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Wyszukujesz frazę "cenoman" wg kryterium: Temat


Wyświetlanie 1-15 z 15
Tytuł:
On variation in Schloenbachia varians (J. Sowerby, 1817) from the Lower Cenomanian of western Kazakhstan
Autorzy:
Kennedy, W. J.
Powiązania:
https://bibliotekanauki.pl/articles/138676.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
ammonites
Schloenbachia
variation
Cenomanian
Cretaceous
Kazakhstan
amonity
mutacja
cenoman
kreda
Kazachstan
Opis:
An assemblage of 94 specimens of Schloenbachia varians (J. Sowerby, 1817) from the Lower Cenomanian Sharpeiceras schlueteri Subzone of the Mantelliceras mantelli Zone of the Besakty section in the Mangyshlak Mountains of western Kazakhstan includes 26 complete adults that range from to 59–174 mm in diameter. No size-related dimorphism was detected in the assemblage, which shows wide, continuous intraspecific variation. This is described in terms of five formae; from robust to gracile these are: ventriosa, varians sensu stricto, subtuberculata, intermedia, and subplana. The ratio of robust (ventriosa + varians sensu stricto) to gracile (subtuberculata + intermedia + subplana) individuals is 34% to 66%. The reference specimens of the formae and their synonyms are described and illustrated, and related to the Besakty material. The modification of adult body chamber ornament of all formae is documented, and Jakeiceras Cooper and Owen, 2011 is shown to be based on an adult of a passage form between forma subtuberculata and forma intermedia. The differences between Lower Cenomanian S. varians, lower Middle Cenomanian S. coupei (Brongniart, 1822), and upper Middle and lower Upper Cenomanian S. lymensis Spath, 1926b are described and illustrated.
Źródło:
Acta Geologica Polonica; 2013, 63, 4; 443-468
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trans-Tethyan correlation of the Lower-Middle Cenomanian boundary interval; southern England (Southerham, near Lewes, Sussex) and Douar el Khiana, northeastern Algeria
Autorzy:
Kennedy, W. J.
Gale, A. S.
Powiązania:
https://bibliotekanauki.pl/articles/139255.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Trans-Tethyan correlation
Cenomanian
ammonites
Algeria
England
cenoman
amonity
Algieria
Anglia
Opis:
A 480 m section of marls with widely separated levels of nodular limestone in the Fahdene Formation north of Bou Khadra in Tebessa Province, northeastern Algeria, spans the Lower/Middle Cenomanian boundary. A total of 30 ammonite species are present, of which two: Forbesiceras reversum and Calycoceras (Newboldiceras) algeriense are new. The fauna allows recognition of the Northwest European upper Lower Cenomanian Mantelliceras dixoni Zone, the succeeding lower Middle Cenomanian Cunningtoniceras inerme Zone, the Acanthoceras rhotomagense Zone and its subzones of Turrilites costatus and Turrilites acutus. The sequence of index species occurs in the same order in both north-eastern Tunisia and the Southerham Grey Pit in Sussex (and indeed elsewhere in North-west Europe), indicating these to be robust assemblage zones and subzones that can be recognised on both the north and south sides of the Tethys. Other occurrences of taxa that are common in both sections and regions are markedly different, and include the co-occurrence of Cunningtoniceras inerme (Pervinquière, 1907) with Acanthoceras rhotomagense (Brongniart, 1822) in the costatus Subzone in north-eastern Algeria and central Tunisia, the extension of Acompsoceras renevieri (Sharpe, 1857) into the lower Middle Cenomanian in north-eastern Tunisia, whilst the acme of Turrilites scheuchzerianus Bosc, 1801, is in the dixoni Zone in Northwest Europe, and in the inerme Zone in northeasten Algeria and adjacent parts of Central Tunisia. These differences are not a result of collection failure or non-preservation, but must rather reflect environmental controls on occurrence and abundance.
Źródło:
Acta Geologica Polonica; 2017, 67, 1; 75-108
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Taxonomy and taphonomy of Cenomanian (Upper Cretaceous) nautilids from Annopol, Poland
Autorzy:
Machalski, M.
Wilmsen, M.
Powiązania:
https://bibliotekanauki.pl/articles/139221.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
nautilids
condensed deposits
taphonomy
cenomanian
Cretaceous
Annopol
Polska
tafonomia
cenoman
kreda
Polska
Opis:
A nautilid faunule of seven specimens, comprising Eutrephoceras bouchardianum (d’Orbigny, 1840), Cymatoceras deslongchampsianum (d’Orbigny, 1840), and Cymatoceras tourtiae (Schlüter, 1876) is described from a condensed middle Cenomanian interval at Annopol, Poland. C. tourtiae is recorded for the first time in Poland. The studied material consists of reworked phosphatised internal moulds of phragmocones, which may be of early or middle Cenomanian age, given the stratigraphic range of the associated ammonites. The nautilid moulds vary in inferred mode of infilling, and in intensity of abrasion, bioerosion and mineralisation. The sediment entered the phragmocones in two ways: 1) through punctures in the shell, the result of bioerosion or mechanical damage; 2) through siphonal openings by intracameral currents. In contrast to the fossil moulds from the Albian phosphorites of Annopol, which originated via direct precipitation of apatite around and/or inside fossils, the present nautilid moulds seem to have originated through secondary phosphatisation of the initially calcareous moulds. Diversity of taphonomic signatures in nautilid material from the middle Cenomanian interval at Annopol is compatible with the complex, multievent depositional scenario proposed for this level.
Źródło:
Acta Geologica Polonica; 2015, 65, 4; 495-506
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sharpeiceras australe sp. nov., replacement name for Sharpeiceras falloti Kennedy, 2013, non Collignon, 1931
Autorzy:
Kennedy, W. J.
Powiązania:
https://bibliotekanauki.pl/articles/138845.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
ammonites
Cenomanian
Cretaceous
Madagascar
South Africa
amonity
cenoman
kreda
Madagaskar
Republika Południowej Afryki
Opis:
Sharpeiceras australe sp. nov. is proposed as the replacement name for Sharpeiceras falloti Kennedy, 2013, non Collignon, 1931, from the Lower Cenomanian of the Morondavo Basin, Madagascar.
Źródło:
Acta Geologica Polonica; 2014, 64, 1; 109-111
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Isolated pliosaurid teeth from the Albian-Cenomanian (Cretaceous) of Annopol, Poland
Autorzy:
Madzia, D.
Machalski, M.
Powiązania:
https://bibliotekanauki.pl/articles/139304.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Polyptychodon
Plesiosauria
Pliosauridae
teeth
albian
cenomanian
Annopol
Polska
plezjozaury
uzębienie
alb
cenoman
Polska
Opis:
Brachauchenine pliosaurids were a cosmopolitan clade of macropredatory plesiosaurs that are considered to represent the only pliosaurid lineage that survived the faunal turnover of marine amniotes during the Jurassic–Cretaceous transition. However, the European record of the Early to early Late Cretaceous brachauchenines is largely limited to isolated tooth crowns, most of which have been attributed to the classic Cretaceous taxon Polyptychodon. Nevertheless, the original material of P. interruptus, the type species of Polyptychodon, was recently reappraised and found undiagnostic. Here, we describe a collection of twelve pliosaurid teeth from the upper Albian–middle Cenomanian interval of the condensed, phosphorite-bearing Cretaceous succession at Annopol, Poland. Eleven of the studied tooth crowns, from the Albian and Cenomanian strata, fall within the range of the morphological variability observed in the original material of P. interruptus from the Cretaceous of England. One tooth crown from the middle Cenomanian is characterized by a gently subtrihedral cross-section. Similar morphology has so far been described only for pliosaurid teeth from the Late Jurassic and Early Cretaceous. Even though it remains impossible to precisely settle the taxonomic distinctions, the studied material is considered to be taxonomically heterogeneous.
Źródło:
Acta Geologica Polonica; 2017, 67, 3; 393-403
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Upper Albian, Cenomanian and Upper Turonian ammonite faunas from the Fahdène Formation of Central Tunisia and correlatives in northern Algeria
Autorzy:
Kennedy, William James
Powiązania:
https://bibliotekanauki.pl/articles/138843.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Ammonites
Cretaceous
Albian
Cenomanian
Turonian
Algeria
Tunisia
amonity
kreda
Alb
cenoman
Turon
Algieria
Tunezja
Opis:
Over 130 species are documented from the Upper Albian, Cenomanian and Upper Turonian Fahdène Formation and correlatives in Central Tunisia and northern Algeria, based on material described by Henri Coquand (1852, 1854, 1862, 1880), Léon Pervinquière (1907, 1910), Georges Dubourdieu (1953), Jacques Sornay (1955), and new collections. The material consists predominantly of limonitic nuclei, together with adults of micromorphs. There is no continuous record, and a series of faunas are recognised that can be correlated with the zonation developed in Western Europe. These are the Upper Albian Ostlingoceras puzosianum fauna, Lower Cenomanian Neostlingoceras carcitanense and Mariella (Mariella) harchaensis faunas, the upper Lower to lower Middle Cenomanian Turrilites scheuchzerianus fauna, Middle Cenomanian Calycoceras (Newboldiceras) asiaticum fauna, Upper Cenomanian Eucalycoceras pentagonum fauna, and the Upper Turonian Subprionocyclus neptuni fauna. Two new micromorph genera are described, Coquandiceras of the Mantelliceratinae and Cryptoturrilites of the Turrilitinae. Most of the taxa present have a cosmopolitan distribution, with a minority of Boreal, North American and endemic taxa.
Źródło:
Acta Geologica Polonica; 2020, 70, 2; 147-272
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Foraminiferal and radiolarian biostratigraphy of the youngest (Late Albian through Late Cenomanian) sediments of the Tatra massif, Central Western Carpathians
Autorzy:
Bąk, K.
Bąk, M.
Powiązania:
https://bibliotekanauki.pl/articles/138987.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Albian–Cenomanian
Tatra massif
biostratigraphy
foraminifera
radiolaria
alb
cenoman
Tatry
masyw
biostratygrafia
otwornice
promienice
Opis:
The foraminiferal and radiolarian biostratigraphy of selected sections of the Zabijak Formation, the youngest sediments of the Tatra massif (Central Western Carpathians), have been studied. Benthic foraminifers, mainly agglutinated species, occur abundantly and continuously throughout the studied succession, while planktic foraminifers are generally sparse. Five planktic and two benthic foraminiferal zones have been recognized. The marly part of the Zabijak Formation comprises the Pseudothalmanninella ticinensis (Upper Albian) through the Rotalipora cushmani (Upper Cenomanian) planktic foraminiferal zones, and the Haplophragmoides nonioninoides and Bulbobaculites problematicus benthic foraminiferal zones. The radiolarians were recognized exclusively in the Lower Cenomanian part of the formation.
Źródło:
Acta Geologica Polonica; 2013, 63, 2; 223-237
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zróżnicowanie warunków geotermalnych cenomańskiego systemu wodonośnego w rejonie Buska-Zdroju na przykładzie danych z nowych wierceń
Diversification of geothermal conditions of the cenomanian water-bearing system on the example of new drillings from the Busko-Spa region
Autorzy:
Gągulski, T.
Gorczyca, G.
Powiązania:
https://bibliotekanauki.pl/articles/203553.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Instytut Gospodarki Surowcami Mineralnymi i Energią PAN
Tematy:
wody geotermalne
Busko-Zdrój
system wodonośny
cenoman
gradient geotermiczny
geothermal waters
water-bearing system
cenomanian
geothermal degree
Opis:
Niecka miechowska stanowi obszar perspektywiczny pod względem występowania wód geotermalnych w obrębie cenomańskiego systemu wodonośnego. Wody takie zostały nawiercone w rejonie Buska-Zdroju w latach 2016–2017 trzema otworami OB-I, OB-II oraz OB-V. Otwory te zlokalizowane są po obu stronach dużej regionalnej dyslokacji zwanej uskokiem radzanowskim. Stwierdzona głębokość występowania wód geotermalnych w tym rejonie wynosi od 732,5 m (otw. OB-I) do 344,0 (otw. OB-II). Maksymalne temperatury wody na wypływie z otworów OB-I, OB-II i OB-V jakie uzyskiwano podczas badań wynoszą odpowiednio 27,2, 22,3 i 23,5°C. Są to wody chlorkowo-sodowe i chlorkowo-siarczanowo-sodowe, często jodkowe oraz siarczkowe. Pomimo tego, iż występują w obrębie utworów cenomanu, nie zawsze zawierają siarkowodór. Analiza wyników wykazała, że wyższy gradient geotermiczny występuje po południowej stronie uskoku Radzanowa. Jednak to obszar po północnej jego stronie, tj. rejon otworu OB-I, jest bardziej perspektywiczny pod kątem wykorzystania wód geotermalnych choćby do celów balneologicznych.
The Miechów Basin is a prospective area in terms of geothermal water occurrence within the Cenomanian aquifer. Three hydrogeological drillings (OB-I, OB-II, and OB-V) were made in the Busko-Zdrój area in 2016–2017. These geothermal water boreholes are located on both sides of a large regional dislocation called the Radzanów Fault. The geothermal water in this area occurs within the depth interval between 732.5 to 344.0 m, and the maximal temperatures at the outflow range from 21.5 to 27.2°C. These are chloride-sodium and chloride-sulfatesodium waters, often with iodide and sulphide. Despite the fact that these waters occur within the Cenomanian formations, they do not always contain hydrogen sulphide. The results of the studies showed that better geothermal conditions take place on the southern side of the Radzanów Fault.
Źródło:
Technika Poszukiwań Geologicznych; 2018, R. 57, nr 1, 1; 73-85
0304-520X
Pojawia się w:
Technika Poszukiwań Geologicznych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Biostratigraphy and Inoceramus survival across the Cenomanian–Turonian (Cretaceous) boundary in the Ram River section, Alberta, Canada
Autorzy:
Walaszczyk, I.
Plint, G. A.
Kennedy, W. J.
Powiązania:
https://bibliotekanauki.pl/articles/139253.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cenomanian–Turonian boundary
Mytiloides
ammonites
Inoceramus survival
biostratigraphy
Western Interior Basin
Canada
cenoman
turon
amonity
biostratygrafia
Kanada
Opis:
The biostratigraphy of the uppermost Cenomanian – Lower Turonian succession in the lower part of the Blackstone Formation exposed in the Ram River (Alberta, Canada), is interpreted in terms of the standard inoceramid/ ammonite zonation of the interval. Four successive inoceramid zones are recognized, those of Inoceramus pictus, Mytiloides puebloensis, M. kossmati, and M. mytiloides, as established in the stratotype section at Pueblo, Colorado. Their correlation to Pueblo is confirmed by ammonite data. The mid-Early Turonian zone of M. kossmati yielded an assemblage of Inoceramus, with species showing close affinity to the latest Cenomanian lineages. This multi-species sample proves the survival of Inoceramus lineages into the otherwise Mytiloides-dominated Early Turonian, and indicates that their disappearance from the record of the North American Western Interior was not because of their extinction. It is suggested that the apparent lack of Inoceramus in Lower Turonian strata is due to an extremely low population abundance in the Early Turonian sea.
Źródło:
Acta Geologica Polonica; 2016, 66, 4; 715-728
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lower and Middle Cenomanian ammonites from the Morondava Basin, Madagascar
Autorzy:
Kennedy, W. J.
Walaszczyk, I.
Gale, A. S.
Dembicz, K.
Praszkier, T.
Powiązania:
https://bibliotekanauki.pl/articles/139375.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Madagascar
Morondava Basin
cenomanian
ammonite succession
ammonite zonation
chronostratigraphy
Madagaskar
dorzecze
cenoman
amonit
sukcesja
podział na strefy
chronostratygrafia
Opis:
Lower and Middle Cenomanian ammonite assemblages have been collected on a bed-by-bed basis from localities at Vohipaly and Mahaboboka, Madagascar, as well as from outcrops around Berekata, all in the Morondava Basin, southwest Madagascar. These collections demonstrate the presence of the upper Lower Cenomanian Mantelliceras dixoni Zone and the lower Middle Cenomanian Cunningtoniceras inerme Zone of the north-western European standard sequence. These records indicate that the striking anomalies in the zonal assemblages of the classic divisions of the Madagascan Cenomanian are based on mixed assemblages, rather than a succession that differs radically from that elsewhere in the world. The dixoni Zone fauna is: Desmoceras cf. latidorsatum (Michelin, 1838), Pachydesmoceras kossmati Matsumoto, 1987, Forbesiceras sp., F. baylissiWright & Kennedy, 1984, F. largilliertianum (d'Orbigny, 1841), Mantelliceras cantianum Spath, 1926a, M. dixoni Spath, 1926b, M. mantelli (J. Sowerby, 1814), M. picteti Hyatt, 1903, M. saxbii (Sharpe, 1857), Sharpeiceras sp., S. falloti (Collignon, 1931), S. mocambiquense (Choffat, 1903), S. cf. florencae Spath, 1925, Acompsoceras renevieri (Sharpe, 1857), A. tenue Collignon, 1964, Calycoceras sp., Mrhiliceras lapparenti (Pervinquičre, 1907), Mariella (Mariella) stolizcai (Collignon, 1964), Hypoturrilites taxyfabreae (Collignon, 1964), Turrilites scheuchzerianus Bosc, 1801, Sciponoceras cucullatum Collignon, 1964, and Sciponoceras antanimangaensis (Collignon, 1964). The presence of Calycoceras in a Lower Cenomanian association represents a precocious appearance of a genus typically Middle and Upper Cenomanian in occurrence, and matches records from Tunisia. The inerme Zone yields a more restricted assemblage: Pachydesmoceras kossmati, Forbesiceras baylissi, Acanthoceras sp. juv., Cunningtoniceras cunningtoni (Sharpe, 1855) and Hypoturrilites taxyfabreae.
Źródło:
Acta Geologica Polonica; 2013, 63, 4; 625-655
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Facies changes in the Cenomanian (Cretaceous) of the northwestern Elbe Valley near Dresden (Saxony, Germany)
Autorzy:
Tröger, K. -A.
Powiązania:
https://bibliotekanauki.pl/articles/139129.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Upper Cretaceous
Cenomanian
Elbe Valley zone
biostratigraphy
lithostratigraphy
facies changes
tectonics
kreda górna
cenoman
dolina Łaby
biostratygrafia
litostratygrafia
tektonika
Opis:
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).
Źródło:
Acta Geologica Polonica; 2017, 67, 1; 135-144
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The stratigraphy of the mid Cretaceous (Albian) Upper Greensand Formation of the Wessex Basin and South West England, UK
Autorzy:
Gallois, R.
Owen, H.
Powiązania:
https://bibliotekanauki.pl/articles/139028.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
stratigraphy
Upper Greensand Formation
Cretaceous
Devon
Dorset
Wessex
Albian Stage
Cenomanian Stage
sequence stratigraphy
stratygrafia
formacja
kreda
dewon
alb
cenoman
Opis:
The Upper Greensand Formation, mostly capped by the Chalk, crops out on the edges of a broad, dissected plateau in Devon, west Dorset and south Somerset and has an almost continuous outcrop that runs from the Isle of Purbeck to the Vale of Wardour in south Wiltshire. The Formation is well exposed in cliffs in east Devon and the Isle of Purbeck, but is poorly exposed inland. It comprises sandstones and calcarenites with laterally and stratigraphically variable amounts of carbonate cement, glauconite and chert. The sedimentology and palaeontology indicate deposition in marginal marine-shelf environments that were at times subject to strong tidal and wave-generated currents. The formation of the Upper Greensand successions in the region was influenced by penecontemporaneous movements on major fault zones, some of which are sited over E-W trending Variscan thrusts in the basement rocks and, locally, on minor faults. Comparison of the principal sedimentary breaks in the succession with the sequence boundaries derived from world-wide sea-level curves suggests that local tectonic events mask the effects of any eustatic changes in sea level. The preserved fauna is unevenly distributed, both laterally and stratigraphically. Bivalves, gastropods and echinoids are common at some horizons but are not age-diagnostic. Ammonites are common at a few stratigraphically narrowly defined horizons, but are rare or absent throughout most of the succession. As a result, the age of parts of the succession is still poorly known.
Źródło:
Acta Geologica Polonica; 2018, 68, 2; 161-180
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A marker band folgen stratigraphy for the Cenomanian Chalk of England and its extension to northen Germany and France
Autorzy:
Jeans, Christopher Vincent
Powiązania:
https://bibliotekanauki.pl/articles/27323962.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
Cretaceous
cenomanian chalk
folge stratigraphy
marker bands
England
Northern Germany
Northwest France
Cenomanian–Turonian Anoxic Event
kreda
stratygrafia
Anglia
Niemcy Północne
północno-zachodnia Francja
cenoman
turon
Opis:
A novel stratigraphical scheme within the Folge Concept is described for the Cenomanian Chalk of England that is particularly suitable for investigating the regional changes in the lithofacies, diagenesis, geochemistry, and mineralogy of the sediments of the Chalk Sea leading up to the Cenomanian–Turonian Oceanic Anoxic Event. It is based on “isochronous” marker bands defined largely by calcitic macrofossil assemblages, and it avoids problems caused by the poor or non-preservation of ammonite assemblages and lateral changes in chalk lithofacies. Eight folgen are based on one, two, or more marker bands. Their sequences, lithologies and calcitic macrofossil assemblages are described from 33 exposures in the Northern Chalk Province of England. The folgen are named, in ascending order, the Belchford, Stenigot, Dalby, Bigby, Candlesby, Nettleton, Louth and Flixton, after villages in Lincolnshire and Yorkshire, England. The folgen are traced throughout the Transitional and Southern Chalk provinces of England. They are present in the Cenomanian chalk of northern Germany and northwest France. Regionally, an individual folge may display considerable vertical and lateral variation in general lithology and lithofacies whilst still maintaining their defining marker bands. The possibility of further refinement to the scheme is discussed.
Źródło:
Acta Geologica Polonica; 2023, 73, 2; 135--180
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Redox conditions, glacio-eustasy, and the status of the Cenomanian-Turonian Anoxic Event: new evidence from the Upper Cretaceous Chalk of England
Autorzy:
Jeans, Christopher V.
Wray, David S.
Williams, C. Terry
Bland, David J.
Wood, Christopher J.
Powiązania:
https://bibliotekanauki.pl/articles/1835600.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cretaceous
Cenomanian–Turonian Anoxic Event
eustatic lithocycles
glacial associations
redox conditions
cerium anomalies
carbon isotopes
NW Europe
Japan
kreda
cenoman
turon
asocjacje
redoks
izotopy węgla
północno-zachodnia Europa
Japonia
Opis:
The nature of the Cenomanian–Turonian Oceanic Anoxic Event (CTOAE) and its δ13 C Excursion is considered in the light of (1) the stratigraphical framework in which the CTOAE developed in the European shelf seas, (2) conclusions that can be drawn from new detailed investigations of the Chalk succession at three locations in England, at Melton Ross and Flixton in the Northern Province where organic-rich ‘black bands’ are present, and at Dover in the Southern Province (part of the Anglo-Paris Basin) where they are absent, and (3) how these conclusion fit in with the present understanding of the CTOAE. The application of the cerium anomaly method (German and Elderfield 1990) at Dover, Melton Ross and Flixton has allowed the varying palaeoredox conditions in the Chalk Sea and its sediments to be related to the acid insoluble residues, organic carbon, δ18O (calcite), δ13C (calcite), δ13C (organic matter), Fe 2+ and Mn2+ (calcite), and P/TiO2 (acid insoluble residue). This has provided evidence that the initial stages of the δ13C Excursion in England were related to (1) a drop of sea level estimated at between 45 and 85 metres, (2) influxes of terrestrial silicate and organic detritus from adjacent continental sources and the reworking of exposed marine sediments, and (3) the presence of three cold water phases (named the Wood, Jefferies and Black) associated with the appearance of the cold-water pulse fauna during the Plenus Cold Event. Conditions in the water column and in the chalk sediment were different in the two areas. In the Northern Province, cerium-enriched waters and anoxic conditions were widespread; the δ13C pattern reflects the interplay between the development of anoxia in the water column and the preservation of terrestrial and marine organic matter in the black bands; here the CTOAE was short-lived (~0.25 Ma) lasting only the length of the Upper Cenomanian Metoicoceras geslinianum Zone. In the Southern Province, water conditions were oxic and the δ13C Excursion lasted to the top of the Lower Turonian Watinoceras devonense Zone, much longer (~1.05 Ma) than in the Northern Province. These differences are discussed with respect to (1) the Cenomanian–Turonian Anoxic Event (CTAE) hypothesis when the ocean-continent-atmosphere systems were linked, (2) limitations of chemostratigraphic global correlation, and (3) the Cenomanian-Turonian Anoxic Event Recovery (CTOAER), a new term to define the varying lengths of time it took different oceans and seas to recover once the linked ocean-continent-atmosphere system was over. The possibility is considered that glacio-eustasy (the glacial control hypothesis of Jeans et al. 1991) with the waxing and waning of polar ice sheets, in association with the degassing of large igneous provinces, may have set the scene for the development of the Cenomanian-Turonian Anoxic Event (CTAE).
Źródło:
Acta Geologica Polonica; 2021, 71, 2; 103-152
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The late Cenomanian oyster Lopha staufferi (Bergquist, 1944) – the oldest ribbed oyster in the Upper Cretaceous of the Western Interior of the United States
Autorzy:
Hook, S. C.
Cobban, W. A.
Powiązania:
https://bibliotekanauki.pl/articles/138617.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cenomanian
oysters
U.S. Western Interior
Taxonomy
paleogeography
biostratigraphy
Sweepstake Routes
Zigzag Commissure
Twowells Tongue
Dakota Sandstone
cenoman
ostrygi
Środkowo-Zachodnie Stany Zjednoczone
systematyka
paleogeografia
biostratygrafia
Dakota
piaskowiec
Opis:
Lopha staufferi (Bergquist, 1944) is a medium-sized, ribbed, Late Cretaceous oyster with a slightly curved axis and a zigzag commissure; it appears suddenly and conspicuously in upper Cenomanian rocks in the Western Interior Basin of the United States. At maturity, the ribs on both valves thicken into steep flanks that allow the oyster to increase interior volume without increasing its exterior footprint on the seafloor. Lopha staufferi is the first (earliest) ribbed oyster in the Late Cretaceous of the Western Interior, but has no ancestor in the basin. It disappears from the rock record as suddenly as it appeared, leaving no direct descendent in the basin. In the southern part of the basin where it is well constrained, L. staufferi is restricted stratigraphically to the upper Cenomanian Metoicoceras mosbyense Zone (= Dunveganoceras conditum Zone in the north). Lopha staufferi has an unusual paleogeographic distribution, occurring in only two, widely scattered areas in the basin. It has been found at several localities near the western shoreline of the Late Cretaceous Seaway in west-central New Mexico and adjacent Arizona, and in localities 1,900 km (1,200 mi) to the northeast near the eastern shoreline in northeastern Minnesota, but nowhere in between. In west-central New Mexico and adjacent Arizona, L. staufferi is a guide fossil to the Twowells Tongue of the Dakota Sandstone.
Źródło:
Acta Geologica Polonica; 2016, 66, 4; 609-626
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
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