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EN
The Tsodilo Hills Group strata exposed in the Tsodilo Hills are an association of meta-arenites, metaconglomerates, quartz-mica schists, sandstone, red siltstone and sedimentary breccia deposited on an open siliciclastic marine shelf between the Late Palaeoproterozic and Late Mesoproterozoic, and outcropping in NW Botswana. The succession is dominated by three micaceous quartzite units interlayered with subordinate lenses and wedges of other rock types. Facies gradients from S to N are expressed by: decreasing content of muscovite at all levels of metasediment organisation from thin wedge-shaped units to thick quartzite complexes, as well as a decrease in pebble content and increase in arenaceous matrix in some metaconglomerate beds, matching regional palaeotransport direction. Well-rounded pebbles of extrabasinal rocks are flat, suggesting redeposition from a beach environment. Lenticular conglomeratic bodies with erosional lower boundaries represent infills of local incisions in the sandy bottom sediments. The abundance of laterally discontinuous lithological units reflects shelf palaeotopography controlled and modified by deposition and migration of large bed forms, ranging from megaripple marks (or submarine dunes) to sand waves. Deposition was influenced by tides and two regressive events. The older regression resulted in a marker unit of tidal mudflat-related red-bed facies: mudstone, siltstone, channel-fill sandstone and sedimentary breccia. The second regression is indicated by a tabular conglomerate marker reflecting increased input of coarse terrigenous material.
EN
A 250-m-thick sedimentary succession dominated by siliciclastic deposits occurs in the Kąkolówka Structure of the Skole Nappe. The succession was deposited in the inner part of the Skole Basin during the Late Cretaceous. In position and age, it corresponds to the Kropivnik Fucoid Marl of the Wiar Member (a subdivision of the Ropianka Formation), which was comprehensively described in the external part of the Skole Nappe. In this study, the authors provide the first complete data set on the lithological development and biostratigraphy of the Kropivnik Fucoid Marl from the inner part of the Skole Nappe. The results are compared to previous data from the outer part of the Skole Nappe. In the Kropivnik Fucoid Marl of the Kąkolówka Structure, three main heterolithic facies associations are distinguished: shale-sandstone, marl-sandstone and sandstone-shale. The occurrences of hard, platy and soft marls within siliciclastic rocks are typical of the sections studied. The features observed indicate a turbiditic origin of the deposits studied, including the hard, platy marls. The allogenic material of the strata described includes the small, fragile tests of planktonic foraminifera, which were redeposited from the outer parts of the Skole Basin. Particularly large concentrations of planktonic foraminifera were observed in the hard, platy marls. They are less common in the soft marls and shales. In the Zimny Dział section, a diverse assemblage of benthic and planktonic foraminifera was found. The Kropivnik Fucoid Marl was dated as uppermost Campanian to lowermost Maastrichtian on the basis of planktonic foraminifera, which represent the Gansserina gansseri Zone. The agglutinated foraminiferal assemblages are representative for the lower part of the Rzehakina inclusa Zone and the co-occurrence of the Caudammina gigantea (Geroch) acme with Rzehakina inclusa (Grzybowski) was observed.
EN
The Jurassic through Palaeogene stratigraphy and tectonic structure of the PD-9 borehole at Szczawnica, Pieniny Klippen Belt, West Carpathians, Poland, is revised. The borehole was drilled in the strongly tectonized northern boundary fault zone of the Pieniny Klippen Belt, of Miocene age. Age revision is given by dinoflagellate cysts. Late Cretaceous taxa are reported from the Hałuszowa Formation. The Bryjarka Member (previously with the rank of formation) yielded rich Early Eocene (Ypresian) assemblages. Similar ones are reported from the Szczawnica Formation. A tectonic thrust sheet of the Jurassic Szlachtowa Formation (Grajcarek Unit) in the Palaeogene of the Magura Nappe is evidenced; it yielded late Toarcian-Aalenian dinoflagellate cyst assemblages. The succession of strata recorded from the PD-9 borehole shows the steep, almost vertical attitude of the Grajcarek Main Dislocation at Szczawnica, separating the structures of the Magura Nappe (to the north) and the Pieniny Klippen Belt to the south.
4
Content available Seismo-geological model of the Baltic Basin (Poland)
EN
The aim of this study is to construct a seismo-geological model of the western part of the Baltic Syneclise. This model enables reconstruction of the tectonic processes taking place in this area, which had a significant impact on the formation of prospective zones for the occurrence of unconventional hydrocarbon accumulations. The two seismic surveys Opalino 3D and Kościerzyna-Gdańsk 2D, together with borehole data available in the vicinity, were used for the research. Well data were used not only for the seismic-to-well tie, but also for the construction of well cross-sections (including balanced ones). The structural interpretation of seismic boundaries enabled the separation of four structural stages: Precambrian; Caledonian, Permian-Mesozoic and Cenozoic. The seismic interpretation of the Opalino 3D survey indicates the presence of block-style tectonics in this area. This system is considered to be a part of a large block system, also extending throughout the area of the 2D survey. The Caledonian interval shows the greatest degree of structural complexity. Most of the large Palaeozoic dislocations already had been formed in the Cambrian. They underwent reactivation and/or inversion in the Silurian, or in the final stages of the Caledonian and/or Variscan Orogeny, at the latest. The current shape and structure of the Baltic Syneclise and the development of the Palaeozoic sedimentary cover were significantly influenced by the processes taking place in the Teisseyre-Tornquist Zone (TTZ). The dislocations of the Lower Palaeozoic stage are characterized by general NW-SE and NE-SW trends, although the first of these seems to be dominant.
EN
This paper deals with the lithostratigraphic correlation of the Ordovician-Silurian succession between the Baltic, Podlasie and Lublin basins, located on the SW slope of the East European Craton. The correlation is based on previous lithostratigraphic classifications, which are modified here to include the results of recent biostratigraphic and sedimentological work performed on several new wells. The authors propose to extend the Sasino Formation for the entire upper Darriwilian-lower Katian mudstone sheet that is traceable in all basins. It is recommended that the Jantar Bituminous Claystone Member (late Hirnantian-Aeronian) of the Pasłęk Formation be elevated to the rank of formation and the name Pasłęk Mudstone Formation be retained for the late Aeronian-Telychian, rhythmic alternations of black, laminated mudstones and greenish, bioturbated mudstones. Moreover, the authors suggest that the top of the Kociewie Formation (Sheinwoodian-Ludfordian) be placed at the upper boundary of the Reda Member (latest Ludfordian), which shows much wider lateral persistence than previously was thought.
PL
W artykule przedstawiono możliwości wykorzystania w interpretacji sejsmicznej transformacji PPS-WPG (pionowe profilowanie sejsmiczne – wspólny punkt głębokościowy) obliczonych dla fal podłużnych PP offsetowych punktów wzbudzania. Przedmiotem interpretacji był kompleks utworów dolnego paleozoiku (kambr–sylur) o całkowitej miąższości przekraczającej 2400 m. Pod względem litologicznym kompleks ten zdominowany jest przez utwory silikoklastyczne, z nielicznymi wkładkami skał węglanowych. Do porównania obrazu sejsmicznego uzyskanego na zdjęciu sejsmicznym 3D i transformacjach PPS-WPG dla otworu W-1 – przeprowadzono analizę opartą na wybranych atrybutach sejsmicznych. W ramach artykułu omówiono następujące atrybuty: amplituda średnia kwadratowa, pierwsza pochodna, cosinus fazy, komponent jednakowych częstotliwości, chwilowa szerokość pasmowa, obwiednia, względna impedancja akustyczna. Zastosowanie transformacji pomiarów PPS pozwoliło na uzyskanie zdecydowanie większej rozdzielczości pionowej obrazu, jak również uwidoczniło wyraźne zróżnicowanie litologiczne niektórych formacji. Natomiast interpretacja, przeprowadzona w oparciu o wybrane atrybuty sejsmiczne, umożliwiła szczegółowe rozpoznanie litofacjalne analizowanych utworów dolnego paleozoiku, jak też udokumentowanie sejsmiczne elementów takich jak np. płaszczyzny dyslokacji oraz dodatkowe horyzonty o większej zawartości węglanów.
EN
This article presents the possibilities of using in the seismic interpretation process VSP-CDP transformation (the vertical seismic profiling–common depth point) calculated for longitudinal waves of VSP offset shot points for seismic interpretation. The Lower Palaeozoic (Cambrian-Silurian) complex was a main aim of interpretation. The total thickness of this complex is over 2400 m. The analyzed Lower Palaeozoic complex is dominated by silicoclastic sediments with a few carbonate rock layers. The analysis, based on selected seismic attributes, was performed to compare the seismic image obtained in the 3D seismic and the VSP-CDP transformations for the W-1 well. The article discusses the analysis of following attributes: RMS Amplitude, First derivative, Cosine of phase, Iso-frequency component, Instantaneous bandwidth, Envelope, Relative acoustic impedance. The application of the VSPCDP transformation allowed to obtain much higher vertical resolution of the image, as well as clearly visible lithological variation of some formations. On the other hand, the interpretation, based on selected seismic attributes, enabled a detailed lithofacial recognition of the analyzed Lower Paleozoic deposits as well as seismic documentation of elements such as dislocations and additional new horizons with a higher carbonate content.
EN
The results of lithofacies analysis of clay-marl package (CMP) at Northern Prospect of Petrikov potash deposit are discussed. The analysis has been undertaken to increment waterproof thickness. Lithofacies subdivision has been carried out with ArcGIS 10 software. The following three lithofacies have been defined: sulfate-carbonate-clay, sulfate-clay-carbonate, and clastic-carbonate-clay. An inclusion of gypsum-bearing sub-package of the CMP into the waterproof thickness, based on the lateral lithofacies variation of rocks, will allow pillar mining at the areas, where the mining is prohibited at present by local regulatory documents.
PL
W pracy omówiono wyniki analizy litofacjalnej warstwy ilastomarglistej (WIM) północnej części Pietrykowskiego złoża soli potasowej na Białorusi przeprowadzonej w celu rozpoznania warstw nieprzepuszczalnych. Rejonizację litofacjalną wykonano za pomocą programu ArcGIS 10. Wyróżniono trzy litofacje: siarczanowo-węglanowo-ilastą, siarczanowo-ilasto- -węglanową oraz klastyczno-węglanowo-ilastą. Włączenie do warstwy nieprzepuszczalnej subwarstwy gipsowej WIM, które oparto na lateralnej zmienności litolofacjalnej skał, w przyszłości pozwoli na eksploatację złoża systemem filarowym. Obecnie eksploatacja złoża jest zabroniona.
EN
The thin- and medium-bedded, turbiditic deposits that are exposed in the Bystrica Zone of the Magura Nappe in the Slovak Orava region are the subject of this study. On the basis of lithological features as well as age and stratigraphic position, they are assigned to the Ropianka Formation. The very well exposed rocks of this formation, recognized in the Biela Farma profile in the Slovak part of the northwestern Orava region, are compared with analogous deposits in the Polish Orava and the Beskid Wysoki Mountains. Lithological and biostratigraphical documentation of the Ropianka Formation is presented. This documentation allowed the determination of the age of the rocks studied. Abundant and taxonomically diverse foraminiferal assemblages of agglutinated, benthonic and occasional planktonic forms indicate a Middle Paleocene age for the upper part of the Ropianka Fm. A new stratigraphic position for the Szczawina Sandstone, considered to be a member of the Ropianka Fm, is proposed. The lithostratigraphy of the Ropianka Fm in the Magura Nappe in Poland, Slovakia and the Czech Republic requires further investigation, including the establishment of new type and reference sections. The large outcrop at Biela Farma should be taken into consideration as a potential reference section. Studies of the new sections will lead to a new monographic elaboration of the Ropianka Fm in Poland, Slovakia and the Czech Republic.
EN
The Magura Nappe in the Polish sector of the Outer Carpathians consists of four tectonic subunits characterized by differing development of facies. From the south to the north, they include the Siary, Rača, Bystrica and Krynica subunits. The sedimentary succession in the Rača Subunit in the vicinity of the village of Osielec is composed of Campanian–Palaeogene flysch deposited in the Magura Basin. In this succession, the Middle Eocene Pasierbiec Sandstone Fm consists of thick-bedded sandstones and conglomerates with occasional intercalations of thin-bedded shale-sandstone flysch. Within the Pasierbiec Sandstone Fm at Osielec there is an olistostrome, rich in pebbles and cobbles of exotic rocks. In addition, large blocks of Neoproterozoic metabasites and boulders of Palaeogene organogenic limestones were found. The discovery of metabasites raised the possibility that the rocks in question could be evidence of supposed oceanic crust in the basement of the Magura sedimentary basin, because of the suggestion that they represent the Alpine orogenic cycle. This concept was abandoned when investigations of the absolute age of the metabasites gave a date of ca. 600 Ma. In the Osielec area, there are two tectonic thrust sheets in the Rača Subunit, namely the Osielczyk Thrust Sheet in the north and the Bystra Thrust Sheet in the south; they are folded and cut by a transverse system of strike-slip and oblique faults. The Osielczyk Thrust Sheet was overthrust northwards on to the Siary Subunit.
EN
The upper lower Cenomanian through middle Santonian (Upper Cretaceous) of the Boquillas Formation in the Big Bend Region of Trans-Pecos Texas consists of a marine carbonate succession deposited at the southern end of the Western Interior Seaway. The Boquillas Formation, subdivided into the lower, c. 78 m thick limestone-shale Ernst Member, and the upper, c. 132 m thick limestone/chalk/marl San Vicente Member, was deposited in a shallow shelf open marine environment at the junction between the Western Interior Seaway and the western margins of the Tethys Basin. Biogeographically, the area was closely tied with the southern Western Interior Seaway. The richly fossiliferous upper Turonian, Coniacian and lower Santonian parts of the Boquillas Formation are particularly promising for multistratigraphic studies.
11
Content available Silurian stratigraphy of Central Iran - an update
EN
The Silurian biostratigraphy, lithostratigraphy, and facies of Central Iran including the Kashmar (Boghu Mountains), Tabas (Derenjal Mountains, Ozbak-Kuh), Anarak (Pol-e Khavand) and Kerman regions is reviewed and updated. The current state of knowledge of the Silurian in the Zagros Basin, Alborz, Kopet-Dagh and Talysh regions, as well as in a few areas scattered across the Sabzevar Zone, and the Sanandaj-Sirjan terranes is also reviewed. Silurian volcanism in various parts of Iran is briefly discussed. The end of the Ordovician coincided with a widespread regression across Iran synchronous with the Hirnantian glaciation, and only in the Zagros Basin is there a continuous Ordovician–Silurian transition represented by graptolitic black shales of the Sarchahan Formation. In the Central-East Iranian Platform marine sedimentation re-commenced in the early to mid Aeronian. By the Sheinwoodian, carbonate platform depositional environments were established along its north-eastern margin. In other parts of Iran (e.g., Kopet-Dagh and the Sabzevar Zone), siliciclastic sedimentation continued probably into the late Silurian. The Silurian conodont and brachiopod biostratigraphy of Central Iran is significantly updated facilitating a precise correlation with the Standard Global Chronostratigraphic Scale, as well as with key Silurian sections in other parts of Iran. The Silurian lithostratigraphy is considerably revised and two new lithostratigraphical units, namely the Boghu and Dahaneh-Kalut formations, are introduced.
EN
The Upper Cretaceous of the Elbe Valley in Saxony and the erosion outliers west of it mark an Upper Cretaceous NW-SE-running strait between the Westsudetic Island in the NE and the Mid-European Island to the west. This street connected the NW-German-Polish Basin in the north and the Bohemian Cretaceous Basin (and adjacent regions of the Tethys) in the south. However, post-Cretaceous erosion north of Meißen removed any Upper Cretaceous deposits but erosion outliers at Siebenlehn and especially north of the Forest of Tharandt proof the presence of a marly through silty belt in this area. Three transgressions (base of uppermost Lower to Middle Cenomanian, base of Upper Cenomanian and base of the geslinianum Zone in the mid-Upper Cenomanian) have taken place. The sedimentation was influenced by the topography of the mentioned islands and by movements at structural lines in the Proterozoic and Palaeozoic basement. During the early Late Cenomanian, a marly-silty sedimentation (Mobschatz Formation) in the north existed besides sandy sedimentation in the south (Oberhäslich Formation). The transgression at the base of the geslinianum Zone caused the final submergence of island chains between Meißen, Dresden and Pirna, and a litho- and biofacies bound to cliffs and submarine swells formed. A silty-marly lithofacies, a mixed sandy-silty lithofacies (Dölzschen Formation) and a sandy lithofacies in the south (Sächsisches Elbsandsteingebirge) co-existed during the latest Cenomanian. The first mentioned biofacies yields a rich fauna mainly consisting of oysters, pectinids, rudists, and near-shore gastropods accompanied by echinids and, in some cliffs, teeth of sharks. The Pennrich fauna (Häntzschel 1933; Uhlig 1941) especially consists of the very common serpulids Pyrgopolon (P.) septemsulcata and Glomerula lombricus (formerly Hepteris septemsulcata and G. gordialis).
EN
Prins Karls Foreland (PKF) is a westernmost island of Svalbard Archipelago belonging to the Southwestern Basement Province. The island consists of low-metamorphic facies probably Neoproterozoic metasediments, divided into two, northern and southern parts. Both parts are characterized by similar geological structures but different stratigraphy. New discoveries presented here result from joint, Norwegian Polar Institute and AGH UST Krakow expeditions in 2013 and 2014. Thorough characteristics of the location and character of a strike-slip fault splitting PKF (the Baklia Fault Zone) is presented here for the first time. To date, one succession has been distinguished in the lithostratigraphy of PKF’s basement. The northern part of the island consists of two groups: the Scotiafjellet Group and Grampianfjella Group (Dallmann et al. 2015). They comprise low-metamorphic metasediments (chlorite zone of greenschist facies), mostly slates, metapsamites and carbonates. Stratigraphic units of the southern part represent slightly higher, biotite metamorphic zone, and have been considered to be conformably underlying Scotiafjellet Group. The uppermost Peachflya Group and Geikiebreen Group (mostly phyllites with metavolcanics and carbonates) are in thrust contact with underlying Ferrierpiggen Group, comprising schistose diamictites. The Ferrierpiggen Group is a tectonic unit stratigraphically discontinuous at top and bottom. Isolated klippe of the Ferrierpiggen Group separated from Scotiafjellet Group by tectonic boundary is present in the northern part of PKF (Harland et al. 1979, 1993). These complexes have undergone the Caledonian metamorphism followed by D 1 deformation producing SE directed folding and thrusts. D 2 deformation was coaxial, but not coplanar with D 1. D 2 deformation occurred probably in Mid-Cenozoic and resulted in refolding and thrusting, followed by formation of a dextral shear zone along Scotiadalen (Morris 1989). D 3 deformation is connected with transtensional formation of the Forlandsundet Graben along NNW-SSE faults finishing the West Spitsbergen Orogeny (WSO) (Manby 1986). Distinct difference in the stratigraphy of southern and northern parts of PKF is apparent. The presence of the fault dividing the island was indicated before (Hjelle et al. 1979), but no single fault has been recognized during detailed mapping later on (Harland et al. 1979, Morris 1982, Manby 1986, Morris 1989). Mapping and structural measurements conducted by the authors in the area of Selvågen led to the discovery of the major fault zone (the Baklia Fault Zone – BFZ) dividing PKF into two terrains. The BKF have N-S trend from Haukebukta in the west coast, through the slopes of Alasdairhornet (where it trapped few hundred meters long slab of the Ferrierpiggen Group rocks), to the southern Scotiadalen. Approaching Selvågen, the fault zone bends slightly to the NNE-SSW. The zone is filled with breccias and mixture of different lithologies with slabs of rocks derived from both limbs of the fault zone. The width of the zone measures approximately 100–250 meters. To the east, it is accompanied by at least three narrow subparallel faults. The age of the BFZ is unknown. A brittle character of deformation may suggest that it is Cenozoic in age. En échelon normal faults with a drop to the north, which associate BFZ may be considered as a Riedel shears R 1 formed at the beginning of a strike-slip movement. Structural measurements on slickensides as kinematic indicators revealed that normal faulting was associated with both, dextral and sinistral shear (not simultaneous). A main movement connected with dextral shearing occurred probably earlier, during late stages of the early Cenozoic crustal shortening. The extended width of the fault zone and the presence of a mixture of rock material from both terranes suggest the significant lateral displacement that might reach tens of kilometers. The BFZ cuts through the boundary faults of the Forlandsundet Graben displacing them sinistrally by approximately one kilometer. This suggests that sinistral movement was probably associated with rejuvenation of the fault during late stages or after the Forlandsundet Graben formation. There are several regional implications of BFZ. The stratigraphic relationship of southern and northern terranes is unclear. The presence of BFZ at the boundary of the Scotiafjellet and Peachflya groups does not exclude their stratigraphic succession but makes it impossible to define. The field observations suggest that BFZ may be Cenozoic in age. It has similar tectonic style and orientation to other strike-slip zones present along western Svalbard coast. Strong tectonic deformation suggests displacement of the northern terrain of PKF by tens of kilometers. Even though southern terrain can be directly correlated with Oscar II Land, more research is needed to correlate more exotic northern terrain of PKF with the basement rocks in the southern parts of Spitsbergen. Ongoing research towards dating and detail structural characterization of this regional fault zone will allow for reconstruction of pre-Tertiary position of this part of Archipelago.
EN
The paper presents results of petrographic analyses of glacial tills in the western part of the Kleszczów Graben and the attempt of their stratigraphic interpretation. Petrographic coefficients have allowed the identification of five till lithotypes: T1, T2A, T2 and T2B – assigned to the South Polish Complex (Elsterian) and T4 correlated with the Middle Polish Complex (Saalian). The well-expressed tills that represent the South Polish Complex, occur at the bottom of the section. A new till lithotype, T2B, has been distinguished, corresponding to the Kuców Formation. It supplements the Pleistocene lithostratigraphic section of central Poland and corresponds to the Sanian 2 Glaciation. Among the younger tills, the T4 one (Odranian Glaciation) is well developed. The uppermost tills of the Wartanian cold stage have been reduced by glaciofluvial and fluvial erosion. It is, to some extent a consequence of the existence of a depression in this area, called the Szczerców Basin. The paper highlights the interpretational difficulties concerning the rank and the number of ice sheet advances during the Polish and Middle Polish Complexes in central Poland.
EN
Lithostratigraphic division of the Upper Silesian Keuper continental succession belongs to abandoned matters, even if newly-discovered sites with unique vertebrate faunas highlight an increasing request to more precise designation of their stratigraphic setting. As a result of multidisciplinary grant and with a guide use of new borehole sections, a major lithostratigraphic unit is formally proposed for the middle Keuper (i.e., above the Schilfsandstein; Stuttgart Formation in Stratigraphische Tabelle von Deutschland, 2002), based on previously inaccurately used unit, Grabowa Formation of Bilan (1976). The re-defined Formation of Variegated Mudstones and Carbonates from Grabowa includes Upper Gypsum Beds and Steinmergelkeuper in traditional scheme from Germany (=Weser and Arnstadt Formations), and generally correlates with the Norian stage. Two bone-bearing horizons (Krasiejów and Lisowice) are placed within the unit, which is completely subdivided in three members: Ozimek (mudstone-evaporate), Patoka (marly mudstone-sandstone) and WoŸniki (limestone).
EN
The identification of depositional conditions and stratigraphical position of glacigenic deposits in the Napęków area is important for the genetic and stratigraphical interpretation of Quaternary deposits in the central part of the Holy Cross Mountains, as well as for a revision of the course and extent of Middle Polish (Saalian) glaciations. These deposits comprise a series of diamictons which occur between sandy-gravelly deposits. Based on results of macro- and microscopic sedimentological investigations, analysis of heavy mineral composition, roundness and frosting of quartz grains, as well as OSL dating, this complex must have formed during the Odranian Glaciation (Drenthe, Saalian, MIS 6). Sandy-gravelly deposits are of fluvioglacial and melt-out origin. Diamictons represent subglacial traction till. Their facies diversity is a result of variations in time and space, complex processes of deposition and deformation, responsible for their formation at the base of the active ice sheet. This glacigenic depositional complex was transformed by erosion-denudation and aeolian processes in a periglacial environment during the Vistulian (Weichselian, MIS 5d-2).
EN
The sedimentation of Hieroglyphic beds of the Silesian Nappe took place between the Lower and Middle Eocene and Upper Eocene within the Carpathian Silesian Basin. These beds are represented by thin-bedded flysch containing – at various stratigraphic positions – sandstone-less complexes with variegated shales and bentonite laminae developed in conditions of calm sedimentation with a limited supply of material from the land. The profiles of Hieroglyphic beds of the Silesian Nappe are diversely developed. Their variability and borderline sequences, transitory into overlying and underlying divisions, are presented. In the Ypressian, during the sedimentation of Hieroglyphic beds, foraminiferal associations with numerous small sized Trochammina developed, which formed in the Silesian Basin after the PETM crisis. Since the Lutetian, in slightly more favourable conditions, more differentiated associations have occurred, with Reticulophragmium amplectens (Grzybowski), Ammodiscus (Dolgenia) latus (Grzybowski), and Reticulophragmium gerochi Neagu et al., which preferred cool waters, being index fossils for stratigraphy. Hieroglyphic beds developed during an interval of the gradually cooling climate. The gradual decrease in temperature stimulated the transfer of species: in the Eocene associations of Hieroglyphic beds a number of thermophilous forms, whose optimum of development came in the Upper Cretaceous-Paleocene, disappeared whereas new species appeared which prefer cold waters commonly occurring in boreal basins. The deep restructuring of foraminiferal assemblages took place in the Priabonian, when massive numbers of calcareous benthonic and planktonic forms occurred.
PL
W artykule przedstawiono najnowszą propozycję podziału litostratygraficznego utworów triasu północnej części niecki Nidy nawiązującego do jednostek wyróżnianych na Niżu Polskim oraz w północno-zachodnim obrzeżeniu Gór Świętokrzyskich. Podano charakterystykę petrograficzną skał tworzących zaproponowane wydzielenia. Zamieszczono także wyniki analizy palinofacjalnej utworów triasu. Opisano siedem typów palinofacji odpowiadających różnym środowiskom sedymentacji: rzecznym, jeziornym, playi, sebhy, otwartego morza i laguny. Palinofacje charakterystyczne dla środowiska rzecznego występują w utworach pstrego piaskowca środkowego, piaskowca trzcinowego (formacja stuttgarcka) oraz kajpru górnego, dla środowiska jeziornego – w utworach kajpru dolnego i piaskowca trzcinowego, dla środowiska playi – w dolnych warstwach gipsowych, dla środowiska sebhy – w recie oraz w dolnych i górnych warstwach gipsowych, dla środowiska otwartego morza – w wapieniu muszlowym i dolomicie granicznym, a dla środowiska laguny – w recie, wapieniu muszlowym górnym i dolomicie granicznym. Na podstawie wyników analizy litofacjalnej i palinofacjalnej zrekonstruowano środowisko sedymentacji utworów triasu z północnej części niecki Nidy.
EN
The latest lithostratigraphical scheme of Triassic deposits from the northern part of the Nida Basin (southern Poland) is presented. It refers to the units distinguished in the Polish Lowlands and NW margin of the Holy Cross Mountains. Petrographic characteristics of the proposed lithostratigraphic units, and the results of palynofacies analysis are given. The identified seven palynofacies types represent a variety of depositional environments: fluvial, lacustrine, playa, sebkha, open marine and lagoonal. Palynofacies characteristic for fluvial environments were identified in the Middle Buntsandstein, Schilfsandstein (Stuttgart Formation) and Upper Keuper deposits, lacustrine environment – within the Lower Keuper and Schilfsandstein, playa environment – in the Lower Gipskeuper, sebkha environment – in the Röt as well as Lower and Upper Gipskeuper, open marine environment – within the Muschelkalk and Grenzdolomit and lagoonal environment – in the Röt, Upper Muschelkalk and Grenzdolomit. Depositional environments of the Triassic deposits have been presentedreconstructed based on the lithofacies and palynofacies analyses.
EN
The stratigraphy of the Upper Silesian Keuper, a continental, mudstone-dominated succession is poorly known, although the already renowned, newly discovered vertebrate localities highlight the growing demand for a more precise intra-regional correlation and an appropriate stratigraphic reference framework. A major lithostratigraphic unit, preliminarily proposed for the middle Keuper (i.e., above the Schilfsandstein; Stuttgart Formation in “Stratigraphische Tabelle von Deutschland”, 2002) by Szulc and Racki (2015; Przegląd Geologiczny, 63: 103– 113), is described in detail. The redefined Grabowa Variegated Mudstone-Carbonate Formation, the unit previously based on inaccurately presented information, includes the Upper Gypsum Beds and the Steinmergel-keuper in the traditional scheme from Germany (= Weser and Arnstadt formations). Three members are formally defined: the Ozimek (Mudstone-Evaporite) Member, the Patoka (Marly Mudstone-Sandstone) Member and the Woźniki (Limestone) Member. Two significant bone-bearing horizons (Krasiejów and Lisowice) are placed within the Patoka Mbr. The formation thickness in a composite, regional reference section of the Upper Silesian Keuper, based on the new Woźniki K1 and Patoka 1 well profiles, is approximately 215 m thick. The Grabowa Fm generally correlates with the Norian stage, with the base located in the undefined upper Carnian, and is topped by a major, erosive disconformity and sedimentary sequence boundary, near the Norian-Rhaetian boundary. However, hiatuses in the Silesian middle Keuper succession are located and paired with a cannibalistic type of sand-mud flat deposition, largely controlled by Early Cimmerian movements of tectonic blocks associated with the Kraków–Lubliniec shear zone.
EN
At least three widely separated bone-bearing intervals in the Upper Triassic succession of Upper Silesia, ranging in age from the Carnian to Rhaetian (i.e., in the interval of 25 Ma), are presented in papers by the Warsaw research group, led mainly by Jerzy Dzik and/or Grzegorz Niedźwiedzki. The stratigraphic arguments are reviewed for the vertebrate localities studied so far, in particular for the well-known middle Keuper sites at Krasiejów and Lipie Śląskie, to show that the previously proposed age assignments are still inadequately documented and questionable. This unreliability is exemplified by the evolving stratigraphic correlation of the fragmentary Silesian sections (8–18 m thick) with informal subsurface units from central-western Poland and with the German standard succession, ultimately not corroborated by comparison with the composite reference succession of the Upper Silesian Keuper, including new profiles (ca. 260 m thick) from the Woźniki K1 and Patoka 1 wells. Based on a multidisciplinary stratigraphic study covering consistent litho-, bio-, climato- and chemostratigraphic premises, focused on the regional reference section, two bone-bed levels only are recognized in the Patoka Marly Mudstone-Sandstone Member (= Steinmergelkeuper) of the Grabowa Formation, not very different in age (Classopollis meyeriana Palynozone; probably IVb Subzone): (1) the localized Krasiejów bone breccia level (early Norian in age) in the Opole region, and (2) the far more widely distributed Lisowice bone-bearing level (middle Norian) in a vast alluvial plain (braided to anastomosing river system) during the Eo-Cimmerian tectonic-pluvial episode. As a consequence of the principal uncertainties and controversies in Upper Triassic terrestrial stratigraphy, this is still a somewhat preliminary inference. Typical skeletal concentra- tions of a combined hydraulic/sedimentologic type, related to fluvial processes, are common in the Upper Silesian Fossil-Lagerstätten, although factors governing preservation are probably important, as well.
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