other sharks. The new phoebodont from the early Famennian crepida Zone is closely related to the Lazarus taxon, Ph. typicus GINTER & IVANOV. Ph. typicus emerges in the early Famennian Late triangularis Zone following the phoebodont shark hiatus subsequent to the Kellwasser Event which apparently caused extinction of most earlier phoebodonts.
EN
Recent investigations of the calcareous nannoplankton, small foraminif era and dinoflagellata has thrown additional light on the age and environment of deposition of the Paleogene deposits of the Podhale Basin. Large and small foraminifera indicate for the Nummulite Eocene Bartonian-early Priabonian age and accumulation in different ernvironments of the shallow carbonate platform. Planktic foraminifera from the uppermost slope grey marls indicate P15-PI6 zone while calcareous nannoplankton data are inconsistent indicating NP16-NP17 or 19/20 coccolith zones. The turbidite deposits of the Podhale flysch accumulated predominately during the Oligocene.
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