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EN
In the Sadowa Góra quarry in Jaworzno, southern Poland, the Muschelkalk deposits are exposed (Lower and Upper Gogolin Beds). The occurrence of echinoderms seems to be particularly interesting. The isolated ossicles of asteroids were found already in the 1st Wellenkalk of the Lower Gogolin Beds (Aegean), which is one of the oldest post-Paleozoic occurrence in the world. Until recently, it was believed that the first echinoids appeared in the Germanic Basin during the Bithynian (above the Conglomeratic Horizon of the Upper Gogolin Beds). Currently, they have been found, similarly to the remains of asteroids, already in the 1 st Wellenkalk. Attention was also drawn to the fact that the stratigraphically important crinoid species Holocrinus dubius may have appeared in Upper Silesia earlier than previously thought.
EN
Triassic and Jurassic siliciclastic rocks from boreholes drilled in the Łódź and Miechów troughs to the SW of the Mid Polish Anticlinorium have been subjected to petrologic studies. The are represented by claystones, mudstones, sandstones, and less frequently by conglomerates. The studies shows that the filtration and reservoir properties of the Triassic deposits not good due to diagenetic processes (compaction, cementation, replacement, dissolution). Only some Lower Triassic sandstones, occurring among others, as intelayers, display increased values of permeability and porosity (to about 27 vol. %). The best properties are display ed by sandstones from the Brzegi IG 1 borehole, in which macropore intergranular space is present. The Lower Jurassic rocks are characterized by the best properties within the Jurassic complex. They show increased values of mostly secondary porosity, which results from the dissolution of grains and cements. The pore space is developed homogenously. It has a micropore character in the Middle and Upper Jurassic deposits.
3
Content available Early Triassic conodonts in Western Tethys
EN
Conodonts are phosphatic, tooth-like elements of extinct jawless vertebrates that are classified in the independent class Conodonta. Due to their rapid evolution, wide palaeogeographic distribution and high resistance, conodonts are one of the most significant microfossil groups in the biostratigraphy of the Paleozoic and Triassic. Animals with conodonts were bilaterally symmetrical, exclusively marine organisms, where they inhabited a variety of habitats. These include both open sea habitats, whereas some species adapted to shallow habitats of epicontinental seas. For this reason, conodonts are extremely important for understanding of the palaeoecological and palaeogeographic conditions of the Paleozoic and Triassic. They were unquestionably one of the most successful animal groups, since they existed more than 300 million years and their elements are widely used as index fossils. Conodonts have shown their value for Triassic biostratigraphy. Based on international criteria the Permian-Triassic system boundary is defined with the first appearance of the conodont species Hindeodus parvus (Kozur & Pjatakova). The Permian-Triassic interval strata of the GSSP section in Meishan (China) are next to the platform-bearing gondolellids marked by the presence of Hindeodus-Isarcicella population that enabled to introduce also a conodont zonation for shallow facies. A standard conodont zonation is, except for the two lowermost Triassic zones, based on gondolellid genera that lived in deeper water: Clarkina, Sweetospathodus, Neospathodus, Novispathodus, Borinella, Scythogondolella, Icriospathodus, Triassospathodus and Chiosella. Certain Dienerian and Smithian strata of Western Tethys are marked by shallow water and euryhaline genera and due to the absence of global biozonation markers, a stratigraphic value of some genera (Hadrodontina, Pachycladina, Eurygnathodus, Foliella, Platyvillosus) is recognized. These shallow water genera were ecologically controlled (temperature, oxygen levels) that have been adapted to the epicontinental ramp environment and were particulary instrumental in forming the western part of the Tethyan province.
EN
Hydrocarbon generation in the Zechstein Main Dolomite and Upper Triassic potential source rocks of the Polish Basin was investigated by 1-D thermal maturity modelling in 90 boreholes across the basin. This identified major zones potentially worthy of further exploration efforts. The maximum burial depth of the Zechstein Main Dolomite and Upper Triassic reached >5 km during the Late Cretaceous leading to maximum thermal maturity of organic matter. Hydrocarbon generation development reveals considerable differences between particular zones of the Zechstein Main Dolomite and Upper Triassic. The kerogen transformation ratio (TR) in the Zechstein Main Dolomite reached values approaching 100% along the basin axis. The TR in the Upper Triassic source rocks is generally lower than in the Zechstein Main Dolomite due to lesser burial. The Upper Triassic source rocks have the highest TR values (>50%) along the basin axis, in the area between boreholes Piła IG 1 and Piotrków Trybunalski IG 1, with the most pronounced zone in the Krośniewice Trough (i.e., between the Krośniewice IG 1 and Budziszewice IG 1 boreholes), where the TR reached >90%. The Zechstein Main Dolomite and Upper Triassic entered the oil window in the Late Triassic to Early–Middle Jurassic, respectively. Hydrocarbon generation continued until the Late Cretaceous, and was completed during tectonic inversion of the basin.
EN
The beginning of exploitation of Lower Triassic (Röt, Olenekian) sandstones in Doły Biskupie dates back to the 17th century. The village is situated 12 km west of Ostrowiec Świętokrzyski, in the Świślina Valley, in the north-eastern part of the Holy Cross Mountains. In addition to sandstones, a wide spectrum of other rocks types were excavated in the adjacent areas: Lower Devonian (Emsian) sandstones in Godów, Middle Devonian (Efelian) dolomites in the Doły Opacie quarry and Lower Triassic (Middle Buntsandstein, Olenekian) sandstonesin Wióry. The last quarry at Doły Opacie was closed in 1984. The Doły Opacie and Doły Biskupie quarries currently provide a number of inanimate nature monuments.
EN
The Stormberg Group comprises the Molteno, Elliot and Clarens formations and is one of four stratigraphical groups that make up the Karoo Supergroup in South Africa. The group is the highest unit in the Karoo Basin, representing the final phase of preserved sedimentation. The major problem with the Stromberg Group is that the mode of transport, hydrodynamic energy conditions and depositional environment are still poorly understood. For the present paper, grain size and lithofacies studies on selected sandstones from the Molteno, Elliot and Clarens formations were performed so as to elucidate their textural characteristics, depositional processes, sedimentation mechanisms and hydrodynamic energy conditions and to discriminate different depositional environments. The statistical parameters of grain size distribution (mean grain size, standard deviation, skewness and kurtosis) show that the sandstones are predominantly unimodal, fine grained, moderately well sorted, mesokurtic and near symmetrical. The bivariate diagrams of the aforementioned statistical parameters demonstrate that river and aeolian dune had the greatest impact on the depositional environments. Likewise, the C-M pattern (Passega diagram) shows that the sandstones were mostly deposited through tractive current process. Furthermore, the C-M diagram reveals the prevalence of rolling, suspension and graded suspension modes of sediment transportation. Seventeen sedimentary lithofacies were identified and grouped into seven lithofacies associations. These lithofacies associations indicate braided channel, overbank and swamp deposits for the Molteno Formation, alluvial fan/floodplain and playa deposits for the Elliot Formation and aeolian deposits for the Clarens Formation.
EN
Fossil charcoal is the primary source of evidence for palaeo-wildfires and has gained increasing interest as a proxy in the reconstruction of past climates and environments. Today, increasing temperatures and decreasing precipitation/humidity appear to correlate with increases in the frequency and intensity of wildfires in many regions worldwide. Apart from appropriate climatic conditions, sufficient atmospheric oxygen (>15%) is a necessary precondition to sustain combustion in wildfires. The Triassic has long been regarded as a period without evidence of wildfires; however, recent studies on macro-charcoal have provided data indicating their occurrence throughout almost the entire Triassic. Still, the macro-palaeobotanical record is scarce and the study of micro-charcoal from palynological residue is seen as very promising to fill the gap in our current knowledge on Triassic wildfires. Here, the authors present the first, verified records of micro-charcoal from the Triassic of the Germanic Basin, complementing the scarce macro-charcoal evidence of wildfires during Buntsandstein, Muschelkalk and Keuper (Anisian-Rhaetian). The particles analysed by means of scanning electron microscopy (SEM) show anatomical features typical of gymnosperms, a major element of the early Mesozoic vegetation following the initial recovery phase after the PT-boundary event. From the continuously increasing dataset of Triassic charcoal, it becomes apparent that the identification of wildfires has a huge potential to play a crucial role in future studies, deciphering Triassic climate dynamics. The first SEM study of micro-charcoal from palynological residue spanning the entire Triassic period, presented here, is a key technique to further unravel the charcoal record as a puzzle piece in palaeoclimate reconstruction.
PL
Określanie dojrzałości termicznej palinomorf na podstawie ich barwy jest metodą powszechnie stosowaną w prospekcji węglowodorów. Kolor zewnętrznej błony miospor zmienia się na skutek podgrzania od bladożółtego po czarny w zależności od paleotemperatury. Obecnie funkcjonuje wiele skal barw palinomorf skorelowanych z wartościami refleksyjności witrynitu, maksymalną temperaturą pogrzebania i stadiami generacji węglowodorów. Ze względu na zróżnicowany zarówno pod względem taksonomicznym, jak i morfologicznym materiał autorka posłużyła się skalą TAI AMOCO. Przeanalizowano ponadto udział poszczególnych grup kerogenu w palinofacjach pod kątem ich węglowodorowego potencjału. Badaniami objęto osady górnego permu i triasu z 11 otworów wiertniczych zlokalizowanych w północnej części niecki nidziańskiej. Wykazały one, że w próbkach triasowych oraz w próbkach górnego permu z otworu Milianów IG 1 dominuje jasnożółty do pomarańczowego kolor spor i ziaren pyłku, odpowiadający indeksowi TAI od 1 do 4, czyli stadium przed generacją ropy naftowej i stadium wczesnej generacji ropy naftowej. Jedynie w próbach górnego permu z otworu Pągów IG 1 dominuje brązowy kolor miospor, który odpowiada indeksowi TAI od 4+ do 5, czyli głównemu stadium generacji ropy naftowej. Dominująca wartość refleksyjność witrynitu Ro wynosi 0,4–0,6%, a zatem stopień dojrzałości materii organicznej w utworach górnego permu i triasu jest niezbyt wysoki, co świadczy o stosunkowo niskich temperaturach diagenezy osadu (< 80°C). Z analizy palinofacji wynika, że w utworach górnego permu i triasu występuje kerogen mieszany i strukturalny. Kerogen mieszany, stwierdzony w skałach węglanowych, zawiera amorficzny kerogen drobnorozproszony i „fluffy” pochodzenia glonowego oraz kerogen strukturalny, pochodzenia terygenicznego, głównie egzynit i witrynit. Kerogen mieszany charakteryzuje się potencjałem ropnym (kerogen ropotwórczy), natomiast kerogen strukturalny – potencjałem ropno-gazowym.
EN
Determining the thermal maturity of palynomorph based on their color is a method commonly used in hydrocarbon prospecting. The color of the outer membrane of miospores (exine) changes as a result of heating from pale yellow to black depending on the paleotemperature. Currently, there are many palynomorph color scales correlated with the value of vitrinite reflectance, temperature of burial and hydrocarbon generation stages. Due to the varied material, both in taxonomic and morphological terms, the author used the TAI AMOCO scale. Furthermore, the share of individual kerogen groups in palynofacies was analyzed in terms of their hydrocarbon potential. The Upper Permian and Triassic deposits from eleven boreholes located in the north part of the Nida Basin were investigated. They showed that the Triassic and in the Upper Permian samples from the Milianów IG 1 borehole, are dominated by the pale yellow to orange color of spores and pollen grains, corresponding to a TAI index from 1 to 4, i.e. the pre-generation, dry gas and the early oil generation windows. In turn, only the samples of the Upper Permian from the Pągów IG 1 borehole are dominated by the brown color of miospores, which corresponds to a TAI index from 4+ to 5, i.e. the peak oil prone. Dominant vitrinite reflectance Ro varies from 0,4% to 0,6%, so the degree of organic matter maturity in the Upper Permian and Triassic deposits is not very high, which indicates relatively low temperatures of sediment diagenesis (< 80°C). Analysis of palynofacies showed that the Upper Permian and Triassic deposits contain mixed and structural kerogen. Mixed kerogen, occurring in carbonate rocks, contains amorphous fine-scattered kerogen and “fluffy” of algae origin, as well as structural kerogen of terrigeneous origin, mainly exinite and vitrinite. Mixed kerogen is characterized by oil potential, whereas structural kerogen – by gas-oil potential.
PL
Głównym celem artykułu jest odtworzenie szczegółów budowy strukturalnej utworów triasu i paleozoiku centralnej części przedgórza Karpat na podstawie interpretacji nowych materiałów sejsmicznych 3D. W ramach interpretacji wykonano analizę atrybutów sejsmicznych, wśród których najbardziej pomocne były: Time gain, Relative acoustic impedance, First derivative, Dominant frequency oraz Instantaneous bandwidth. Dotychczasowe informacje na temat budowy geologicznej kompleksu paleozoicznego w tym obszarze pochodziły głównie z interpretacji profili sejsmicznych 2D, koncepcji regionalnych oraz informacji z jedynego głębokiego otworu wiertniczego zrealizowanego na przełomie lat 50. i 60. XX wieku. Wyniki przeprowadzonej analizy obrazu sejsmicznego wskazują, że podłoże jury zbudowane jest z szeregu bloków tektonicznych o zróżnicowanej wielkości oddzielonych powierzchniami dyslokacji. W większości mają one charakter bloków wychylonych (tilted blocks), stanowiąc pozostałość kaledońsko-waryscyjskiego systemu tektonicznego. Utwory paleozoiczne o wyraźnie uporządkowanych ciągłych refleksach sejsmicznych silnie kontrastują w obrazie sejsmicznym z zalegającym poniżej kompleksem anchimetamorficznych skał najwyższego ediakaru o nieuporządkowanym, jednorodnym zapisie. Klastyczne utwory dolnego triasu w pierwszej kolejności wypełniają głębsze partie półrowów tektonicznych. Na podstawie analizy obrazu sejsmicznego kompleks ten podzielono na dwie serie: dolną, o zdecydowanie mniejszych wartościach amplitudy i zauważalnie mniejszej ciągłości refleksów sejsmicznych, oraz górną, o zróżnicowanej dynamice i większej ciągłości refleksów. Najwyższym analizowanym kompleksem są węglanowe utwory retu i wapienia muszlowego, cechujące się wysokimi wartościami amplitudy i dużą ciągłością refleksów, dzięki czemu są one łatwo identyfikowalne na sekcjach sejsmicznych. Przeprowadzona analiza z wykorzystaniem atrybutów sejsmicznych pozwoliła na określenie charakterystyki sejsmicznej poszczególnych kompleksów litostratygraficznych triasu i paleozoiku oraz wniosła bardziej szczegółowe informacje o budowie geologicznej obszaru badań.
EN
The main purpose of the article was to reconstruct the structural details of the Triassic and Palaeozoic formations of the central part of the Carpathian Foreland based on interpretation of new 3D seismic data. The interpretation included the analysis of seismic attributes, among them Time Gain, Relative acoustic impedance, First derivative, Dominant frequency and Instantaneous bandwidth were the most useful. Previous knowledge on the geological structure of the Palaeozoic complex in this area was derived mainly from the interpretation of 2D seismic sections, regional concepts and data from the only deep well drilled in the late 1950s and early 1960s. The results of the seismic image analysis show that the Jurassic sub-surface is composed of a number of tectonic blocks of various sizes, separated by dislocation zones. Most of them are tilted blocks which are the remnants of the Caledonian-Variscan tectonic system. Palaeozoic sediments with clearly arranged continuous seismic reflectors strongly contrast in the seismic image with the complex of anchimetamorphic rocks of the uppermost Ediacaran characterized by disarranged, homogeneous record. Clastic formations of the Lower Triassic fill primarily the deeper parts of the tectonic half-grabens. Based on the seismic image analysis, the complex is divided into two series: the lower one, with significantly lower amplitude values and noticeably lower continuity of seismic reflectors and the upper one with diversified dynamics and greater continuity of reflectors. The highest analyzed complex is the carbonate formation of Roetian and Muschelkalk, characterized by high amplitude values and high continuity of reflectors so that it can be easily identified on seismic sections. The analysis carried out with the use of seismic attributes allowed to determine the seismic characteristics of individual lithostratigraphic complexes of the Triassic and Palaeozoic formations and provided more detailed information on the geological structure of the research area.
EN
The Solvay Quarry of Bernburg is one of the most important ichnosites from the Muschelkalk of the Germanic Basin. Extensive surfaces with long chirotheriid trackways have been discovered and assigned to Chirotherium and Isochirotherium. Some undescribed step cycles from this site are analysed here and assigned to Synaptichnium isp. These footprints belong to a “thick-digit” Synaptichnium morphotype recognised at several Middle Triassic sites of Pangaea that seems to differ from the currently valid Synaptichnium ichnospecies. This is the first occurrence of Synaptichnium from this site and the only including step cycles one from the track-bearing Muschelkalk successions of N Germany and the Netherlands. A comparison between the tetrapod ichnoassociations of marginal marine and alluvial units of the Muschelkalk of the Germanic Basin reveals a similar ichnofaunal composition but different relative proportions between ichnotaxa. Rhynchosauroides and Procolophonichnium occur more often in tidal units, whereas the alluvial units show a higher abundance of chirotheriid tracks and an overall greater track diversity.
EN
A sequence- and cyclostratigraphic interpretation of early Anisian (Aegean) shallow-marine carbonate ramp deposits, exposed in outcrop sections west of Tserovo village, NW Bulgaria, is presented. The hierarchical pattern identified can be interpreted in terms of Milankovitch cyclicity with elementary sequences representing the precession (20-kyr) cycle, small-scale sequences the short eccentricity (100-kyr), and medium-scale sequences the long eccentricity (400-kyr) cycle. Palynology provides a robust stratigraphic framework. The study of sedimentary organic matter, revealing variations of terrestrial input, sorting and fragmentation of phytoclasts, and prominent acritarch peaks, allows the interpretation of environmental changes and contributes to the cyclostratigraphic and sequence-stratigraphic framework. The detailed documentation of syndepositional soft-sediment deformation structures confirms their laterally traceable distribution within the depositional sequences and makes them good palaeoenvironmental indicators. Anisian ramp systems of the western Tethyan realm thus were subjected to highly dynamic regimes, recording the interplay between sea-level changes in tune with orbital cycles and ramp morphology.
EN
The Upper Triassic shale of the Qadir Member of the Nayband Formation, East Central Iran has been analysed geochemically to evaluate provenance and palaeogeography. The Qadir Member in the Parvadeh Coal Mine section is 450 metres thick, and includes sandstone, shale, coal, siltstone, and fossiliferous limestone. XRD analysis of shale samples from the Qadir Member largely indicated the presence of illite and chlorite, with small amounts of kaolinite and montmorillonite. On binary and triangular diagrams the data suggests an intermediate igneous source rock for these shales. Plotting the geochemical data on binary diagrams also indicates the tectonic setting of an active continental margin, perhaps reflecting the Early Cimmerian tectonic event with Neothetys subduction under the Iran Plate, and collision of the Iran Plate with Turan during the Late Triassic. The Chemical Index of Alteration (CIA) and Plagioclase Index of Alteration (PIA) values for shale from the Qadir Member of Nayband Formation vary from 74.04 to 80.54 (average 78.02) and 84.31 to 91.85 (average 87.81), respectively, indicating moderate to high chemical alteration in the source area and suggesting a semi-humid climate during deposition. The geochemical data and palaeogeographical models indicate that the Qadir Member shale was deposited on an active margin in a shoreline to transitional-marine setting.
EN
Fossil vertebrate remains from the Keuper unit in the vicinity of the village of Krasiejów have been analyzed for almost two decades. However, the main goal of these works was focused mainly on large vertebrates. Here the authors present the first description of microvertebrate fossils from that site. The collection of around 5,000 specimens is mainly comprised of teeth and scales. The most numerous remains belong to osteichthyans: dipnoans (Ptychoceratodus and cf. Arganodus), palaeoniscids, semionotids, redfieldiids and chondrichthyans, such as Lonchidion sp., which is the first indisputable record of that genus in the Upper Triassic of Poland and the first shark at the Krasiejów locality. Tetrapod fossils consist of temnospondyl amphibians, rhynchocephalian lepidosauromorphs and archosauromorphs. Among them, temnospondyl amphibian remains are the most numerous and are represented mostly by Metoposaurus. However, on the basis of diversity in tooth morphotypes, the occurrence of other taxa cannot be excluded. Rhynchocephalians are composed of 7 fragmentary jaw morphotypes with dentition, which could indicate high taxonomic diversity (cf. Planocephalosaurus, cf. Diphydontosaurus and cf. Clevosaurus). The most varied fossil group was assigned to the archosauromorphs. The authors can distinguish at least 19 teeth morphotypes, which show similarities to the dentition of: protorosaurians (cf. Tanystropheidae), pseudosuchians (cf. Protecovasaurus, cf. Revueltosaurus), early crocodylomorphs and basal sauropodomorph dinosaurs. The first occurrence of a theropod dinosaur and cynodonts at the Krasiejów locality is also recorded. However, their remains are very rare. These new records show a high taxonomic diversity at the Krasiejów locality that contributes to our deeper understanding of Late Triassic ecosystem of Poland.
EN
An excavation dug out in the glacially transported rock masses at Golaszyn near Łuków (eastern Poland), revealed the presence of deposits unknown so far in this area. These are older than the only known so far here glacially transported clays containing concretions with splendidly preserved ammonites of late Callovian at Łapiguz brickyard of Łuków. The succession exposed consists of sands and sandstones of Middle Callovian age which rest on red-brownish clays. The latter may be compared with the Triassic - Buntsandstein deposits of the northwestern Lithuania, that is the home area of glacially transported rock masses, commonly occurring in eastern Poland in the Łuków area. The new geological discoveries markedly increase a set of attractions for the promotion of the Łuków region for the education and geotourism purposes.
EN
This paper presents the results of sedimentological studies of Zechstein marine deposits occurring in the Wleń Graben, a tectonic unit located in the southeastern part of the North Sudetic Synclinorium (NSS; Western Sudetes, SW Poland). Owing to poor exposure, small thickness, and lack of palaeontological data, the stratigraphy and age of these rocks were determined solely on the basis of analogies with adjacent areas. New findings described here, including faunal remains (remains of bivalves, including Liebea sp.), geopetal structures, clastic fills of halite crystals, moulds and bioturbation, shed new light on the environmental interpretations of the Zechstein in this part of the NSS. It should be assumed that at least two types of deposit may be assigned to the marine Zechstein in the Wleń Graben area, namely sparitic and microsparitic dolomite (PZ3) and the overlying deposits of the heterolithic series (PZt). These deposits were formed during the late Zechstein transgression, when the study area was in the marginal southwesternmost part of a newly formed shallow-marine bay of the Polish Zechstein Basin. In the central part of the present-day Wleń Graben, a shallow-marine bay (lagoon?) was dominated by carbonate sedimentation. A north-dipping mud plain, periodically flooded by a shallow sea, occurred in the southern part of the area. The paper summarises the present state of research on Permian deposits in the Wleń Graben, the first comprehensive lithostratigraphic scheme is suggested, and a new concept of the palaeogeographic evolution of the area in the Early and Late Permian is proposed.
EN
The upper Olenekian-Middle Triassic succession of the Tatricum domain (Central Western Carpathians, southern Poland) includes a few horizons of breccias, which are intercalated with early-diagenetic dolostones. On the basis of macroscopic and microscopic (including cathodoluminescence) observations, the paper presents a new interpretation of the genesis of the breccias and their diagenetic history. The rocks studied range from monomictic, cemented mosaic packbreccias to chaotic, unsorted, monomictic, particulate rubble floatbreccias. The processes that preceded the formation of the breccias encompassed the precipitation of evaporites and the early-diagenetic dolomitization of lime muds. The solution-collapse breccias were formed during episodes of cyclic sediment emersions in the upper Olenekian and Middle Triassic, as the result of gradual sediment collapse after karstic dissolution of the intercalated evaporites. After the brecciation process, during diagenesis the rocks were subjected to cementation by sulphate minerals and next, to multi-stage dolomitization. Later tectonic processes led to fracturing and even re-brecciation of the previously formed solution-collapse breccias.
EN
In the Upper Permian continental to marginal-marine succession of the Southern Alps (Dolomites, north Italy), the ichnological record consists of diverse vertebrate footprints and non-diverse invertebrate trace fossils, mainly occurring in the “Bletterbach ichnoassociation” of the Val Gardena Sandstone Formation. After the Permian-Triassic Boundary event, vertebrate ichnoassociations are scarce until the Middle Triassic (Anisian), whereas the uppermost Permian-Lower Triassic Werfen Formation preserves a rich invertebrate trace-fossil record. To date, fish body and trace fossils (Undichna) are very rare in the pre- and post-extinction deposits of the Dolomites; only Undichna gosiutensis Gibert, 2001 was identified in the “Voltago Conglomerate” (Middle Anisian), whereas some unidentified fossil fish casts were found in the Permian Val Gardena Sandstone and some fish remains in the overlying Werfen Formation. Recently, for the first time, fish trails have been discovered in the Val Gardena Sandstone (Lopingian) and in the Werfen Formation (Campil member, Early Triassic, Smithian). Val Gardena Sandstone yielded Undichna cf. quina Trewin, 2000 and U. bina Anderson, 1976 and these represent the oldest fish trails found in the Southern Alps so far. Conversely, the specimens found in the Werfen Formation can be assigned to Undichna cf. britannica Higgs, 1988. They represent the oldest Mesozoic record of fish trace fossils in northern Italy and one of the few records of Undichna from marine environments. These trace fossils are consistent with the fossil association found in the two formations and reflect fish swimming activity in different environments: in very shallow, calm, brackish distal-floodplain to marginal-marine environments in the Late Permian, in association with abundant and diverse tetrapod tracks, and non-diverse invertebrate trace fossils, and in inter- to subtidal calm, shallow, marine environments in the Early Triassic, together with abundant, but not diverse invertebrate trace fossils.
EN
The long-ranging Early to Middle Triassic coniform conodont form-genus Cornudina Hirschmann occurs abundantly in the Anisian of NW Turkey, Northern Tethys. Although suggested to represent the P1 element of an apparatus of the Order Ozarkodinida Dzik, questions concerning the apparatus of Cornudina remain. A description of the probable phylogenetic trends in the P1 elements of Cornudina is attempted and the role of the form-genera Ketinella Gedik and Kamuellerella Gedik, as the alternative ramiform skeletal elements in the Cornudina multi-element apparatus, is investigated. The newly described, Gedikella quadrata gen. nov., sp. nov., is an S element, Kamuellerella rectangularis sp. nov., is either an S3 or an S4 element, and Ketinella goermueshi sp. nov., is an M element.
EN
The uppermost Permian in the NWHoly Cross Mountains is represented by red mudstones with sandstone and conglomerate interbeds, forming the PZt cyclothem (dated by miospores of the Lueckisporites virkkiae Bc Zone), which grade upwards into the Siodta Formation. This succession is overlain by sandstones and mudstones of the Jaworzna Formation yielding the lowermost Triassic spore-pollen assemblage of the Lundbladispora obsoleta- Protohaploxypinus pantii Zone. Mudstones of the Siodta Formation reveal mottling structure with numerous root traces, rhizobreciation, as well as nodular and bedded calcretes. The root -Mader structures are represented by calcite tubules and root moulds, the latter filled with dark red calcareous mudstones. The presence of root traces in the Siodta Formation clearly indicates an increase of substrate moisture in contrast to the underlying PZt cyclothem. The mottled red mudstones were deposited in the playa-lacustrine depositional system and lost their primary structure due to rooting and other pedogenic processes. Carbonate nodules and thin indurated calcretes are related to periods of lower sediment accumulation rate or even non-deposition periods favouring development of continental carbonates. A relatively rapid switch to the alluvial depositional system represented by the Jaworzna Formation appears to be coeval to the increased sediment flux in terrestrial setting, postulated by Newell et al. (2010) at the Permo-Triassic boundary, driven by a devegetation event of upland catchments.
EN
Magnetostratigraphy of the Keuper succession in the southern Mesozoic margin of the Holy Cross Mountains is presented based on investigations of two sections of Brzeziny and Wolica. They cut an ~60 m thick succession of variegated siltstones and claystones, which overlies the Reed Sandstone (Stuttgart Formation). The succession has been correlated with the Patoka Member of the Grabowa Formation, defined in the Upper Silesia region as an equivalent of the Steinmergelkeuper (Arnstadt Formation). The primary Late Triassic magnetization was obtained from component B carried by fine-grained haematite. Twelve magnetic polarity zones, six of normal and six of reversed polarity, have been defined. The obtained polarity pattern corresponds to the Norian (E13–E16 Newark zones) according to the Long-Rhaetian option of the Late Triassic Magnetic Polarity Time Scale. The mean normal polarity characteristic direction (N = 24, D/I = 31/62, k = 28.24, α95 = 6.04) differs significantly from the reversed one (N = 18, D/I = 223/-25, k = 16.38, α95 = 8.65): the primary magnetic signal is partly overlapped by component A carried by magnetite of recent viscuous remanent magnetization. Some samples do contain also coarse-grained haematite that, however, does not form any clustered magnetization. The palaeopole position calculated from the transposed reversed and normal polarity directions of component B corresponds to the Late Triassic (Norian) segment of the reference Baltica/Europe Apparent Polar Wander Path.
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