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    Tytuł:
    The middle/late Eocene transition in the Eastern Carpathians (Romania) based on foraminifera and calcareous nannofossil assemblages
    Autorzy:
    Bindiu, R.
    Filipescu, S.
    Balc, R.
    Cocis, L.
    Gligor, D.
    Powiązania:
    https://bibliotekanauki.pl/articles/2060159.pdf
    Data publikacji:
    2016
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    microfossils
    biostratigraphy
    paleoecology
    turbidites
    Tarcău Nappe
    Opis:
    Foraminiferal and calcareous nannofossil assemblages from the Eastern Carpathians (northern part of the Tarcău Nappe, Romania) were documented and correlated in order to reconstruct the palaeonvironmental settings and provide a biostratigraphic framework of the Plopu Formation. The benthic foraminiferal assemblages are dominated by flysch-type agglutinated taxa, suggesting a bathyal palaeodepth with frequent oscillations of the carbon compensation depth. The agglutinated foraminifera morphogroup analyses suggest different levels of organic matter influx and oxygenation. Both the foraminifera and calcareous nannofossil assemblages suggest a shift between the warm mid Eocene to the cooler late Eocene climate. Biostratigraphic data based on calcareous nannofossils (NP15–NP19/NNTe8–NNTe12 biozones) helped to establish the age of the formation. Four assemblages of benthic agglutinated foraminifera (Psammosiphonella cylindrica – Nothia excelsa; Paratrochamminoides spp. – Trochamminoides spp.; Karrerulina spp.– Reticulophragmium amplectens; Spiroplectammina spectabilis) correlated with calcareous nannofossil bioevents supported the placement of the mid to late Eocene transition within the Plopu Formation.
    Źródło:
    Geological Quarterly; 2016, 60, 1; 38--55
    1641-7291
    Pojawia się w:
    Geological Quarterly
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Deep-sea trace fossils from the Numidian Formation (Upper Oligocene–Lower Miocene) in the Ouarsenis Mountains, northwestern Algeria
    Autorzy:
    Menzoul, Bouabdellah
    Uchman, Alfred
    Adaci, Mohamed
    Bensalah, Mustapha
    Powiązania:
    https://bibliotekanauki.pl/articles/2135034.pdf
    Data publikacji:
    2022
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    ichnology
    flysch
    turbidites
    Atlas
    Paleogene
    Neogene
    Opis:
    Trace fossils and lithofacies have been studied for the first time in the Numidian Formation (Upper Oligocene–Lower Miocene) of the Ouarsenis Mountains in Algeria to interpret their depositional environment. Twenty-two ichnogenera have been recognized in eight lithofacies of three main facies associations in four representative sections. Distribution of the trace fossils is dependent on the facies. Most trace fossils are dominated by post-depositional forms (62%) and occur in fine-grained, thin-bedded sandstones of facies F4. They belong to the Ophiomorpha rudis, Paleodictyon and the Nereites ichnosubfacies of the Nereites ichnofacies. The O. rudis ichnosubfacies is recorded in 1) medium- to very thick-bedded sandstones of the facies association FA1, interbedded with thinner sandstone beds of the facies F2 and F4 in the upper unit of the sections studied, which were deposited in channel fill and levee-overbank environments, and in 2) medium- to thin-bedded sandstones of the facies association FA2 in the lower unit of the Kef Maiz and the Ain Ghanem sections, which were deposited in isolated narrow channels within the mud-dominated part of the depositional system and occasionally fed with turbiditic sand. The Paleodictyon ichnosubfacies occurs in thin- to medium-bedded sandstones (FA2) of the lower units in the Ain Ghanem and Kef Maiz sections and the lowest part of the upper unit of the Kef Maiz section, which were deposited in channel margin or foremost channel-to-levee-overbank areas. The Nereites ichnosubfacies is recorded in thin-bedded sandstones (FA2), which were deposited in crevasse-splays or small lobes on a basin floor invaded occasionally by turbidites against a background of pelagic and hemipelagic sedimentation.
    Źródło:
    Geological Quarterly; 2022, 66, 2; art. no. 1
    1641-7291
    Pojawia się w:
    Geological Quarterly
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Geotectonic significance of Carboniferous deposits NW of the Holy Cross Mts. (central Poland)
    Autorzy:
    Jaworowski, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/2059900.pdf
    Data publikacji:
    2002
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    Central Poland
    Carboniferous
    debrites
    turbidites
    flysch
    pseudoflysch
    Opis:
    Carboniferous sandstones and shales encountered in deep boreholes drilled in central Poland, NW of the Holy Cross Mts., represent a pseudoflysch i.e. they show facies features of flysch and, simultaneously, are of cratonic provenance. Clastic sediments were derived from a peripheral bulge formed within the East European Craton as a result of stresses exerted by the accretion/thrust wedge advancing up the marginal part of the craton. In central Poland, NW of the Holy Cross Mts., a Variscan foredeep existed. The foredeep was the depositional site of interfingering exo- and pseudoflysch which, from a geodynamic point of view, are equivalent to an outer molasse. Huge masses of Carboniferous deposits (generally corresponding to flysch) from southwestern and central Poland successively represent, moving from SW to NE, Variscan ortho-, exo- and pseudoflysch.
    Źródło:
    Geological Quarterly; 2002, 46, 3; 267-280
    1641-7291
    Pojawia się w:
    Geological Quarterly
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Trace fossils from Silurian and Devonian turbidites of the Chauvay area, southern Tien Shan, Kyrgyzstan
    Autorzy:
    Warchoł, M.
    Leszczyński, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/191469.pdf
    Data publikacji:
    2009
    Wydawca:
    Polskie Towarzystwo Geologiczne
    Tematy:
    Tien Shan
    Kyrgyzstan
    Silurian-Devonian
    turbidites
    trace fossils
    Opis:
    The siliciclastic turbidite successions (Pul’gon and Dzhidala Formations) that crop out in the eastern part of the Chauvay River valley, are marked on geological maps as a belt of terrigenous deposits of Silurian–Devonian age. They resemble deposits of overbank areas and depositional lobes of deep sea fans, and display common trace fossils particularly on lower surfaces of sandstone beds. Sixteen ichnotaxa representing four morphological groups have been distinguished. The trace fossil assemblages suggest their affiliation to the Nereites ichnofacies. Various branched, preturbidite forms predominate in both examined units, although the assemblages of individual units differ slightly in composition. In the Pulg’on Formation, small, densely distributed burrows commonly occur on lower surfaces of sandstone beds. Shallow burrowing depth together with relatively low diversity trace fossil assemblages indicate lowered oxygenation of the sea floor.
    Źródło:
    Annales Societatis Geologorum Poloniae; 2009, 79, No 2; 1-11
    0208-9068
    Pojawia się w:
    Annales Societatis Geologorum Poloniae
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Age, internal stratigraphic architecture and structural style of the Oligocene–Miocene Numidian Formation of northern Tunisia
    Autorzy:
    Riahi, S.
    Soussi, M.
    Ben-Ismail-Lattrache, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/191220.pdf
    Data publikacji:
    2015
    Wydawca:
    Polskie Towarzystwo Geologiczne
    Tematy:
    Numidian Formation
    stratigraphy
    Oligocene
    Miocene
    turbidites
    structural analyses
    Opis:
    The stratigraphy of the Numidian Formation of northern Tunisia and its internal organization are updated. Planktonic foraminifera point to a mainly Oligocene–Early Miocene age of this formation in the majority of the sections studied. Some key lithological horizons are recognized within the early Miocene succession, allowing lateral correlation between the outcrops of the Mogod and Kroumirie mountains. These include: (1) a conglomeratic interval, up to 1–2 m thick and rich in reworked glauconitic boulders, limestone fragments of the Tellian (Eocene) and pectinid bivalves; and (2) a relatively continuous glauconitic level. In the new stratigraphic scheme, the Zouza, Ben Metir and Sejnene sections represent the entire Numidian Formation. A lower unit (200–700 m thick), highly pelitic with subordinate sandstone beds was distinguished, overlain by an upper unit which is sandier, especially in its uppermost part (1,000–1,500 m thick). In the present study, these have been stratigraphically dated as Oligocene–Early Miocene p.p. (Rupelian–Chattian; P19–P21 zones) to Aquitanian (N4 Zone) and Miocene (Aquitanian–early Burdigalian; N4–N5 zones), respectively. In the areas studied, the sandy succession assigned to the Kroumirie Member begins with a sandstone unit with an erosional base or a major discontinuity, locally marked by conglomerates made up of various reworked components. It rests generally on a thick shale unit that characterises the upper part of the Zouza Member. The thinner, uppermost succession of the Numidian Formation represents the Babouch Member, dated as Burdigalian (N6–N7 zones). Within the framework of the new proposal, the total stratigraphic thickness of the Numidian Formation in northern Tunisia does not exceed 2,200–2,600 m. Internally, the Numidian Formation is transected by the Intra-Numidian Thrust and back-thrust faults, associated with faulted folds that are recognized in outcrop on different scales and in seismic sections. Along these thrust and/or reverse faults, the middle to upper Eocene deposits have undergone uplift and are exposed at the surface (e.g., Dowar Larmel in Meloula-Tabarka, Gaâret Sejnene and Sidi M’chreg sections).
    Źródło:
    Annales Societatis Geologorum Poloniae; 2015, 85, 2; 345-370
    0208-9068
    Pojawia się w:
    Annales Societatis Geologorum Poloniae
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Trace fossils in the Cretaceous-Eocene flysch of the Sinop-Boyabat Basin, Central Pontides, Turkey
    Autorzy:
    Uchman, A.
    Janbu, N. E.
    Nemec, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/191637.pdf
    Data publikacji:
    2004
    Wydawca:
    Polskie Towarzystwo Geologiczne
    Tematy:
    ichnology
    Nereites ichnofacies
    bathymetry
    turbidites
    tempestites
    rift
    foreland
    Opis:
    Sixty six ichnotaxa have been recognized in Barremian-Lutetian deep-marine deposits of the Sinop- Boyabat Basin, north-central Turkey, which evolved from a backarc rift into a retroarc foreland, with two episodes of major shallowing. The blackish-grey shales of the Çađlayan Fm (Barremian-Cenomanian) contain low- diversity traces fossils of mobile sediment feeders influenced by low oxygenation. One of the oldest occurrences of Scolicia indicates early adaptation to burrowing in organic-rich mud. The "normal" flysch of the Coniacian- Campanian Yemişliçay Fm bears a low-diversity Nereites ichnofacies influenced by volcanic activity. The Maastrichtian-Late Palaeocene carbonate flysch of the Akveren Fm contains a Nereites ichnofacies of moderate diversity, which is impoverished in the uppermost part, where tempestites indicate marked shallowing. The overlying variegated muddy flysch of the Atbaşý Fm (latest Palaeocene-earliest Eocene) bears an impoverished Nereites ichnofacies, which is attributed to oligotrophy and reduced preservation potential. The sand-rich silici-clastic flysch of the Kusuri Fm (Early-Middle Eocene) bears a high-diversity Nereites ichnofacies, except for the topmost part, where tempestites and littoral bioclastic limestone reflect rapid shallowing due to the tectonic closure of the basin. The turbiditic channel-fill and proximal lobe facies show a reduced trace-fossil diversity, but abundant Ophiomorpha , which is typical of the Ophiomorpha rudis sub-ichnofacies of the Nereites ichnofacies. The high abundance of Ophiomorpha in the Kusuri Fm and its low abundance in the Akveren Fm are related to plant detritus supply. The Kusuri turbiditic system was fed by a large delta, supplying rich plant detritus, whereas the Akveren system was fed by a carbonate ramp that supplied little or no such material. The extension of the Nereites ichnofacies into the tempestite-bearing neritic deposits at the top of both the Akveren and Kusuri formations indicates the capacity of the deep-water ichnofauna to survive in a rapidly-shoaling restricted basin. Only the topmost shoreface sandstones of the Akveren Fm show sporadic Ophiomorpha ? nodosa, a typical shallow-marine trace fossil.
    Źródło:
    Annales Societatis Geologorum Poloniae; 2004, 74, No 2; 197-235
    0208-9068
    Pojawia się w:
    Annales Societatis Geologorum Poloniae
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Lacustrine trace fossils and environmental conditions in the Early Miocene Ermenek Basin, southern Turkey
    Autorzy:
    Uchman, A.
    Nemec, W.
    Ilgar, A.
    Messina, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/191724.pdf
    Data publikacji:
    2007
    Wydawca:
    Polskie Towarzystwo Geologiczne
    Tematy:
    bioturbation
    Vagorichnus
    intramontane lake
    tempestites
    turbidites
    Central Taurides
    Opis:
    The Early Miocene lacustrine succession of the Ermenek Basin, an intramontane graben in southern Anatolia, consists of hemipelagic, variably calcareous mudstones and pelagic marlstones densely interspersed with tempestite sandstone sheets, subordinate turbidite sandstone sheets and sporadic layers of evaporitic limestone. The marly lake was hydrologically closed and mainly no deeper than 10 m, with the mean fairweather wave base at 1.5 m and storm wave base around 5 m. The deposits abound in trace fossils, including Vagorichnus cf. anyao (its second recognized occurrence), endichnial ferruginous ribbons, large tubular structures, oblique cylinders, small discontinuous ridges, undulating ridges, planar wall structures and a range of other bioturbational features. The tempestites and turbidites show both pre-and post-event trace fossils, with recognizable mixed and transitional layers similar as reported from marine tempestites and turbidites. The trace fossils constitute an impoverished Mermia ichnofacies indicating a considerable environmental stress. The lake salinity fluctuated, and the stress factor is attributed to the extreme environmental conditions (increased salinity and unusual water chemistry) caused by episodes of brackishness due to decreases in rainfall and increases in evaporation. Freshwater conditions are indicated by benthic ostracods and mollusc shells in offshore mudstones and by gastropod shells in coastal coal deposits, whereas marly layers contain only the ostracod species Miocyprideis glabra asulcata, implying mesohaline to polyhaline conditions.
    Źródło:
    Annales Societatis Geologorum Poloniae; 2007, 77, No 2; 123-139
    0208-9068
    Pojawia się w:
    Annales Societatis Geologorum Poloniae
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Trace fossils from Silurian and Devonian turbidites of the Chauvay area, southern Tien Shan, Kyrgyzstan
    Autorzy:
    Warchoł, M.
    Leszczyński, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/191868.pdf
    Data publikacji:
    2009
    Wydawca:
    Polskie Towarzystwo Geologiczne
    Tematy:
    Tien Shan
    Kyrgyzstan
    Silurian-Devonian
    turbidites
    trace fossils
    Opis:
    The siliciclastic turbidite successions (Pul’gon and Dzhidala Formations) that crop out in the eastern part of the Chauvay River valley, are marked on geological maps as a belt of terrigenous deposits of Silurian-Devonian age. They resemble deposits of overbank areas and depositional lobes of deep sea fans, and display common trace fossils particularly on lower surfaces of sandstone beds. Sixteen ichnotaxa representing four morphological groups have been distinguished. The trace fossil assemblages suggest their affiliation to the Nereites ichnofacies. Various branched, preturbidite forms predominate in both examined units, although the assemblages of individual units differ slightly in composition. In the Pulg’on Formation, small, densely distributed burrows commonly occur on lower surfaces of sandstone beds. Shallow burrowing depth together with relatively low diversity trace fossil assemblages indicate lowered oxygenation of the sea floor.
    Źródło:
    Annales Societatis Geologorum Poloniae; 2009, 79, No 1; 1-11
    0208-9068
    Pojawia się w:
    Annales Societatis Geologorum Poloniae
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Trinity Peninsula Group (Permo-Triassic?) at Hope Bay, Antarctic Peninsula
    Autorzy:
    Birkenmajer, Krzysztof
    Powiązania:
    https://bibliotekanauki.pl/articles/2052753.pdf
    Data publikacji:
    1992
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    West Antarctica
    Permo-Triassic (?)
    marine turbidites
    structure
    lithostratigraphy
    Źródło:
    Polish Polar Research; 1992, 13, 3-4; 215-240
    0138-0338
    2081-8262
    Pojawia się w:
    Polish Polar Research
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Facies analysis of the Silurian shale-siltstone succession in Pomerania (northern Poland)
    Autorzy:
    Jaworowski, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/2059457.pdf
    Data publikacji:
    2000
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    northern Poland
    Silurian
    submarine silty debrites
    turbidites
    exoflysch
    Opis:
    The Silurian deposits of Pomerania occur in the foreland of the Pomeranian Caledonides which are the SE continuation of the Danish-North-German Caledonides. The Silurian sequence in Pomerania is represented largely by graptolitic clay- and mud-shales deposited in a hemipelagic environment. From the Wenlock through Late Ludlow, slow deposition of hemipelagic clays and muds was repeatedly interrupted by silty debris flows and turbidity currents. Many of the siltstone interbeds were reworked by bottom currents. Clastic material was sourced from the Caledonian accretionary prism stretching along the collision zone of Baltica and East Avalonia. The Silurian shale-siltstone succession in Pomerania represents a Caledonian exoflysch i.e. syn-collision clastics accumulated in a foredeep developed on the East European Craton. The diachronous appearance of siltstone interbeds in the graptolitic shales indicate that collision between Baltica and East Avalonia was associated with sinistral strike-slip movement along the edge of the East European Craton.
    Źródło:
    Geological Quarterly; 2000, 44, 3; 297-315
    1641-7291
    Pojawia się w:
    Geological Quarterly
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Review of Miocene shallow marine and lacustrine depositional environments in Northern Croatia
    Autorzy:
    Malvić, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/2059402.pdf
    Data publikacji:
    2012
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    Pannonian Sea
    Pannonian Lakes
    Paratethys
    Miocene
    alluvial fans
    turbidites
    Opis:
    The Neogene and Quaternary depositional and structural characteristics of the southwestern Croatian Pannonian Basin System (CPBS) are unique within the Pannonian Basin System. Due to its position at the basin margin, the area was covered by shallow and partially isolated parts of the Pannonian Sea in the Badenian (Middle Miocene). Later, in the Pannonian and Pontian ages, the area contained several brackish lakes, the largest being Sava Lake and Drava Lake. Tectonic events, sedimentation and depositional mechanisms occurring during the Neogene in the CPBS have revealed that those areas can be considered as former shallow seas or lakes dominated by clastic sedimentation. Marine coarse-grained clastic sedimentation took place during the Badenian, with local sources of material and numerous alluvial fans developed during the first transtensional phase. In the Pannonian and Pontian (Late Miocene), sediments were deposited by turbidity currents from a single, distal material source located in the Eastern Alps during the second transtensional tectonic phase.
    Źródło:
    Geological Quarterly; 2012, 56, 3; 493--504
    1641-7291
    Pojawia się w:
    Geological Quarterly
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The contribution of Stanisław Dżułyński to flysch sedimentology: A 'Western' perspective
    Autorzy:
    Kelling, G.
    Walton, E. K.
    Simpson, F.
    Powiązania:
    https://bibliotekanauki.pl/articles/191704.pdf
    Data publikacji:
    2007
    Wydawca:
    Polskie Towarzystwo Geologiczne
    Tematy:
    sedimentary structures
    turbidites
    Carpathian flysch
    laboratory flume studies
    knowledge transfer
    Opis:
    Abstract: In his ground-breaking research on the sedimentary structures of turbidites, Stanisław Dżułyński demonstrated and took to new levels of accomplishment the defining attributes of the Kraków School of flysch sedimentology established by Marian Książkiewicz at the Jagiellonian University. These attributes included a meticulous approach to fieldwork, the ability to recognize the scalar and vector relationships of diverse sedi- mentary features, a working knowledge of several languages, a capacity to describe systematically structures that had previously received scant attention in the world literature of geology, and innovation in the transfer of scientific knowledge. Dżułyński also added elements that were distinctively his own: a highly inventive approach to the replication of turbidite sedimentary structures in laboratory flumes, an openness to new ideas, boundless enthusiasm for his chosen field, and an exuberantly outgoing personality. In spite of worldwide recognition for his numerous and wide-ranging achievements in geology, he viewed himself first and foremost as one of the senior students of Marian Książkiewicz. In this role, Dżułyński utilised every opportunity to present with great insight and objectivity the work of the Kraków School, enthusiastically shared his extensive knowledge of sedimentology with experienced colleagues and new acquaintances alike and, in particular, gave generous encouragement to young researchers.
    Źródło:
    Annales Societatis Geologorum Poloniae; 2007, 77, No 2; 93-103
    0208-9068
    Pojawia się w:
    Annales Societatis Geologorum Poloniae
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Sedimentary response to tectonic uplift of the Dukla basin margin recorded at Skrzydlna – the Menilite Beds (Oligocene), Outer Carpathians, S Poland
    Autorzy:
    Siemińska, A.
    Starzec, K.
    Godlewski, P.
    Wendorff, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/184565.pdf
    Data publikacji:
    2018
    Wydawca:
    Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
    Tematy:
    tectonics
    sedimentation
    MTD
    Mass Transport Deposit
    turbidites
    Menilite Beds
    Carpathians
    Opis:
    The Menilite Beds (Oligocene of Polish Flysch Carpathians) at Skrzydlna crops out in a structurally complex zone of the Fore-Magura Unit, which is tectonically overridden by Magura Nappe thrust form the S. The exposed sedimentary suite, representing the Dukla Basin, consists of fine-grained, well organised strata deposited in a low-energy, deep marine basin, which are abruptly overlain by poorly organised, coarse sandy conglomerate that forms a Mass Transport Deposit (MTD) complex. The MTD contains large boulders of extrabasinal rocks, massive sandstone beds with intrabasinal mudstone clasts, and slump sheets of sandstones. Above rests a fining- upwards sequence of sandstone beds interlayered with mudstones. The fine-grained facies reappear above to terminate the exposed succession. Erosional contacts and rapid facies changes, both vertical and lateral, are characteristic for the MTD unit. The sandstone-mudstone unit above contains laterally migrating erosional channels filled with massive sandy conglomerate in the lower part. Turbidites of varying density and completeness of internal structures that occur above are accompanied by an association of mixed facies including large-scale dune cross-bedding. Mineralogically, the sandstones are quartz arenites, sub-lithic arenites and wackes. Calcarenite grains – bioclasts, micrite and marl occur in substantial proportions only in the uppermost part of the succession. The point-counting data plotted on Qm-F-Lt diagram are clustered within the recycled fields: quartzose and transitional. Mineralogical maturity of the sandstones has the tendency to decrease from the sub-MTD strata upwards via the MTD unit to the lower part of the sandstone-mudstone complex; then it increases to the youngest sandstone beds with carbonate grains. These tendencies, associated with sedimentary features of the succession, reflect rapid uplift, emergence and progressive erosion of the terrigenous detritus source area, followed by tectonic stabilisation reflected by the appearance of the “carbonate factory”.
    Źródło:
    Geology, Geophysics and Environment; 2018, 44, 2; 231-244
    2299-8004
    2353-0790
    Pojawia się w:
    Geology, Geophysics and Environment
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Local sediment sources and palaeoflow directions in Upper Miocene turbidites of the Pannonian Basin System (Croatian part), based on mapping of reservoir properties
    Autorzy:
    Novak-Zelenika, K.
    Velić, J.
    Malvić, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/2060013.pdf
    Data publikacji:
    2013
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    Sequential Indicator Simulations
    Upper Miocene sandstones
    turbidites
    Croatia
    Sava Depression
    reservoirs
    Opis:
    The source of the clastic sediments in the Croatian part of the Pannonian Basin System (CPBS) during the Late Pannonian and Early Pontian was the Eastern Alps. Clastic sediments were redeposited several times before they reached the Sava Depression. The depositional environment and sediment transport mechanisms have been subject to detailed analysis described in many publications, and this study builds on previous research. We have carried out geostatistical mapping of selected Upper Pannonian and Lower Pontian reservoir variables of the Kloštar Field, located to the west of the Moslavačka gora Mt. (Croatia). This has shown that the Moslavačka gora Mt. was a secondary, local source of sediment, in contrast to the previous interpretation of a single, distant clastic source (Eastern Alps) for the CPBS during the Late Miocene. As the mineralogical composition of the Moslavačka gora Mt. and the Eastern Alps is very similar, the dominant direction of turbidity currents obtained by sequential indicator simulations are used to suggest that a modest amount of detritus was eroded from the Moslavačka gora Mt. and mixed with detritus sourced from the Eastern Alps.
    Źródło:
    Geological Quarterly; 2013, 57, 1; 17--30
    1641-7291
    Pojawia się w:
    Geological Quarterly
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Bioturbation structures in the Holovnia Siliceous Marls (Turonian-lower Santonian) in Rybotycze (Polish Carpathians)
    Autorzy:
    Leszczyński, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/191521.pdf
    Data publikacji:
    2003
    Wydawca:
    Polskie Towarzystwo Geologiczne
    Tematy:
    trace fossils
    carbonate turbidites
    Turonian-lower Santonian
    Skole Nappe
    Carpathians
    Polska
    Opis:
    The Holovnia Siliceous Marls represent carbonate turbidites interbedded with non-calcareous pelagic/hemipelagic shales. This study reports on bioturbation pattern, trace fossil assemblage and distribution of bioturbation structures, i.e. structures resulting from the life activity of organisms in general, in the succession exposed in the village of Rybotycze. 20 ichnospecies were identified, with one new ichnogenus (Squamichnus) and one new species (Squamichnus acinaceformis). The ichnofossils represent nearly exclusively fodinichnia produced close to the seafloor, below calcite compensation depth. Shallow location of anoxic pore waters is indicated to be responsible for relatively shallow bioturbation depth whereas variability in frequency of turbidite sedimentation and petrographic composition of turbidites is suggested as the chief control on the vertical distribution of the bioturbation structures in the succession.
    Źródło:
    Annales Societatis Geologorum Poloniae; 2003, 73, No 2; 103-122
    0208-9068
    Pojawia się w:
    Annales Societatis Geologorum Poloniae
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Middle Miocene deposits in Carpathian Foredeep : facies analysis and implications for hydrocarbon reservoir prospecting
    Autorzy:
    Lis, P.
    Wysocka, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/191170.pdf
    Data publikacji:
    2012
    Wydawca:
    Polskie Towarzystwo Geologiczne
    Tematy:
    facies analysis
    littoral
    tidal
    shoreface
    neritic slope
    turbidites
    Markov chain analysis
    Opis:
    This sedimentological study was based on well cores from the Polish and Ukrainian parts of the Carpa- thian Foredeep. It revealed general heterogeneity of facies in the middle Miocene of the sedimentary succession in the basin. Fourteen sedimentary facies were distinguished and their origin was interpreted: massive, non-graded sandstones; normal-graded, massive sandstones, with and without a stratified uppermost part; hydroplastically deformed sandstones; planar-parallel-stratified sandstones; trough-cross-stratified sandstones; ripple-cross-lami- nated sandstones; heterolithic deposits, composed of thinly interlayered sandstone and mudstone; massive and laminated mudstones; and basal gypsum/anhydrite evaporites, often intercalated with mudstone. Four main modalities of vertical facies organization were recognized and attributed to the following environments: (1) the mid-late Badenian, shoal-water, evaporitic environment that preceded the latest Badenian–early Sarmatian, main phase of foredeep development; (2) a littoral, tidal environment of the inner parts of storm-influenced, coastal bays and tidal flats or possibly spit-sheltered lagoons; (3) a wave-dominated, littoral, sandy environment, considered to be shoreface, extended by waves, in front of advancing deltas; and (4) a neritic to subneritic, muddy, offshore slope, characterized by frequent incursions of tempestite and turbidite sand. The study contributed to a better understanding of the mid-Miocene depositional systems in the basin, with significant implications for ongoing hydrocarbon exploration. Interpretations of the origins of potential reservoir sandstones provided important information on their possible stratigraphic distribution in the basin fill. The potential, economic importance of stratigraphic hydrocarbon traps underscored the urgent need for a full-scale facies analysis and fully cored wells in strategic parts of the basin.
    Źródło:
    Annales Societatis Geologorum Poloniae; 2012, 82, 3; 239--253
    0208-9068
    Pojawia się w:
    Annales Societatis Geologorum Poloniae
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Successive stages of calcitization and silicification of Cenomanian spicule-bearing turbidites based on microfacies analysis, Polish Outer Carpathians
    Autorzy:
    Bąk, B.
    Górny, Z.
    Bąk, K.
    Wolska, A.
    Stożek, B.
    Powiązania:
    https://bibliotekanauki.pl/articles/191355.pdf
    Data publikacji:
    2015
    Wydawca:
    Polskie Towarzystwo Geologiczne
    Tematy:
    calcitization
    silicification
    sponge spicules
    spicule-bearing turbidites
    cherts
    Cenomanian
    Outer Carpathians
    Opis:
    Mid-Cretaceous turbidites with large proportions of sponge spicules are widely distributed in the Silesian Nappe of the Outer Carpathians, giving rise to diversified types of sediments, from spiculites to spicule-bearing siliciclastics and calcarenites. Part of this succession, Middle–Late Cenomanian in age, was transformed into cherts. A microfacies study showed that these turbidite sediments underwent several stages of calcitization and silicification, which took place during Mid-Cretaceous times in different sedimentary environments, i.e., on a northern shelf bordering the Silesian Basin and on a deep sea floor. The first diagenetic changes were related to changes to the biotic components of the turbidite layers, dominated by siliceous sponge spicules. This process, which took place in the spiculitic carbonate mud on the shelves, was related to the calcitization of sponge spicules. Calcareous clasts and calcified skeletal elements also were corroded by bacteria. After transportation down the slope, the biogenic and siliciclastic particles were deposited below the carbonate compensation depth. Taphonomic processes on the basin floor and alternating phases of carbonate and silica cementations, recrystallization and dissolution occurred in these sediments and were related to the diversification in composition of successive turbidite layers. Silicification was related to the formation of quartz precipitates as fibrous chalcedony or microcrystalline quartz, which were derived from the earlier dissolution of amorphous silica, originating mostly from siliceous sponge spicules and radiolarian skeletons. However, a source of silica from hydrothermal vents was also possible. The initial silica precipitation could have taken place in a slightly acidic environment, where calcite was simultaneously dissolved. A number of silicification stages, visible as different forms of silica precipitate inside moulds after bioclasts, occur in the particular turbidite layers. They were related to changes in various elements of the pore-water profile after descending turbidity-current flows. A very low sedimentation rate during the Middle–Late Cenomanian in the Silesian Basin may have favoured the sequence of initial calcitization and silicification stages of the turbidite sediments.
    Źródło:
    Annales Societatis Geologorum Poloniae; 2015, 85, 1; 187-203
    0208-9068
    Pojawia się w:
    Annales Societatis Geologorum Poloniae
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Mid-Cretaceous spicule-rich turbidites in the Silesian Nappe of the Polish Outer Carpathians : radiolarian and foraminiferal biostratigraphy
    Autorzy:
    Bąk, M.
    Bąk, K.
    Ciurej, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/2058910.pdf
    Data publikacji:
    2005
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    Outer Carpathians
    middle-upper Cenomanian
    spicule-rich turbidites
    radiolarians
    foraminifers
    biostratigraphy
    Opis:
    Spicule-rich turbidites are widespread in mid-Cretaceous deep-water flysch of the Subsilesian and Silesian units in the Polish Outer Carpathians. The spicule-richmaterial with an admixture of numerous radiolarian and foraminiferal particles was supplied, together with siliciclastic material, from shallow environments, mostly from the northern margin of the Carpathian Basin. We present new data on the age of these deposits in the Silesian Nappe, where they are distinguished as the Mikuszowice Cherts. This unit is composed of mediumand thick-bedded siliciclastic to calcareous turbidites including bluish cherts in their middle and upper parts and of thin non-calcareous hemipelagic shales.We have studied radiolaria and foraminifera from hemipelagic sediments and spicule-rich turbidites, from two continuous sections in the Barnasiówka Range (BeskidWyspowyMts.) that included theMikuszowice Cherts (31 m thick) and their transition into the surrounding units. The age of the Mikuszowice Cherts was determined taking into account the following radiolarian datum events: (1) the occurrence of Praeconocaryomma lipmanae in the entire unit, (2) the FO (first occurrence) of Hemicryptocapsa tuberosa in the upper part of the unit, (3) the FO of Amphipyndax stocki close to the upper boundary of the unit, (4) the FO of Hemicryptocapsa prepolyhedra in the lowermost part of the overlying Barnasiówka Radiolarian Shale Formation. These datum events appear successively in theWestern Tethys successions within the Rotalipora cushmani planktonic foraminiferal Zone, which corresponds to the middle and upper Cenomanian (except for its uppermost part). The foraminiferal assemblages, in which such taxa as Rotalipora cf. cushmani, R. cf. greenhornensis, whiteinellids and Uvigerinammina praejankoi successively appear, confirm the mid-late Cenomanian age of the spicule-rich turbidites in the Silesian Nappe.
    Źródło:
    Geological Quarterly; 2005, 49, 3; 275--290
    1641-7291
    Pojawia się w:
    Geological Quarterly
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    K-Ar dating of bentonite diagenesis in accretionary-wedge turbidites : case study from Western Outer Carpathians
    Autorzy:
    Świerczewska, A.
    Paul, Z.
    Banaś, M.
    Tokarski, A. K.
    Powiązania:
    https://bibliotekanauki.pl/articles/191676.pdf
    Data publikacji:
    2015
    Wydawca:
    Polskie Towarzystwo Geologiczne
    Tematy:
    Bentonites
    illite-smectite
    K-Ar dating
    accretionary-wedge turbidites
    Western Outer Carpathians
    Opis:
    Sixteen bentonite layers of Eocene–Oligocene age were sampled at thirteen sites in accretionary-wedge turbidite sequences, in the three innermost nappes of the Western Outer Carpathians. K-Ar dating was carried out for five of these layers to obtain the maximum burial ages. All of the ages obtained are older than the stratigraphic ages of the host strata. This relationship is due to significant contamination of the bentonites with non-authigenic minerals. This contamination resulted from rapid sedimentation during synsedimentary folding, which is a common feature in accretionary wedges. It follows that the K-Ar dating of bentonite layers in the turbidite sequences of accretionary wedges should be largely restricted to the very distal facies of turbidites or to pelitic intercalations within the turbidites.
    Źródło:
    Annales Societatis Geologorum Poloniae; 2015, 85, 1; 177-185
    0208-9068
    Pojawia się w:
    Annales Societatis Geologorum Poloniae
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Interaction between turbidity currents and a contour current – a rare example from the Ordovician of Shaanxi province, China
    Autorzy:
    Li, Hua
    van Loon, A. J. (Tom)
    He, Youbin
    Powiązania:
    https://bibliotekanauki.pl/articles/950462.pdf
    Data publikacji:
    2019
    Wydawca:
    Uniwersytet im. Adama Mickiewicza w Poznaniu
    Tematy:
    contourites
    turbidites
    reworking
    Ordos basin
    Pingliang formation
    kontury
    turbidyty
    przeróbka
    zlewnia
    Ordos
    Pingliang
    Opis:
    The silty top parts of graded turbidites of the Late Ordovician Pingliang Formation, which accumulated along the southern margin of the Ordos Basin (central China), have been reworked by contour currents. The reworking of the turbidites can be proven on the basis of paleocurrent directions in individual layers: the ripple-cross-bedded sandy divisions of some turbidites show transport directions consistently into the downslope direction (consistent with the direction of other gravity flows), but in the upper, silty fine-grained division they show another direction, viz. alongslope (consistent with the direction that a contour current must have taken at the same time). Both directions are roughly perpendicular to each other. Moreover, the sediment of the reworked turbidites is better sorted and has better rounded grains than the non-reworked turbidites. Although such type of reworking is well known from modern deep-sea environments, this has rarely been found before in ancient deep-sea deposits. The reworking could take place because the upper divisions of the turbidites involved are silty and consequently relatively easily erodible, while the contour current had locally a relatively high velocity – and consequently a relatively large erosional capability – because of confinement within a relatively narrow trough.
    Źródło:
    Geologos; 2019, 25, 1; 15-30
    1426-8981
    2080-6574
    Pojawia się w:
    Geologos
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Facies heterogeneity of a deep-sea depositional lobe complex : case study from the Słonne section of Skole Nappe, Polish Outer Carpathians
    Autorzy:
    Łapcik, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/191784.pdf
    Data publikacji:
    2017
    Wydawca:
    Polskie Towarzystwo Geologiczne
    Tematy:
    deep-marine turbidites
    depositional lobes
    dynamic stratigraphy
    facies analysis
    mass flow deposits
    Upper Cretaceous
    Opis:
    This article reports on the first detailed study of the Skole Nappe’s Ropianka Formation in the Słonne outcrop section along river San. Lithological and micropalaeontological similarities indicate that the sedimentary succession correlates with the formation’s Wiar Member of Campanian–late Maastrichtian age. The sedimentary succession, more than 140 m thick, is interpreted as a deep-marine complex of turbiditic depositional lobes and the study reveals its sedimentary anatomy. Six component facies of sediment gravity-flow deposits and their stratigraphic grouping into four facies associations are recognized, with these latter considered to represent deposits of the lobe axial zone, lateral flank zone and featheredge fringe zone, as well as an interlobe outer-fringe zone. Semi-quantitative characterization and comparison of facies associations gives insight into the succession’s sedimentary heterogeneity. Six depositional lobes superimposed upon one another are recognized in the stratigraphic succession, and their pattern of vertical stacking is interpreted in terms of dynamic stratigraphy on the basis of the upward succession of facies associations. The stratigraphic arrangement of facies associations is attributed to autogenic morphodynamic changes within the evolving depositional system, although it cannot be precluded that also eustatic and local tectonic forcing came into play. The case study sheds more light on the sedimentary environment, sediment sourcing system and spatial depositional pattern in the Late Cretaceous Skole Basin, where the aggrading seafloor apparently oscillated around the lysocline depth that could be mid-bathyal at that time.
    Źródło:
    Annales Societatis Geologorum Poloniae; 2017, 87, 4; 301-324
    0208-9068
    Pojawia się w:
    Annales Societatis Geologorum Poloniae
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Contrasting styles of siliciclastic flysch sedimentation in the Upper Cretaceous of the Silesian Unit, Outer Western Carpathians : sedimentology and genetic implications
    Autorzy:
    Strzeboński, Piotr
    Powiązania:
    https://bibliotekanauki.pl/articles/2134836.pdf
    Data publikacji:
    2022
    Wydawca:
    Polskie Towarzystwo Geologiczne
    Tematy:
    Carpathian flysch
    debrites
    deep-sea deposits
    depositional system
    gravitational resedimentation
    Silesian Basin
    tractionites
    turbidites
    Late Cretaceous
    Opis:
    This study reports on a new set of sedimentological data and related interpretations of the Santonian–Campanian siliciclastic deposits in the Western Flysch Carpathians based on natural outcrops in the uppermost Godula Formation and lowermost Istebna Formation. The rationale was to confront the characteristics of this flysch succession with current controversies and state of knowledge on deep-water clastic sedimentation. The sedimentological analysis of the field data allowed for multi-scale synthetic classifications of the depositional components in the investigated flysch. The hierarchical and practical nature of the suggested classification schemes allows for their application to similar deposits in other regions. The siliciclastic deposits are products of gravity-driven terrigenous sediment redeposition via submarine slumps, debris flows, and turbidity currents. Sediment reworking by tractional bottom currents is considered as an accompanying factor. Point-sourced turbiditic fan lobe fringes from the submarine piedmont ramp and linearly supplied debritic covers along the slope apron are proposed as dominant. The innovative linking between the textural-structural descriptive features of the deposits and the critical determinants of specific sediment gravity-flow processes and architectural elements of the deepwater clastic depositional systems is a significant contribution to this research field.
    Źródło:
    Annales Societatis Geologorum Poloniae; 2022, 92, 2; 159--180
    0208-9068
    Pojawia się w:
    Annales Societatis Geologorum Poloniae
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Soft-sediment deformation structures in seismically affected deep-sea Miocene turbidites (Cilento Basin, southern Italy)
    Autorzy:
    Valente, A.
    Ślączka, A.
    Cavuoto, G.
    Powiązania:
    https://bibliotekanauki.pl/articles/94582.pdf
    Data publikacji:
    2014
    Wydawca:
    Uniwersytet im. Adama Mickiewicza w Poznaniu
    Tematy:
    high-density turbidites
    soft-sediment deformation structures
    seismites
    Apennines
    Cilento Group
    miocene
    Italy
    turbidyty
    struktury deformacji
    sejsmity
    Apeniny
    miocen
    Włochy
    Opis:
    Soft-sediment deformation structures (SSDS) are widespread in the upper part of the S. Mauro Formation (Cilento Group, Middle-Late Miocene). The succession is represented mainly by thick and very thick, massive, coarse-grained sandstones, deposited by rapid sedimentation of high-density turbidity currents. The most common SSDS are short pillars, dishes, sedimentary sills and convolutions. They occur mostly in the upper parts of sandstone beds. Vertical tubes of 4–5 cm in diameter and up to 50 cm long constitute the most striking structures. They begin in the middle part of sandstone beds, which are basically massive or contain faint dish structures. These tubes can bifurcate upwards and/ or pass into bedding-parallel veins or dikes. The vertical tubes sometimes form sand volcanoes on the then sedimentary surface. The SSDS are interpreted as the result of earthquake-triggered liquefaction and/or fluidisation of the turbidites that were affected by the seismic shocks. This implies that the deformed layers should be considered as seismites.
    Źródło:
    Geologos; 2014, 20, 2; 67-78
    1426-8981
    2080-6574
    Pojawia się w:
    Geologos
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Facies anatomy of a progradational submarine channelized lobe complex: semi-quantitative analysis of the Ropianka Formation (Campanian-Paleocene) in Hucisko Jawornickie section, Skole Nappe, Polish Carpathians
    Autorzy:
    Łapcik, Piotr
    Powiązania:
    https://bibliotekanauki.pl/articles/138693.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    deep-marine turbidites
    depositional lobes
    submarine channels
    dynamic stratigraphy
    facies analysis
    Markov chain analysis
    turbidyty
    loby depozycyjne
    kanały podmorskie
    stratygrafia dynamiczna
    analiza facjalna
    łańcuch Markova
    Opis:
    This study is a detailed lithofacies analysis of the Wiar and Leszczyny members of the deep-marine Ropianka Formation (Campanian–Paleocene) exposed in the Hucisko Jawornickie section of the Skole Nappe, Polish Carpathian Flysch. The sedimentary succession (>400 m thick) represents a channelized lobe complex that prograded at the base of submarine slope. Seven sedimentary facies are recognized as a record of the principal modes of sediment deposition. Based on their stratigraphic grouping and grain-size trends, six facies associations are distinguished as representing specific sub-environments of the depositional system: distributary channels, channel-mouth lobes, channel levees, crevasses and interlobe basin plain with crevasse splays. The individual facies associations are characterized statistically and their internal facies organization is analysed by the method of embedded Markov chains to reveal the time pattern of depositional processes. The environmental changes indicated by the vertical succession of facies associations are attributed to the autogenic processes of the distributary channel shifting within an aggrading lobe area and the lateral switching of depositional lobes. Eustatic influences are likely, but difficult to ascertain with poor biostratigraphic data. The bulk basinward advance of the base-of-slope system was probably due to a pulse of the tectonic narrowing of the synclinal Skole Basin.
    Źródło:
    Acta Geologica Polonica; 2019, 69, 1; 111-141
    0001-5709
    Pojawia się w:
    Acta Geologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Revised holostratigraphy of the Tithonian-Berriasian transition at Tré Maroua (Le Saix, Hautes-Alpes, SE France): study of a rejected Berriasian GSSP candidate
    Autorzy:
    Granier, Bruno R.C.
    Benzaggagh, Mohamed
    Ferry, Serge
    Powiązania:
    https://bibliotekanauki.pl/articles/27324248.pdf
    Data publikacji:
    2023
    Wydawca:
    Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
    Tematy:
    stratigraphy
    calpionellids
    saccocomids
    Tithonian
    Berriasian
    lithoclasts
    erosion
    debris flows
    turbidites
    Vocontian Trough
    stratygrafia
    kalpionellidy
    sakokomidy
    Tytonian
    Berriazjatycki
    litoklasty
    erozja
    spływają śmieci
    turbidyty
    Rynna Wokoncka
    Opis:
    The study of the Tithonian and lower Berriasian succession of Le Saix (Hautes-Alpes, France) has made it possible to better characterize the lithological succession at a former Berriasian GSSP candidate, its set of microfacies, the stratigraphic ranges of the main groups of marine plankton and therefore the calpionellid and saccocomid biozonations. On the lithological level, the Tithonian strata are characterized by thick-bedded breccias representing debris flows and related calciturbidites, whereas the Berriasian strata are typically white limestones. The lower part of the Berriasian is comprised of scattered intercalations of thin-bedded breccias and calciturbitides (including cryptic mud calciturbidites). In thin sections, the white limestones display mud- to wackestone textures and their allochems are mostly tiny bioclasts (e.g., radiolarians, calpionellids, saccocomids). Calciturbidites have wacke- to grainstone textures and their allochems are mostly pseudointraclasts and extraclasts, comprising various bioclasts and some ooids. Mud turbidites are made of micrograin-stones some yielding almost exclusively well-sorted calpionellids, which were previously erroneously interpreted as the signature of “explosions” or “blooms” of Calpionella alpina. Breccias are mostly lithoclastic floatstones with a matrix similar to that of the calciturbid- ites. Their lithoclasts are either extraclasts sensu stricto, i.e., material derived from updip shallow-water areas, or pseudointraclasts representing reworked subautochthonous material, i.e., mud- and wackestone lithoclasts with radiolarians, saccocomids and/or calpionellids. Radiolarians are common over the whole studied interval. Saccocomids are part of the dominating biota reported from the lower and lower upper Tithonian interval whereas calpionellids replace them in the uppermost Tithonian to lower Berriasian interval. Minor plank- tonic groups comprise calcareous dinoflagellates and Globochaete alpina; Iranopsis nov. group is also present. Intervals with saccocomid sections characteristic of zones 4-5 and zone 6 are respectively ascribed here to the lower Tithonian (4-5) and the lower upper Tithonian (6). The biozonation of the calpionellid group sensu lato allows identification of i) the Boneti Subzone of the chitinoidellids, ii) the Cras- sicollaria Zone, more specifically its Tintinnopsella-Intermedia (A1), Intermedia-Alpina (A2) and Brevis-Massutiniana (A3) subzones, and iii) the Alpina Zone, with its Alpina-Parvula (B1) and its Alpina-Remaniella (B2) subzones. On the basis of biostratigraphical and sedimentological data, most zonal boundaries prove to be hiatal, located at the erosional base of breccia or turbidite layers whereas the Tithonian/Berriasian stage boundary appears to be located at a strike-slip fault plane in the Tré Maroua section.
    Źródło:
    Volumina Jurassica; 2023, 21; 1--18
    1896-7876
    1731-3708
    Pojawia się w:
    Volumina Jurassica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
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