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EN
The classical locality of Svinary in the eastern Bohemian Cretaceous Basin is the site of new biostratigraphic investigations. Besides some scarce macrofossil evidence, bulk sedl ment samples were processed to retrieve micropalaeontological assemblages, and calcareous nannofossil smearslides were analysed. The studied material provided calcareous nannofossil assemblages including Micula staurophora, Lithastrinus septenarius and Broinsonia parca expansa, thus documenting the Middle Coniacian (upper part of UC10 Zone and lower part of UC11 Zone). The foraminifera assemblage is relatively rich, planktonic species show a wide stratigraphical range, while the benthic association represented by Neoflabellina suturalis suturalis and Gaudryina carinata is very similar to the Coniacian biozone of Stensioeina granulata-Eponides whitei, valid for the Bohemian Cretaceous Basin. Ostracods are represented by two common cytherellid species, and two rare ornamented species: Imhotepia marssoni? and Pterygocythereis spinosa. Inoceramid bivalves, namely Platyceramus mantelli, and a newly recorded ammonite, Tridenticeras tridens, support the late Middle Coniacian age of the Svinary outcrop. New biostratigraphic results are given along with palaeoecological interpretations of newly collected fossil material.
EN
In the Paratethys Sea, isolation, the development of anoxia and stratification of the water column resulted in deposition of organic-rich sediments. In the Western Carpathians (Central Paratethys) these sediments now lie within the Menilite Formation. Whereas the Eocene-Oligocene transition has been studI ed in the Western Carpathians and is documented by dinoflagellate cyst assemblages, the dinoflagellate cyst stratigraphy of the Menilite Formation members has been uncertain. The Popiele Member and the Menilite Formati on exposed at Aksmanice (Boryslav-Pokuttya Nappe, Western Outer Carpathians) reflect palaeogeographic changes at the beginning of the Oligocene. These previously studied deposits have been assigned to lithostratigraphic units, though without biostratigraphic documentation. The age of the Menilite Fm. in the Carpathian sedimentary succession is particularly interesting dueto the diachronous character of the facies development. In this study we provide biostratigraphic data based on well-preserved organic-walled dinoflagellate cyst assemblages. The marker taxa recovered indicate a Rupelian age (Early Oligocene) for the Menilite Fm. A different assemblage occurs in the Popiele Member underlying the Menilite Fm. Here, the dinoflagellate cysts are more diverse and abundant, and represented by typical Eocene taxa attributed to Areosphaeridium spp. and Charlesdowniea spp. The Popiele Member may be assigned to the Priabonian (Late Eocene).
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.
EN
This paper deals with the graptolite biostratigraphy and age determination of the Ordovician and Silurian lithological successions of the Baltic, Podlasie and Lublin basins that existed during the early Palaeozoic on the SW slope of the East European Craton. The biostratigraphic research described was conducted on core material coming from old boreholes and cores from several new wells. Graptolite zones were identified and the chronostratigraphic succession was constrained, with the depths to the stratigraphic units, especially those considered prospective for petroleum, being determined in the individual borehole sections. Old local stratigraphic schemes of the Silurian used for many years in the Polish geological literature are correlated with the standard schemes. The most complete succession of graptolite zones, both in the Ordovician and the Silurian, is observed in the Baltic region. The number of stratigraphic gaps increases towards the east and southeast of the regions. The stratigraphic range of the Sasino Shale Formation decreases in this direction; in the Podlasie and Lublin regions, it comprises only the Katian Stage. The stratigraphic range of the Jantar Formation in the western part of the area spans not only the Rhuddanian but also part or the whole of the Aeronian. In the Podlasie and especially the Lublin regions, sedimentation of the Jantar Formation began in the latest Rhuddanian–Aeronian. A large stratigraphic gap, spanning part or the whole of the Llandovery and increasing eastwards, was documented in the Podlasie-Lublin region. The biostratigraphic research allowed a more precise constraint on the temporal and spatial extent of erosion of Pridoli deposits and the beginning of coarse-grained, siliciclastic sedimentation (Kociewie Formation) in the Baltic Basin.
EN
The succession of bioevents in planktonic foraminifer and calcareous nannoplankton communities is reviewed and summarized for the Carpathian Foredeep and northern Pannonian Basin in the time interval between ~16 and 13.5 Ma. This succession can be subdivided into three principal intervals: (1) an interval with rare Praeorbulina sicana and P. glomerosa. It was characterized by a limited immigration of index taxa linked to the lack of a warm surface water layer in the Central Paratethys. This interval can be correlated with the first Badenian transgression near the Burdigalian/Langhian boundary. The rare occurrence of biostratigraphical markers does not allow its precise dating and interregional correlation; (2) a brief interval of the first occurrences of Praeorbulina circularis, Orbulina suturalis and Helicosphaera waltrans. This can be related to the formation of a warm surface water layer suitable for the survival of orbulinas and praeorbulinas and a change from estuarine to anti-estuarine circulation. This interval can be correlated with the second Badenian transgression, which, however, was not isochronous over the area as inferred from different successions of these first occurrences; (3) a limited appearance of new index taxa in the Central Paratethys prior to the Wielician Salinity Crisis. This time interval was characterized by increased seasonality and salinity oscillations followed by climate cooling. A “reverse” migration of the stress-tolerant species Helicosphaera walbersdorfensis from the Central Paratethys to the Mediterranean is suggested. Several local bioevents with limited stratigraphic correlation potential have been recognized in this interval.
EN
The early Badenian interval in the Central Paratethys realm is characterized by a major marine transgression into the Pannonian and Carpathian Foredeep basins. In the western part of the Polish Carpathian Foredeep, Badenian sedimentation started generally with conglomerates (Dębowiec Formation) passing into a thick succession of claystones and mudstones with rare sandstone interbeds (Skawina Formation). Profiles containing a full sequence of lower Badenian strata are relatively rare, and are mainly known from boreholes. In this paper, we present new results on samples taken from such a borehole (Kaczyce K2/07) located near the town of Cieszyn. We focus on reconstructing the chronology of the lower Badenian marine sediments at the beginning of the transgression in the Carpathian Foredeep (lower Skawina Fm.) using radio-isotopic dating (40Ar/39Ar) of a volcanoclastic layer (tuff and tuffite) and biostratigraphy of calcareous nannoplankton and foraminifera.The weighted mean 40Ar/39Ar age for sanidine separates from the tuff provided an age of 14.27 ± 0.03 Ma. This age is consistent with the NN5 and MNN5a nannofossil zones determined in this study. Our foraminiferal assemblages show that the basal beds of the Skawina Formation up to the tuffites correspond to the Orbulina suturalis–Praeorbulina glomerosa Zone (according to Cicha et al., 1975) and cover the interval of the Lower Lagenidae Zone–lowermost Upper Lagenidae Zone (Grill, 1941). The petrographic data from the tuffite allow correlation of the tuffite from the Kaczyce K2/07 borehole to the level of the Chełmek Tuffite Bed (Alexandrowicz, 1997) providing a regional correlation horizon for future studies.
EN
The foraminifera-based biostratigraphy of the Middle and Upper Jurassic of the Polish Lowlands was re-evaluated. Biostratigraphic charts providing ranges of the most important foraminiferal taxa characteristic of individual Jurassic stages are presented in relation to the currently used ammonite-based standard stratigraphic divisions. The study contains the new research on the foraminifera fauna and includes earlier results available in published and archival reports. In the Oxfordian and Lower Kimmeridgian deposits, various foraminiferal assemblages were distinguished with reference to the lithofacies in the individual parts of the Polish Basin and varying influences of the palaeogeographical provinces. Additionally, the foraminiferal zones in the Oxfordian and Lower Kimmeridgian deposits of southeastern Poland are distinguished based on detail study of foraminifers.
EN
Early Palaeocene through early Eocene silicoflagellate assemblages were examined from five southern subtropical through subpolar deep-sea sites: DSDP Holes 208 and 524, and ODP Holes 700B, 752A, and 1121B. For each site, the taxonomic composition of the silicoflagellate assemblage is documented in detail; Pseudonaviculopsis gen. nov., Dictyocha castellum sp. nov. and Stephanocha? fulbrightii sp. nov. are proposed, along with several new combinations. More importantly, however, these observations enable a considerable refinement to the existing Palaeocene–Eocene silicoflagellate biostratigraphic zonation that for the first time uses datums calibrated to the Geomagnetic Polarity Timescale. The Corbisema aspera Interval Zone occurs immediately above the K/Pg boundary and is here described from Seymour Island. The Corbisema hastata Partial Range Zone extends from near the K/Pg boundary to late early Palaeocene and has been observed in Hole 208. The Pseudonaviculopsis disymmetrica Acme Zone occurs in Holes 208 and 700B. The Dictyocha precarentis Partial Range Zone, observed in Holes 208, 700B, 752A and 1121B, is subdivided into D. precarentis, Naviculopsis primativa, N. cruciata and Pseudonaviculopsis constricta subzones. The Naviculopsis constricta Partial Range Zone occurs in Holes 524, 700B, 752A and 1121B. This study is also the first to consider syn- and/or diachroneity in Palaeogene silicoflagellate biostratigraphy.
EN
The radiolarian biostratigraphy of the Middle–Upper Jurassic pelagic siliceous sediments (Czajakowa Radiolarite Formation) in the Niedzica succession of the Pieniny Klippen Belt (Carpathians) is interpreted in terms of their age in a stratotype section, and facies equivalents in other tectonic-facies units of this region. The siliceous sediments are represented by radiolarian cherts and silicified limestones which are underlain and overlain by red nodular limestones, equivalents of the Rosso Ammonitico facies. The radiolarian association includes thirty-seven taxa belonging to twenty one genera which represent the Northern Tethyan Palaeogeographic Province. Key radiolarians recorded provide a means of correlation with zonation schemes based on Unitary Associations defined for the Jurassic Tethyan sediments. The age of the Czajakowa Radiolarite Formation in the stratotype section is determined as U.A.Z.9 to U.A.Z.11 corresponding to middle Oxfordian up to Kimmeridgian. Comparison of radiolarian biozones from the stratotype section with other facial equivalent sections in the Pieniny Klippen Belt reveals a significant diachronism for both the lower and the upper limits of the Jurassic pelagic siliceous facies.
EN
Sparse fish microremains have been found in marine limestones from the Middle Devonian (Givetian) Skały Formation (Sitka Coral-Crinoid Limestone Member and Sierżawy Member), Świętomarz–Śniadka section, Bodzentyn Syncline, Łysogóry Region, northern Holy Cross Mountains, associated with conodonts of the hemiansatus to ansatus zones. Thelodont scales referred here to Australolepis sp. cf. A. seddoni come from near Śniadka village, from samples dated as hemiansatus to rhenanus/varcus zones. This increases the known range for the genus from its original find in Western Australia. The presence of a thelodont in the late Middle Devonian in Poland extends the known distribution of turiniids around the peri-Gondwana shorelines of Palaeotethys.
EN
The lower (but not lowermost) part of the Upper Cretaceous Anaipadi Formation of the Trichinopoly Group in the area between Kulatur, Saradamangalam and Anaipadi, in the south-western part of the Cauvery Basin in southeast India yielded rich inoceramid and ammonite faunas. The ammonites: Mesopuzosia gaudama (Forbes, 1846), Damesites sugata (Forbes, 1846), Onitschoceras sp., Kossmaticeras (Kossmaticeras) theobald ianum (Stoliczka, 1865), Lewesiceras jimboi (Kossmat, 1898), Placenticeras kaffrarium Etheridge, 1904, and Pseudoxybeloceras (Schlueterella) sp., are characteristic of the Kossmaticeras theobaldianum Zone. The absence of Peroniceras (P.) dravidicum (Kossmat, 1895) indicates the presence of only lower part of this zone, referred to the nominative Kossmaticeras theobaldianum Subzone at the localities studied. The inoceramids present are Tethyoceramus madagascariensis (Heinz, 1933) and Cremnoceramus deformis erectus (Meek, 1877), recorded for the first time from the region. The latter dates the studied interval as early early Coniacian, and allows, for the first time, direct chronostratigraphic dating of the Tethyoceramus madagascariensis Zone, and consequently also of the Kossmaticeras theobaldianum Subzone. As inoceramids occur in the middle part of the ammonite-rich interval, the Kossmaticeras theobaldianum Subzone may be as old as latest Turonian and not younger than early early Coniacian. The base of the Coniacian lies in the lower, but not lowermost part of the Anaipadi Formation. Both inoceramids and ammonites represent taxa known from Madagascar and South Africa.
EN
Triceratium barbadense Greville, 1861a, T. brachiatum Brightwell, 1856, T. inconspicuum Greville, 1861b and T. kanayae Fenner, 1984a, are among the most common diatoms reported worldwide from lower to middle Eocene biosiliceous sediments. Due to complicated nomenclatural histories, however, they are often confused. A morphometric analysis performed herein indicates that T. brachiatum is conspecific with T. inconspicuum, and that both were previously often misidentified as T. barbadense. Triceratium barbadense sensu stricto is a distinct species similar to Triceratium castellatum West, 1860. Triceratium brachiatum and T. kanayae are transferred herein to a new genus, Fenneria, for which a close phylogenetic relationship with Medlinia Sims, 1998 is proposed. A review of the geographic and stratigraphic distribution of Fenneria shows that the best constrained records of its occurrences are found at DSDP Site 338, and ODP Sites 1051 and 1260. The ages of the base (B) and top (T) of each species’ stratigraphic range are calibrated here to the Geomagnetic Polarity Timescale either directly or inferred via correlation with dinocyst biostratigraphy. Latitudinal diachroneity of ~7 million years is documented for F. brachiata, which disappears earlier in tropical and mid-latitude sites than in the northern high latitudes. These observations, coupled with a preliminary compilation of the Chron C20n taxonomic composition of pelagic diatom assemblages for Sites 338, 1051 and 1260, indicate that diatoms diversified palaeobiogeographically considerably earlier than the Eocene-Oligocene Transition, as commonly believed. This study also emphasizes the importance of the detailed examination of specimens from both museum collections and deep-sea cores as a step toward enhancing the utility of Palaeogene diatoms in palaeoceanographic and palaeoenvironmental reconstructions.
EN
The Silurian fishes from north-western Hunan, China are characterised by the earliest known galeaspids Dayongaspis Pan and Zeng, 1985 and Konoceraspis Pan, 1992, and the earliest known antiarch Shimenolepis Wang J.-Q., 1991, as well as rich sinacanth fin spines. Shimenolepis from Lixian County in north-western Hunan, which was dated as the Telychian (late Llandovery), has long been regarded as the oldest representative of the placoderms in the world. As such, in addition to eastern Yunnan and the Lower Yangtze Region, north-western Hunan represents another important area in South China that yields important fossil material for the research of early vertebrates and related stratigraphy. Here we summarise the Silurian fishes known in north-western Hunan so far, and classify them into three vertebrate assemblages (i.e., the Wentang, Maoshan, and Yangtze assemblages). Based on the updated Silurian vertebrate and stratigraphic databases, the Silurian fish-bearing strata in north-western Hunan can be subdivided into the Rongxi, Huixingshao, and Xiaoxi formations in ascending chronological order, which can be correlated with the Lower Red Beds, the Upper Red Beds, and the Ludlow Red Beds in South China, respectively. A new look at the Silurian strata in Lixian suggests that the age of Shimenolepis is late Ludlow rather than late Llandovery as previously suggested. The research on Silurian fishes and biostratigraphy in north-western Hunan not only provides morphological data of early vertebrates, but also offers new palaeoichthyological evidence for the subdivision, correlation, and age assignment of the Silurian marine red beds in South China. The establishment of a related high-precision Silurian stratigraphic framework in north-western Hunan will help to elucidate the temporal and spatial distribution of Silurian fossil fishes, deepen the understanding of the evolution of early vertebrates, and unravel the coevolution between Silurian vertebrates and the palaeoenvironment.
EN
The new monotypic ammonite genus Xenosphinctes (type species: Xenosphinctes berkai n. sp.) is established. It is recorded from the Upper Jurassic, Early Tithonian, Hybonotum Zone, Riedense Subzone, eigeltingense α horizon from the Talmühle, N of Engen, Baden-Württemberg, SW Germany.
EN
The Early Kimmeridgian of the Wieluń Upland and adjoining regions, after the decline of sedimentation of the deep-neritic sponge megafacies (Częstochowa Sponge Limestone Fm.) and associated limestones and marls with poor benthic fauna (Pilica Fm.) during the Planula Chron, showed the subsequent development of moderately shallow-water biostromal chalky limestones with siliceous sponges and corals, replaced laterally by micritic limestones and marls (Prusicko Fm.) during the Platynota Chron and the earliest Hypse¬locyclum Chron. Towards the north and south shallow-marine carbonate platforms occurred (represented by deposits of the “oolitic” fm.), whereas towards the north-west and west deeper marine facies, represented initially by limestones with siliceous sponges (Częstochowa Sponge Limestone Fm.), and later during the Hypselocyclum Chron by bedded limestones and marls with ammonites (Burzenin Fm.) were deposited. This palaeogeographic pattern was controlled by the synsedimentary tectonics. The detailed biostratigraphical classification of the deposits studied from the Platynota to the Divisum zones, and their lithological character, enable the recognition of the primary sedimentary cyclicity by comparison with the well dated short eccentricity cycles in the coeval succession of south-eastern France. The two appendixes enclosed give the characteristics of: (1) the characteristics of the ammonite faunas especially of the families Ataxiocerati¬dae and Aulacostephanidae (where two new species are established – Balticeras samsonowiczi sp. nov., and Rasenioides glazeki sp. nov.); (2) the newly established lithostratigraphical units: the Prusicko Fm., and the Burzenin Fm., and the smaller rank units (members, beds) recognized therein.
EN
Two new species of ostracods of the family Progonocytheridae Sylvester-Bradley Camptocythere (C.) lateres Tesakova et Shurupova, sp. nov. and C. (C.) angustius Tesakova et Shurupova, sp. nov. from the Michalskii and Besnosovi ammonite zones (Upper Bajocian – Lower Bathonian, Middle Jurassic) of the Sokur section (Saratov) are described. The changes in ontogenesis in the phylogeny of Camptocythere (C.) lateres Tesakova et Shurupova in the stratigraphical interval corresponding to the Palaeocytheridea kalandadzei ostracod Zone, and especially to the beds with C. (C.) lateres, have been studied. The levels of the change in the predominant type of sculpture (corresponding to evolutionary boundaries) are recognized in the sculpture development among the adult representatives of the species in its phylogeny. This palaeobiogenetic (heterochrony) approach allows subdivision of the beds with C. (C.) lateres into three stratigrapical intervals characterized by changes in the type of sculpture.
EN
The southern slope of Łysica Mountain, which is the highest elevation of the Holy Cross Mountains, is comprised of three lithological complexes divided by parallel fault zones. The uppermost part of the succession consists of quartzitic sandstone of the Wiśniówka Formation. The formation is underlain by a complex of sandstone with mudstone interbeds, with black claystone underneath, which is exposed in the upper part of the Glęboczka ravine succession. The strata of the first and the third complexes dip northward, whereas those of the second complex dip southward. In the fault-bound zone between the second and the third complexes, there are concentrations of weathering iron ore. The black claystone, which is lithologically similar to this of the Pepper Mountains Formation, contains a taxonomically rich assemblage of organic-walled microfossils (acritarchs) diagnostic of the Upper Cambrian (Lower Furongian) successions. The new record of microfossils allows determining the age of the succession composing the Łysogóry Mountains for the first time in the history of regional geological investigation.
EN
Two sections of strata assigned to the Amran Group at Jabal Salab and Jabal Yam in the eastern Sana’a governorate were sampled and correlated. These sections are part of a carbonate platform that extends from the city of Marib in the east to Naqil Ibn Ghailan, 20 km east of the city of Sana’a to the west. Palaeontological analysis of samples recovered has resulted in identification of 123 foraminiferal species, which are used to subdivide the sequence of the Amran Group into five biostratigraphic zones, aged between Bathonian (Middle Jurassic) and Berriasian (Early Cretaceous). The proposed biozones are those of Riyadhella rotundata, Kurnubia jurassica, Ammomarginulina sinaica, Alveosepta jaccardiand Pseudocyclammina sulaiyana/Furitilla caspianseis. These biozones were constructed and correlated with the equivalent zones reported from several localities.
EN
Upper Campanian–Maastrichtian sections on the western flank of the Hun Graben in the Western Sirte Basin (WSB) are displaying two major type facies based on the foraminiferal assemblages. The first one indicates open-marine to outer-shelf conditions, and is represented by numerous bathy-pelagic planktonic foraminiferal species referable to the Radotruncana calcarata, Globotruncana aegyptiaca and the lower part of the Gansserina gansseri Zone (all late Campanian).The second type facies indicates an inner-shelf environment and is represented in the middle-upper part of the Gansserina gansseri Zone (early Maastrichtian) and Racemiguembelina fructicosa (late Maastrichtian) dominated by epi-pelagic planktonic and large benthic foraminifers. Large benthic foraminiferal index species Siderolites calcitrapoides Lamarck and Omphalocyclus macroporus (Lamarck) occur in abundance by the middle–late Maastrichtian. Correlation between planktonic foraminiferal zonation and large benthic foraminiferal zonation is given. An open-marine to outer-shelf environment passed into shallower marine conditions during the late Campanian–early Maastrichtian to late Maastrichtian, then a slight deepening and again shallowing is noticed.
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