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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:
Integrated biostratigraphy and palaeoenvironments of the Upper Cretaceous in the Petrich section (Central Srednogorie Zone, Bulgaria)
Autorzy:
Pavlishina, Polina
Dochev, Docho
Wagreich, Michael
Koukal, Veronika
Powiązania:
https://bibliotekanauki.pl/articles/24024712.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
Upper Cretaceous
campanian
calcareous nannofossil
dinoflagellate cysts
inoceramids
biostratigraphy
palaeoenvironments
górna kreda
kampan
nanoplankton wapienny
cysty bruzdnicowe
inoceramy
biostratygrafia
paleośrodowisko
Opis:
The Upper Cretaceous succession (Coniacian to lowermost Maastrichtian, with focus on the Campanian) at Petrich, Central Srednogorie Zone in Bulgaria, is described and calibrated stratigraphically based on nannofossils, dinoflagellate cysts and inoceramids. The following standard nannofossil zones and subzones are identified: UC10-UC11ab (middle to upper Coniacian), UC11c-UC12-UC13 (uppermost Coniacian to Santonian), UC14a (lowermost Campanian), UC14bTP-UC15cTP (lower Campanian to ‘middle’ Campanian), UC15dTP-UC15eTP (upper Campanian), UC16aTP (of Thibault et al. 2016; upper part of the upper Campanian), and UC16b (Campanian-Maastrichtian boundary). The base of the Campanian is defined by the FO of Broinsonia parca parca (Stradner) Bukry, 1969 and Calculites obscurus (Deflandre) Prins and Sissingh in Sissingh, 1977 (a morphotype with a wide central longitudinal suture). The Areoligera coronata dinoflagellate cyst Zone (upper lower Campanian to upper upper Campanian) is identified, corresponding to the UC14bTP-UC16aTP nannofossil subzones. The inoceramid assemblage indicates the ‘Inoceramus’ azerbaydjanensis-‘Inoceramus’ vorhelmensis Zone, correlated within the interval of nannofossil subzones UC15dTP-UC15eTP. The composition of the dinoflagellate cyst assemblages and palynofacies pattern suggest normal marine, oxic conditions and low nutrient availability within a distal shelf to open marine depositional environment during the Campanian.
Źródło:
Acta Geologica Polonica; 2023, 73, 1; 33--62
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stratigraphy of the Albian-Cenomanian (Cretaceous) phosphorite interval in central Poland: a reappraisal
Autorzy:
Machalski, Marcin
Olszewska-Nejbert, Danuta
Wilmsen, Markus
Powiązania:
https://bibliotekanauki.pl/articles/24024713.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
Polska
Cretaceous
phosphorites
rare earth elements
biostratigraphy
sequence stratigraphy
Polska
kreda
fosforyty
metale ziem rzadkich
REE
biostratygrafia
stratygrafia sekwencji
Opis:
Several closely-spaced phosphorite beds stand out at the Albian–Cenomanian transition in the mid-Cretaceous transgressive succession at the northeastern margin of the Holy Cross Mountains, central Poland. They form a distinctive condensed interval of considerable stratigraphical, palaeontological, and economic value. Here, we correlate the classical section at Annopol with a recently investigated section at Chałupki. We propose a new stratigraphic interpretation of the phosphorite interval, based on lithological correlations, Rare Earth Elements and Yttrium (REE+Y) signatures of phosphorites, age-diagnostic macrofossils, and sequence stratigraphic patterns. This interval has long been considered as exclusively Albian in age. However, new macrofossil data allow us to assign the higher phosphorite levels at Annopol and Chałupki, which were the primary target for the phosphate mining, to the lower Cenomanian. In terms of sequence stratigraphy, the phosphorite interval encompasses the depositional sequence DS Al 8 and the Lowstand System Tract of the successive DS Al/Ce 1 sequence. The proposed correlation suggests that lowstand reworking during the Albian–Cenomanian boundary interval played an important role in concentrating the phosphatic clasts and nodules to exploitable stratiform accumulations. Our conclusions are pertinent to regional studies, assessments of natural resources (in view of the recent interest in REE content of the phosphorites), and dating of the fossil assemblages preserved in the phosphorite interval. On a broader scale, they add to our understanding of the formation of stratiform phosphorite deposits.
Źródło:
Acta Geologica Polonica; 2023, 73, 1; 1--31
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cysty Dinoflagellata z górnego kampanu i najniższego mastrychtu (górna kreda) profilu środkowej Wisły - stratygrafia i paleoekologia
Dinoflagellate cysts from the upper Campanian–lowermost Maastrichtian (Upper Cretaceous) of the Middle Vistula River section - stratigraphy and palaeoecology
Autorzy:
Nechwedowicz, Mariusz
Powiązania:
https://bibliotekanauki.pl/articles/20197905.pdf
Data publikacji:
2022
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
cysty bruzdnicowe
taksonomia
biostratygrafia
paleoekologia
zmiany poziomu morza
chłodzenie
Kampan
Mastrycht
górna kreda
środkowaj Wisła
Polska
dinoflagellate cysts
taxonomy
biostratigraphy
palaeoecology
sea-level changes
cooling
Campanian/Maastrichtian boundary
Upper Cretaceous
Middle Vistula River section
Polska
Opis:
Among the rich dinoflagellate cyst assemblages recovered from the upper Campanian-lowermost Maastrichtian succession of the Middle Vistula River section (central Poland), four taxa (Callaiosphaeridium bicoronatum, Odontochitina dilatata, Oligosphaeridium araneum and Samlandia paucitabulata) have been described as new. An analysis of the distribution of particular dinoflagellate cyst taxa enabled the development of a highly resolved biostratigraphic framework, calibrated against other biozonal schemes (based, among others, on inoceramid bivalves, ammonites and belemnites), formerly established for the succession. A comparison of the Middle Vistula River record with the dinoflagellate cyst ranges documented in other European successions enabled correlations with selected sections in Belgium, the Netherlands, southern Germany and northern Italy, and with the Campanian/Maastrichtian boundary stratotype section in Tercis les Bains, southwest France. A palaeoecological analysis of the dino- flagellate cyst assemblages and of other components of phytoplankton communities revealed a well-defined trend in sea-level fluctuations (likely of eustatic origin), and palaeoclimatic changes probably related to the latest Cretaceous cooling episode, as observed elsewhere.
Źródło:
Przegląd Geologiczny; 2022, 70, 10; 751-760
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Upper upper Albian (Mortoniceras rostratum Zone) cephalopods from Clansayes (Drôme, south-eastern France)
Autorzy:
Jattiot, Romain
Lehmann, Jens
Latutrie, Benjamin
Tajika, Amane
Vennin, Emmanuelle
Vuarin, Pauline
Brayard, Arnaud
Fara, Emmanuel
Trincal, Vincent
Powiązania:
https://bibliotekanauki.pl/articles/2086664.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
ammonites
Cretaceous
upper Albian
taxonomy
south-eastern France
shell chirality
amonity
kreda
alb
taksonomia
Francja południowo-wschodnia
chiralność
Opis:
We document an upper upper Albian (Mortoniceras rostratum Zone) cephalopod assemblage from Clansayes (Drôme, south-eastern France). Although fossils are rare in local exposures and in the single sampled level, a decade of intensive fossil collecting yielded 290 ammonite and 5 nautilid specimens. In total, we describe 1 species of nautilid and 24 species (within 17 genera) of ammonites, including 13 heteromorphs. Only two of these ammonite taxa were previously recorded from the upper upper Albian at Clansayes, which demonstrates the value of this fauna with regard to taxonomy, palaeobiology and palaeobiogeography. Based on morphological and biometric analyses performed on an extensive material (104 specimens), we discriminate two species for the heteromorphic ammonite genus Mariella Nowak, 1916 within the Mortoniceras rostratum Zone. In addition, we investigate shell chirality patterns in Mariella from the late Albian of southern France. Upon comparison of the Clansayes material with older material from the immediately underlying upper Albian Mortoniceras fallax Zone at the neighbouring Salazac locality, we identify an increase in the proportion of sinistral specimens. This observed increase in the frequency of sinistral Mariella specimens may hypothetically be part of a global evolutionary pattern, considering that nearly all documented younger Cenomanian Mariella (and more generally Cenomanian turrilitids) are sinistral.
Źródło:
Acta Geologica Polonica; 2022, 72, 2; 187--233
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On imperfectly known Hauterivian representatives of the families Holcodiscidae Spath, 1923 and Barremitidae Breskovski, 1977 in Butkov Quarry (Central Western Carpathians, Slovakia)
Autorzy:
Vašíček, Zdeněk
Klein, Jaap
Powiązania:
https://bibliotekanauki.pl/articles/2024043.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Early Cretaceous
ammonites
taxonomy
stratigraphy
Manín Unit
Carpathians
kreda wczesna
amonity
taksonomia
stratygrafia
Karpaty
Opis:
In Butkov Quarry, ammonites of the families Holcodiscidae Spath, 1923 and Barremitidae Breskovski, 1977 occur in the pelagic Lower Cretaceous pelagic deposits of the Manín Unit. This contribution discusses the taxonomy of both families and presents their distribution in the layered sequences of the quarry. The genus Spitidiscus Kilian, 1910 classified as a member of the Superfamily Perisphinctoidea Steinmann in Steinmann and Döderlein, 1890 is an important representative of the Holcodiscidae from a stratigraphic point of view. In areas where the zonal index Acanthodiscus radiatus (Bruguière, 1789) does not occur, as in Butkov Quarry, the first representatives of Spitidiscus indicate the base of the Hauterivian. The genus Plesiospitidiscus Breistroffer, 1947 was long regarded as a member of the Superfamily Desmoceratoidea Zittel, 1895. This superfamily was based on its type species, Eodesmoceras celestini (Pictet and Campiche, 1860), which is not Valanginian in age, as now clearly proven. As a consequence, this superfamily is considered invalid. Vermeulen and Lahondère (2011) proposed an alternative by selecting a suitable initial genus, namely Plesiospitidiscus, for the Family Barremitidae, Superfamily Barremitoidea Breskovski, 1977 (nom. transl. Vermeulen and Lahondère, 2011).
Źródło:
Acta Geologica Polonica; 2021, 71, 4; 433--451
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:
Campanian-Paleocene Jaworzynka Formation in its type area (Magura Nappe, Outer Carpathians)
Autorzy:
Waśkowska, Anna
Golonka, Jan
Starzec, Krzysztof
Cieszkowski, Marek
Powiązania:
https://bibliotekanauki.pl/articles/1835592.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Upper Cretaceous
Paleogene
lithostratigraphy
foraminifera
biostratigraphy
kreda górna
paleogen
litostratygrafia
otwornice
biostratygrafia
Opis:
The Campanian-Paleocene Jaworzynka Formation, a part of the Magura Nappe succession in the Polish Outer Carpathians, is described in terms of its detailed litho- and biostratigraphy. The formation stretches along the marginal part of the Siary Unit, from the Jaworzynka stratotype area in the Silesian Beskid Mts up to the Mszana Dolna area in the Beskid Wyspowy Mts. Its equivalent in the Moravskoslezské Beskydy Mts of the Czech Republic is the Soláň Formation. In the stratotype area, the formation displays complex structure. We distinguish four lithological units, i.e., Biotite Sandstone and Shale (I), Shale (II), Mutne Sandstone Member (III) and Thin-bedded Turbidite (IV) and provide the first detailed biostratigraphy of particular units. The first unit forms the most prominent part of the formation. It was deposited in the Middle Campanian-earliest Maastrichtian within the upper part of Caudammina gigantea Zone up to the lower part of the Rzehakina inclusa Zone. The second unit occurs only locally and its age is limited to the Maastrichtian, to the Rzehakina inclusa Zone. The third unit is composed of thick-bedded sandstones that in some parts may form more than the half of the total thickness of the formation. It is Late Maastrichtian-Danian in age and is placed in the upper part of the Rzehakina inclusa Zone and the lower part of the Rzehakina fissistomata Zone. It is usually covered by a thin package of thin-bedded turbiditic sandstone and shales of Danian-Thanetian age with foraminifera of the Rzehakina fissistomata Zone.
Źródło:
Acta Geologica Polonica; 2021, 71, 3; 345-370
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Roveacrinidae (Crinoidea, Articulata) from the Cenomanian and Turonian of North Africa (Agadir Basin and Anti-Atlas, Morocco, and central Tunisia): biostratigraphy and taxonomy
Autorzy:
Gale, Andrew Scott
Powiązania:
https://bibliotekanauki.pl/articles/1835587.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cretaceous
microcrinoids
correlation
North Africa
New taxa
kreda
korelacja
Afryka Północna
nowe taksony
Opis:
Successions exposed in the Agadir Basin (upper Albian to middle Turonian), in the Anti-Atlas (lower Turonian) in Morocco and in central Tunisia (Cenomanian–Turonian) yield abundant microcrinoids of the family Roveacrinidae, which are described and assigned to 32 species and formae, in ten genera. The following new taxa are described: Fenestracrinus gen. nov. with the type species F. oculifer sp. nov., Discocrinus africanus sp. nov., Styracocrinus rimafera sp. nov., Lebenharticrinus quinvigintensis sp. nov., L. zitti sp. nov., Euglyphocrinus cristagalli sp. nov., E. jacobsae sp. nov., E. truncatus sp. nov., E. worthensis sp. nov., Roveacrinus gladius sp. nov., R. solisoccasum sp. nov. and Drepanocrinus wardorum sp. nov. In addition, the new subfamily Plotocrininae is erected. The stratigraphical distribution of the taxa in two important localities, Taghazout in the Agadir Basin (Morocco) and Sif el Tella, Djebel Mhrila (central Tunisia), is provided. The faunas from the uppermost Albian and lowermost Cenomanian of the Agadir Basin are nearly identical to those recorded from central Texas, USA, some 5,300 km away, and permit a detailed correlation (microcrinoid biozones CeR1 and CeR2) to be established across the southern part of the Western Tethys, independently supported by new ammonite records. For the middle and upper Cenomanian, rather few detailed records of microcrinoids are available elsewhere, and the North African record forms the basis for a new zonation (CeR3–CeR6). The distribution of Turonian Roveacrinidae in North Africa is evidently very similar to that described in the Anglo-Paris Basin, and zones TuR1–3, TuR9, 10 and 14 are recognised for the first time in the Tethys.
Źródło:
Acta Geologica Polonica; 2020, 70, 3; 273-310
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Roveacrinidae (Crinoidea, Articulata) from the Cenomanian and Turonian of North Africa (Agadir Basin and Anti-Atlas, Morocco, and central Tunisia): biostratigraphy and taxonomy
Autorzy:
Gale, Andrew Scott
Powiązania:
https://bibliotekanauki.pl/articles/139298.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cretaceous
microcrinoids
correlation
North Africa
New taxa
kreda
korelacja
Afryka Północna
nowe taksony
Opis:
Successions exposed in the Agadir Basin (upper Albian to middle Turonian), in the Anti-Atlas (lower Turonian) in Morocco and in central Tunisia (Cenomanian–Turonian) yield abundant microcrinoids of the family Roveacrinidae, which are described and assigned to 32 species and formae, in ten genera. The following new taxa are described: Fenestracrinus gen. nov. with the type species F. oculifer sp. nov., Discocrinus africanus sp. nov., Styracocrinus rimafera sp. nov., Lebenharticrinus quinvigintensis sp. nov., L. zitti sp. nov., Euglyphocrinus cristagalli sp. nov., E. jacobsae sp. nov., E. truncatus sp. nov., E. worthensis sp. nov., Roveacrinus gladius sp. nov., R. solisoccasum sp. nov. and Drepanocrinus wardorum sp. nov. In addition, the new subfamily Plotocrininae is erected. The stratigraphical distribution of the taxa in two important localities, Taghazout in the Agadir Basin (Morocco) and Sif el Tella, Djebel Mhrila (central Tunisia), is provided. The faunas from the uppermost Albian and lowermost Cenomanian of the Agadir Basin are nearly identical to those recorded from central Texas, USA, some 5,300 km away, and permit a detailed correlation (microcrinoid biozones CeR1 and CeR2) to be established across the southern part of the Western Tethys, independently supported by new ammonite records. For the middle and upper Cenomanian, rather few detailed records of microcrinoids are available elsewhere, and the North African record forms the basis for a new zonation (CeR3–CeR6). The distribution of Turonian Roveacrinidae in North Africa is evidently very similar to that described in the Anglo-Paris Basin, and zones TuR1–3, TuR9, 10 and 14 are recognised for the first time in the Tethys.
Źródło:
Acta Geologica Polonica; 2020, 70, 3; 273-310
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The erratic rocks of the Upper Cretaceous Chalk of England: how did they get there, ice transport or other means?
Autorzy:
Jeans, Christopher V.
Platten, Ian M.
Powiązania:
https://bibliotekanauki.pl/articles/1835594.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cretaceous
chalk
erratics
gastroliths
fast ice
palaeogeography
NW Europe
kreda
eratyk
stały lód brzegowy
paleogeografia
Europa północno-zachodnia
Opis:
Rare erratic clasts - extraneous rock types - occur in the Upper Cretaceous Chalk, including a local basal facies, the Cambridge Greensand. The underlying Upper Albian Gault Clay and the Hunstanton Red Chalk Formations have also yielded erratics. The discovery of these erratics, their description and the development of hypotheses to explain their origins and significance are reviewed. They became the subject of scientific interest with the interpretation of a particularly large example “The Purley Boulder” by Godwin-Austen (1858) as having been transported to its depositional site in the Chalk Sea by drifting coastal ice. Thin section petrography (1930–1951) extended knowledge of their diverse provenance. At the same time the Chalk Sea had become interpreted as warm, so drifting ice was considered out of context, and the preferred agents of transport were entanglement in the roots of drifting trees, as holdfasts of floating marine algae, or as stomach stones of marine reptiles or large fish. Reconsideration of their occurrence, variable nature and sedimentary setting suggests that there are three zones in the English Chalk where erratics may be less rare (1) near the base of the Cenomanian in the Cambridge area, (2) the Upper Cenomanian-Middle Turonian in Surrey, and (3) the Upper Coniacian and Lower Santonian of Kent. The assemblage from each level and their sedimentary setting is subtly different. Present evidence suggests that the erratics found in the Upper Albian-Lower Cenomanian and the Upper Cenomanian-Middle Turonian zones represent shallow water and shoreline rocks that were transported into the Chalk Sea by coastal ice (fast-ice) that enclosed coastal marine sediments as it froze. The Upper Coniacian and Lower Santonian erratics from Rochester and Gravesend in Kent are gastroliths.
Źródło:
Acta Geologica Polonica; 2021, 71, 3; 287-304
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The proposal of a GSSP for the Berriasian Stage (Cretaceous System): Part 2
Autorzy:
Wimbledon, William A.P.
Reháková, Daniela
Svobodová, Andrea
Elbra, Tiiu
Schnabl, Petr
Pruner, Petr
Šifnerová, Krýstina
Kdýr, Šimon
Frau, Camille
Schnyder, Johann
Galbrun, Bruno
Vaňková, Lucie
Dzyuba, Oksana
Copestake, Philip
Hunt, Christopher O.
Riccardi, Alberto
Poulton, Terry P.
Bulot, Luc G.
De Lena, Luis
Powiązania:
https://bibliotekanauki.pl/articles/2060930.pdf
Data publikacji:
2020
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Cretaceous
GSSP
biostratigraphy
magnetostratigraphy
Vocontian Basin
Berriasian stages
Kreda
biostratygrafia
magnetostratygrafia
Opis:
In part 1 of this work we discussed the possibilities for the selection of a GSSP for the Berriasian Stage of the Cretaceous System, based on prevailing practical methods for correlation in that J/K interval, traditional usage and the consensus over the best boundary markers that had developed in the last forty years. This consensus has developed further, based on the results of multidisciplinary studies on numerous sites over the last decade. Here in Part 2 we give an account of the application of those results by the Berriasian Working Group (ISCS), and present the stratigraphic evidence that justifies the selection of the locality of Tré Maroua (Hautes-Alpes, SE France) as the proposed GSSP. We describe a 45 m-thick section in the Calcaires Blancs vocontiens – that part of the formation covering the calpionellid Chitinoidella, Remanei. Intermedia, Colomi, Alpina, Ferasini, Elliptica and Simplex biozones. The stratigraphic data collected here has been compiled as part of a wider comparative study of complementary Vocontian Basin sites (with localities at Charens, St Bertrand, Belvedere and Le Chouet). Evidence from Tré Maroua thus sits in this substantial regional biostratigraphic and magnetostratigraphic context. For the purposes of the GSSP definition, here we particularly concentrate on the unbroken sequence and biotic markers in the interval immediately below the boundary, the Colomi Subzone (covering circa 675,000 years), and immediately above, the Alpina Subzone (covering circa 725,000 years). Particularly significant fossil datums identified in the Tré Maroua profile are the primary basal Berriasian marker, the base of the Alpina Subzone (a widespread event marked by dominance of small Calpionella alpina, with rare Crassicollaria parvula and Tintinopsella carpathica): the base of the Berriasian Stage is placed at the base of bed 14, which coincides with the base of the Alpina Subzone. Secondary markers bracketing the base of the Calpionella Zone are the FOs of the calcareous nannofossil species Nannoconus wintereri, close below the boundary, and the FO of Nannoconus steinmannii minor, close above. The Tithonian/Berriasian boundary level occurs within M19n.2n, in common with many documented sites, and is just below the distinctive reversed magnetic subzone M19n.1r (the so-called Brodno reversal). We present data which is congruent with magnetostratigraphic and biostratigraphic data from other key localities in France and in wider regions (Le Chouet, Saint Bertrand, Puerto Escaño, Rio Argos, Bosso, Brodno, Kurovice, Theodosia…), and thus the characteristics and datums identified at Tré Maroua are key for correlation and, in general, they typify the J/K boundary interval in Tethys and connected seas
Źródło:
Volumina Jurassica; 2020, 18, 2; 121-160
1896-7876
1731-3708
Pojawia się w:
Volumina Jurassica
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:
A new type of slumping-induced soft-sediment deformation structure: the envelope structure
Autorzy:
Byun, Uk Hwan
van Loon, A. J. (Tom)
Kwon, Yi Kyun
Ko, Kyoungtae
Powiązania:
https://bibliotekanauki.pl/articles/950457.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
Gyeokpori Formation
Cretaceous
lacustrine environment
slumping
conglomerate
kreda
środowisko jeziorne
opadanie
konglomerat
Opis:
The sediments of the Cretaceous Gyeokpori Formation in south-western South Korea accumulated in a lake in which mainly siliciclastic rocks were deposited, with some interbedded volcaniclastics. The nearby volcanic activity resulted in unstable lake margins inducing a dominance of gravity-flow deposits. The high sedimentation rate facilitated soft-sediment deformation on the sloping margin. The deposition of numerous gravity-flow deposits resulted in a vertically heterolithic stratification. The slumps are composed of different lithologies, which is expressed in different types of deformation due to the difference in cohesion between sandy and mussy layers within the slumps. Coarser-grained (cohesionless) slumps tend to show more chaotic deformation of their lamination or layering. The difference in slumping behaviour of the cohesive and non-cohesive examples is explained and modelled. A unique soft-sediment deformation structure is recognized. This structure has not been described before, and we call it ‘envelope structure’. It consists of a conglomerate mass that has become entirely embedded in fine-grained sediment because slope failure took place and the fine-grained material slumped down with the conglomerate ‘at its back’. The cohesive laminated mudstone formed locally slump folds that embedded the non-cohesive overlying conglomerate unit, possibly partly due to the bulldozing effect of the latter. This structure presumably can develop when the density contrast with the underlying and overlying deposits is exceptionally high. The envelope structure should be regarded as a special – and rare – type of a slumping-induced deformation structure.
Źródło:
Geologos; 2019, 25, 2; 111-124
1426-8981
2080-6574
Pojawia się w:
Geologos
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hydro-chemical and microbiological characterization of Lower Cretaceous waters in a semi-arid zone Beni-Ounif syncline, South-West of Algeria
Hydrochemiczna i mikrobiologiczna charakterystyka wód dolnej kredy w półsuchej strefie synkliny Beni-Ounif w południowozachodniej Algierii
Autorzy:
Merzougui, Fatima Zahra
Makhloufi, Ahmed
Merzougui, Touhami
Powiązania:
https://bibliotekanauki.pl/articles/292610.pdf
Data publikacji:
2019
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
Beni-Ounif
groundwater
hierarchical cluster analysis (HCA)
hydro-chemical characterization
Lower Cretaceous
microbiological characterization
principal component analysis (PCA)
water quality
analiza składowych głównych (PCA)
charakterystyka hydrochemiczna
charakterystyka mikrobiologiczna
dolna kreda
hierarchiczna analiza skupień (HCA)
jakość wody
wody gruntowe
Opis:
The article analyses the water quality of the Lower Cretaceous aquifer in the Beni-Ounif syncline. To this end, 42 samples were taken for physico-chemical analysis and 28 for microbiological analysis in March, May and October 2017 from 14 sampling points. The results of physico-chemical analysis were processed by multi-variety statistical analysis methods: principal component analysis (PCA) and hierarchical cluster analysis (HCA) coupled to hydro chemical methods: Piper diagram. The PCA allowed us to explore the connections between physico-chemical parameters and similarities between samples and to identify the most appropriate physico-chemical elements to describe water quality. The HCA allowed us to classify the sampling points according to the similarity between them and thus reduce them for the next follow-up analysis. Waters of the syncline are characterized by medium to low mineralization (320 < EC < 7600 μS∙cm–1 and 200 < RS < 4020 mg∙dm–3) and hardness of between 22 and 123°f. Only 19% of the samples show NO3 concentrations exceeding the Algerian standards. Microbiologically, the study reports the presence of bacteria: coliforms (<8 CFU∙0.1 dm–3), Streptococcus D (<1100 CFU∙0.1 dm–3), Clostridium sulphito-reducer of vegetative form (<90 CFU∙0.02 dm–3) and sporulate (<4 CFU∙0.02 dm–3), total aerobic mesophilic flora at 22°C (<462 CFU∙0.001 dm–3) and at 37°C (<403 CFU∙0.001 dm–3). It must be noted that no presence of thermo-tolerant coliforms is observed.
W artykule przedstawiono wyniki analizy jakości wody z poziomu wodonośnego dolnej kredy w synklinie Beni-Ounif. W tym celu pobrano 42 próbki wody do analiz fizycznych i chemicznych oraz 28 próbek do analiz mikrobiologicznych z 14 stanowisk w marcu, maju i październiku 2017 r. Wyniki analiz fizycznych i chemicznych przetworzono za pomocą wieloczynnikowych metod statystycznych: analizy czynników głównych (PCA) i hierarchicznej analizy skupień (HCA) połączonej z metodami hydrochemicznymi, z diagramem Pipera. Analiza PCA umożliwiła zbadanie powiązań między parametrami fizycznymi i chemicznymi oraz podobieństwa między próbkami, a także identyfikację parametrów najbardziej odpowiednich do opisu jakości wody. Wykorzystując HCA, sklasyfikowano stanowiska według ich wzajemnego podobieństwa oraz zredukowano ich liczbę do przyszłych analiz. Wody synkliny charakteryzowały się małą do średniej mineralizacją (320 < EC < 7600 μS∙cm–1 i 200 < RS < 4020 mg∙dm–3) i twardością między 22 i 123°f. Tylko 19% próbek wykazywało stężenie azotanów przekraczające algierskie normy. W badanych wodach stwierdzono obecność bakterii z grupy Coli (<8 jtk∙(0,1 dm3)–1), Streptococcus D (<1100 jtk∙(0,1 dm3)–1), wegetatywnych form (<90 jtk∙(0,02 dm3)–1) i przetrwalników (<4 jtk∙(0,02 dm3)–1) Clostridium oraz całkowitej mezofilnej flory aerobowej w temperaturze 22°C (<462 jtk∙(0,001 dm3)–1) i 37°C (<403 jtk∙(0,001 dm3)–1). Należy dodać, że nie stwierdzono obecności termoodpornych bakterii z grupy Coli.
Źródło:
Journal of Water and Land Development; 2019, 40; 67-80
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł

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