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Andrew S Gale - One of the best experts on this subject based on the ideXlab platform.
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roveacrinidae crinoidea articulata from the cenomanian and Turonian of north africa agadir basin and anti atlas morocco and central tunisia biostratigraphy and taxonomy
Acta Geologica Polonica, 2020Co-Authors: Andrew S GaleAbstract: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.
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Turonian ammonites from northwestern aquitaine france
Cretaceous Research, 2016Co-Authors: James W Kennedy, Andrew S GaleAbstract:Abstract The position of the Cenomanian-Turonian boundary is established for the first time in Charente-Maritime, northwestern Aquitaine (France), on the basis of ammonite occurrences and the δ13C isotope curve, corresponding to Oceanic Anoxic Event 2, that straddles the boundary. The earliest Turonian ammonites recognised are a monospecific occurrence of the early early Turonian pseudotissotiine Bageites bakui Zaborski, 1998, previously known only from northern Nigeria. Newly collected material and well-preserved specimens from existing collections supplement previous records, and include species of Placenticeras, Morrowites, Kamerunoceras, Romaniceras (Romaniceras), Spathites (Jeanrogericeras), Mammites, Fagesia, Neoptychites, Choffaticeras (Leoniceras), Collignoniceras and Lecointriceras. These confirm the presence of the upper lower Turonian nodosoides Zone and the lower middle Turonian turoniense and kallesi zones/subzones of authors.
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carbon and oxygen isotope stratigraphy of the english chalk and italian scaglia and its palaeoclimatic significance
Geological Magazine, 1994Co-Authors: Hugh C Jenkyns, Andrew S Gale, R M CorfieldAbstract:A detailed carbon- and oxygen-isotope stratigraphy has been generated from Upper Cretaceous coastal Chalk sections in southern England (East Kent; Culver Cliff, Isle of Wight; Eastbourne and Seaford Head, Sussex; Norfolk Coast) and the British Geological Survey (BGS) Trunch borehole, Norfolk. Data are also presented from a section through the Scaglia facies exposed near Gubbio, Italian Apennines. Wherever possible the sampling interval has been one metre or less. Both the Chalk and Scaglia carbon-isotopic curves show minor positive excursions in the mid-Cenomanian, mid- and high Turonian, basal Coniacian and highest Santonian–lowest Campanian; there is a negative excursion high in the Campanian in Chalk sections that span that interval. The well-documented Cenomanian–Turonian boundary ‘spike’ is also well displayed, as is a broad positive excursion centred on the upper Coniacian. A number of these positive excursions correlate with records of organic-carbon-rich deposition in the Atlantic Ocean and elsewhere. The remarkable similarity in the carbon-isotope curves from England and Italy enables cross-referencing of macrofossil and microfossil zones and pinpoints considerable discrepancy in the relative positions of the Turonian, Coniacian and Santonian stages. The oxygen-isotope values of the various Chalk sections, although showing different absolute values that are presumably diagenesis-dependent, show nonetheless a consistent trend. The East Kent section, which is very poorly lithified, indicates a warming up to the Cenomanian–Turonian boundary interval, then cooling thereafter. Regional organic-carbon burial, documented for this period, is credited with causing drawdown of CO 2 and initiating climatic deterioration (inverse greenhouse effect). Data from other parts of the world are consistent with the hypothesis that the Cenomanian–Turonian temperature optimum was a global phenomenon and that this interval represents a major turning point in the climatic history of the earth.
Ireneusz Walaszczyk - One of the best experts on this subject based on the ideXlab platform.
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organic walled dinoflagellate cyst records from a prospective Turonian coniacian upper cretaceous gssp slupia nadbrzezna poland
Cretaceous Research, 2016Co-Authors: Kate Olde, Martin A Pearce, Ian Jarvis, Ireneusz Walaszczyk, Bruce A TocherAbstract:Abstract A river section at Slupia Nadbrzezna, central Poland, has been proposed as a candidate Turonian – Coniacian (Cretaceous) GSSP, in combination with the Salzgitter-Salder quarry section of Lower Saxony, Germany. Results of a high-resolution (25 cm) palynological study of the boundary interval in the Slupia Nadbrzezna section are presented. Terrestrial palynomorphs are rare; marine organic-walled dinoflagellate cysts dominate the palynological assemblage. The dinoflagellate cyst assemblage has a low species richness (5–11 per sample; total of 18 species recorded) and diversity (Shannon index H = 0.8–1.4), dominated by four taxa: Circulodinium distinctum subsp. distinctum; Oligosphaeridium complex; Spiniferites ramosus subsp. ramosus; Surculosphaeridium longifurcatum. Declining proportions of O. complex and S. ramosus subsp. ramosus characterise the uppermost Turonian, with an increased dominance of S. longifurcatum in the lower Coniacian. The Turonian – Coniacian boundary interval includes an acme of C. distinctum subsp. distinctum in the upper Mytiloides scupini Zone, a dinoflagellate cyst abundance maximum in the Cremnoceramus walterdorfensis walterdorfensis Zone, and the highest occurrence of Senoniasphaera turonica in the basal Coniacian lower Cremnoceramus deformis erectus Zone. Most previously reported Turonian – Coniacian boundary dinoflagellate cyst marker species are absent; a shallow-water oligotrophic epicontinental depositional setting, remote from terrestrial influence, likely limited species diversity and excluded many taxa of biostratigraphic value.
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inoceramid foraminiferal succession of the Turonian and coniacian upper cretaceous of the briansk region central european russia
Acta Geologica Polonica, 2004Co-Authors: Ireneusz Walaszczyk, Alexander G OlferievAbstract:An integrated inoceramid-foraminiferal zonation for the topmost Turonian and Lower Coniacian near Briansk, SW of Moscow is presented. The inoceramid fauna enables the application of the refined zonal scheme currently applied in central and western Europe. Three zones based on benthic foraminifera,.the Gavelinella moniliformis , Ataxophragmium nautiloides and Stensioeina granulata granulata zones; and three zones based on planktonic foraminifera, the Whiteinella archaeocretacea , Marginotruncana pseudolinneiana and Marginotruncana renzi zones, are distinguished. The Turonian/ Coniacian boundary, defined by the first appearance of the inoceramid Cremnoceramus deformis erectus (MEEK, 1877), falls within the basal part of the Stensioeina granulata granulata Zone and the basal part of Marginotruncana renzi Zone. In foraminiferal terms the Turonian/Coniacian boundary interval is marked additionally by a sudden, short-lived increase in the plankton/benthos ratio, caused primarily by more abundant shallow-water morphotypes.
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biogeographical and stratigraphical significance of the latest Turonian and early coniacian inoceramid ammonite succession of the manasoa section on the onilahy river south west madagascar
Cretaceous Research, 2004Co-Authors: Ireneusz Walaszczyk, Ryszard Marcinowski, T Praszkier, K Dembicz, M BienkowskaAbstract:Recent, bed-by-bed fossil collections from Manasoa on the Onilahy River, south-west Madagascar, reveal the stratigraphical succession of the inoceramid and ammonite faunas of the topmost Turonian through Lower and possibly lower Middle Coniacian of the area. Six successive interval inoceramid zones are recognised; from bottom upward these are zones of Tethyoceramus modestoides, Tethyoceramus madagascariensis, Tethyoceramus basseae, Tethyoceramus ernsti, Inoceramus? nukeus, and Inoceramus sp. aff. pacificus. The T. modestoides Zone lies within the Turonian. The base of the T. madagascariensis Zone marks the base of the Coniacian; all higher zones also lie within the Coniacian. The succession identified correlates well with other areas of the Southern Hemisphere and, to a lesser degree, with the Euramerican succession. The inoceramid faunas of the topmost Turonian through lower Coniacian of Madagascar are very similar to those of Zululand and are closely related to other Southern Hemisphere faunas. The Madagascan faunas are, however, clearly distinct from Euramerican faunas. The rich ammonite assemblage of the Manasoa section is dominated by endemic species characteristic of the Malgascan province, with only few forms known from Japan, Alaska and Europe. All of the ammonites represent the Barroisiceras onilahyense-Kossmaticeras (K.) theobaldianum Zone, which is shown to correspond to possibly topmost Turonian and Lower Coniacian. Taxonomic descriptions of the inoceramid species are provided, with range data and photographic documentation.
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mid Turonian to coniacian changes of sea level around dallas texas
Cretaceous Research, 2004Co-Authors: Jake M Hancock, Ireneusz WalaszczykAbstract:Abstract Improved dating by ammonites and inoceramids of the upper part of the Eagle Ford Shales (Middle and Upper Turonian) and the lower part of the Austin Chalk (top Turonian to Coniacian) in the Dallas area has given more accurate timing of sea-level changes. The broad rise in sea level from the Turonian into the Coniacian was a Texan tectonic effect. Individual regressive troughs, in cycles of the order of 100 kyr to 1 myr, seem to be a mainly eustatic effect. The pattern is very different from that over the San Marcos Arch in central Texas.
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pueblo colorado usa candidate global boundary stratotype section and point for the base of the Turonian stage of the cretaceous and for the base of the middle Turonian substage with a revision of the inoceramidae bivalvia
Acta Geologica Polonica, 2000Co-Authors: W J Kennedy, Ireneusz Walaszczyk, William A. CobbanAbstract:An updated account of the candidate Global Boundary Stratotype Section and Point for the base of the Turonian Stage and the base of the Middle Turonian Substage in the Bridge Creek Member of the Greenhorn Limestone exposed in the Rock Creek Anticline west of Pueblo, Colorado is provided. Key ammonite distributions are revised and marker species illustrated. A taxonomic revision of the uppermost Cenomanian to lower Middle Turonian bivalve family Inoceramidae provides, for the first time, an adequately documented detailed zonation for the interval in the form of five successive partial range zones based on species of the genus Mytiloides . These are successive zones of M. hattini ELDER (uppermost Cenomanian), M. puebloensis n.sp., M. kossmati (HEINZ), M. mytiloides (MANTELL) (all Lower Turonian) and M. subhercynicus (SEITZ) (lower Middle Turonian). The base of the Turonian, defined by the first appearance of the ammonite Watinoceras devonense WRIGHT & KENNEDY at the base of bed 86 of the Bridge Creek Member corresponds to the first occurrence of Mytiloides puebloensis , and the base of the puebloensis Zone. The base of the Middle Turonian, defined by the first occurrence of the ammonite Collignoniceras woollgari (MANTELL) in bed 120 of the Bridge Creek Member is just below the first occurrence of M. subhercynicus in bed 121, and the base of the subhercynicus Zone.
Matrion Bertrand - One of the best experts on this subject based on the ideXlab platform.
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Identification d'un biohorizon d'ammonites à Romaniceras (Romaniceras) marigniacum sp. nov. (Turonien moyen) à la base du Tuffeau Jaune de Touraine (France)
'INIST-CNRS', 2020Co-Authors: Amédro Francis, Robaszynski Francis, Châtelier Hervé, Ferchaud Patrice, Matrion BertrandAbstract:International audienceIn the south of the Paris Basin, along the Loire and Cher valleys, the Tuffeau Jaune de Touraine Formation was traditionally attributed to the Late Turonian by the presence of rare Romaniceras deverianum (Orbigny, 1841). Moreover, the several metres of tempestites at the base of the formation never yielded ammonites. Today, in southern Touraine, more than 150 ammonites were collected from the base of the Tuffeau Jaune de Touraine and in the highest part of the underlying Tuffeau de Bourré bring new significant data: the lower part of the Tuffeau Jaune de Touraine remain in the Romaniceras ornatissimum zone, Middle Turonian in age (Tm 3). Furthermore, the discovery in that biohorizon of the new species Romaniceras (R.) marigniacum Amédro & Châtelier sp. nov. is indicative of the highest part of the R. ornatissimum zone (high Tm3). Other species are associated to the R. marigniacum biohorizon as: Romaniceras (Yubariceras) ornatissimum (Stoliczka, 1864), Masiaposites cf. kennedyi Amédro & Devalque, 2014, Collignoniceras woollgari regulare (Haas, 1946), C. turoniense (Sornay, 1951) and Collignoniceras vigennum Amédro & Châtelier sp. nov.With regard to the top of the Tuffeau de Bourré Formation, it yielded about fifty specimens of ammonites but the assemblage is different to that found in the type locality of Bourré-Montrichard in the Cher valley. The material collected near the Vienne and Creuse junction includes : Lewesiceras peramplum (Mantell, 1822), Romaniceras (Y.) ornatissimum (Stoliczka, 1864), Collignoniceras woollgari regulare (Haas, 1946), C. canthus (Orbigny, 1856) and C. turoniense (Sornay, 1951). The species Collignoniceras papale (Orbigny, 1841), which represents one third of the Bourré collection is apparently absent whereas three new species belonging to the same genus are identified as : C. hourqueigi Amédro & Châtelier sp. nov., C. badilleti Amédro & Châtelier sp. nov. and Collignoniceras sp. A.Dans le sud du Bassin de Paris, le long des vallées de la Loire et du Cher, le Tuffeau Jaune de Touraine a été traditionnellement daté du Turonien supérieur par la présence de très rares Romaniceras deverianum (Orbigny, 1841). Toutefois, les quelques mètres de tempestites à la base de la formation n'ont jamais livré d'ammonites. Aujourd'hui, juste au sud du Turonien stratotypique, en Touraine méridionale, la récolte de plus de 150 ammonites à la base du Tuffeau Jaune de Touraine ainsi que dans le sommet du Tuffeau de Bourré sous-jacent apporte des précisions significatives sur l'âge des formations. En réalité, les premiers mètres du Tuffeau Jaune de Touraine appartiennent encore à la zone à Romaniceras ornatissimum (Tm 3) datant le Turonien moyen. La découverte dans cet intervalle de Romaniceras (Yubariceras) ornatissimum (Stoliczka, 1864) associé à la nouvelle espèce Romaniceras (R.) marigniacum Amédro & Châtelier sp. nov. indique qu'on se trouve dans la partie élevée de la zone à R. ornatissimum. D'autres espèces sont présentes dans ce biohorizon : outre Romaniceras (R.) marigniacum et Romaniceras (Yubariceras) ornatissimum, on trouve Masiaposites cf. kennedyi Amédro & Devalque, 2014, Collignoniceras woollgari regulare (Haas, 1946), C. turoniense (Sornay, 1951) et Collignoniceras vigennum Amédro & Châtelier sp. nov.Le sommet du Tuffeau de Bourré a quant à lui livré une cinquantaine d'ammonites avec une association légèrement différente de celle connue dans la localité type de Bourré-Montrichard dans la vallée du Cher. Le matériel récolté près de la confluence Vienne-Creuse comprend : Lewesiceras peramplum (Mantell, 1822), Romaniceras (Y.) ornatissimum (Stoliczka, 1864), Collignoniceras woollgari regulare (Haas, 1946), C. canthus (Orbigny, 1856) et C. turoniense (Sornay, 1951). L'espèce Collignoniceras papale (Orbigny, 1841), qui représente un tiers des récoltes à Bourré, est apparemment absente, tandis que trois nouvelles espèces du même genre sont identifiées : C. hourqueigi Amédro & Châtelier sp. nov., C. badilleti Amédro & Châtelier sp. nov. et Collignoniceras sp. A
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Identification of a Romaniceras (Romaniceras) marigniacum sp. nov. ammonite biohorizon (Middle Turonian) at the base of the Tuffeau Jaune de Touraine (France)
'INIST-CNRS', 2020Co-Authors: Amédro Francis, Robaszynski Francis, Châtelier Hervé, Ferchaud Patrice, Matrion BertrandAbstract:Dans le sud du Bassin de Paris, le long des vallées de la Loire et du Cher, le Tuffeau Jaune de Touraine a été traditionnellement daté du Turonien supérieur par la présence de très rares Romaniceras deverianum (Orbigny, 1841). Toutefois, les quelques mètres de tempestites à la base de la formation n'ont jamais livré d'ammonites. Aujourd'hui, juste au sud du Turonien stratotypique, en Touraine méridionale, la récolte de plus de 150 ammonites à la base du Tuffeau Jaune de Touraine ainsi que dans le sommet du Tuffeau de Bourré sous-jacent apporte des précisions significatives sur l'âge des formations. En réalité, les premiers mètres du Tuffeau Jaune de Touraine appartiennent encore à la zone à Romaniceras ornatissimum (Tm 3) datant le Turonien moyen. La découverte dans cet intervalle de Romaniceras (Yubariceras) ornatissimum (Stoliczka, 1864) associé à la nouvelle espèce Romaniceras (R.) marigniacum Amédro & Châtelier sp. nov. indique qu'on se trouve dans la partie élevée de la zone à R. ornatissimum. D'autres espèces sont présentes dans ce biohorizon : outre Romaniceras (R.) marigniacum et Romaniceras (Yubariceras) ornatissimum, on trouve Masiaposites cf. kennedyi Amédro & Devalque, 2014, Collignoniceras woollgari regulare (Haas, 1946), C. turoniense (Sornay, 1951) et Collignoniceras vigennum Amédro & Châtelier sp. nov. Le sommet du Tuffeau de Bourré a quant à lui livré une cinquantaine d'ammonites avec une association légèrement différente de celle connue dans la localité type de Bourré-Montrichard dans la vallée du Cher. Le matériel récolté près de la confluence Vienne-Creuse comprend : Lewesiceras peramplum (Mantell, 1822), Romaniceras (Y.) ornatissimum (Stoliczka, 1864), Collignoniceras woollgari regulare (Haas, 1946), C. canthus (Orbigny, 1856) et C. turoniense (Sornay, 1951). L'espèce Collignoniceras papale (Orbigny, 1841), qui représente un tiers des récoltes à Bourré, est apparemment absente, tandis que trois nouvelles espèces du même genre sontIn the south of the Paris Basin, along the Loire and Cher valleys, the Tuffeau Jaune de Touraine Formation was traditionally attributed to the Late Turonian by the presence of rare Romaniceras deverianum (Orbigny, 1841). Moreover, the several metres of tempestites at the base of the formation never yielded ammonites. Today, in southern Touraine, more than 150 ammonites were collected from the base of the Tuffeau Jaune de Touraine and in the highest part of the underlying Tuffeau de Bourré bring new significant data: the lower part of the Tuffeau Jaune de Touraine remain in the Romaniceras ornatissimum zone, Middle Turonian in age (Tm 3). Furthermore, the discovery in that biohorizon of the new species Romaniceras (R.) marigniacum Amédro & Châtelier sp. nov. is indicative of the highest part of the R. ornatissimum zone (high Tm3). Other species are associated to the R. marigniacum biohorizon as: Romaniceras (Yubariceras) ornatissimum (Stoliczka, 1864), Masiaposites cf. kennedyi Amédro & Devalque, 2014, Collignoniceras woollgari regulare (Haas, 1946), C. turoniense (Sornay, 1951) and Collignoniceras vigennum Amédro & Châtelier sp. nov. With regard to the top of the Tuffeau de Bourré Formation, it yielded about fifty specimens of ammonites but the assemblage is different to that found in the type locality of Bourré-Montrichard in the Cher valley. The material collected near the Vienne and Creuse junction includes : Lewesiceras peramplum (Mantell, 1822), Romaniceras (Y.) ornatissimum (Stoliczka, 1864), Collignoniceras woollgari regulare (Haas, 1946), C. canthus (Orbigny, 1856) and C. turoniense (Sornay, 1951). The species Collignoniceras papale (Orbigny, 1841), which represents one third of the Bourré collection is apparently absent whereas three new species belonging to the same genus are identified as : C. hourqueigi Amédro & Châtelier sp. nov., C. badilleti Amédro & Châtelier sp. nov. and Collignoniceras sp. A
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Identification d'un biohorizon d'ammonites à Romaniceras (Romaniceras) marigniacum sp. nov. (Turonien moyen) à la base du Tuffeau Jaune de Touraine (France).
'INIST-CNRS', 2020Co-Authors: Amédro Francis, Robaszynski Francis, Châtelier Hervé, Ferchaud Patrice, Matrion BertrandAbstract:53 pagesInternational audienceIn the south of the Paris Basin, along the Loire and Cher valleys, the Tuffeau Jaune de Touraine Formation was traditionally attributed to the Late Turonian by the presence of rare Romaniceras deverianum (Orbigny, 1841). Moreover, the several metres of tempestites at the base of the formation never yielded ammonites. Today, in southern Touraine, more than 150 ammonites were collected from the base of the Tuffeau Jaune de Touraine and in the highest part of the underlying Tuffeau de Bourré bring new significant data: the lower part of the Tuffeau Jaune de Touraine remain in the Romaniceras ornatissimum zone, Middle Turonian in age (Tm 3). Furthermore, the discovery in that biohorizon of the new species Romaniceras (R.) marigniacum Amédro & Châtelier sp. nov. is indicative of the highest part of the R. ornatissimum zone (high Tm3). Other species are associated to the R. marigniacum biohorizon as: Romaniceras (Yubariceras) ornatissimum (Stoliczka, 1864), Masiaposites cf. kennedyi Amédro & Devalque, 2014, Collignoniceras woollgari regulare (Haas, 1946), C. turoniense (Sornay, 1951) and Collignoniceras vigennum Amédro & Châtelier sp. nov.With regard to the top of the Tuffeau de Bourré Formation, it yielded about fifty specimens of ammonites but the assemblage is different to that found in the type locality of Bourré-Montrichard in the Cher valley. The material collected near the Vienne and Creuse junction includes : Lewesiceras peramplum (Mantell, 1822), Romaniceras (Y.) ornatissimum (Stoliczka, 1864), Collignoniceras woollgari regulare (Haas, 1946), C. canthus (Orbigny, 1856) and C. turoniense (Sornay, 1951). The species Collignoniceras papale (Orbigny, 1841), which represents one third of the Bourré collection is apparently absent whereas three new species belonging to the same genus are identified as : C. hourqueigi Amédro & Châtelier sp. nov., C. badilleti Amédro & Châtelier sp. nov. and Collignoniceras sp. A.Dans le sud du Bassin de Paris, le long des vallées de la Loire et du Cher, le Tuffeau Jaune de Touraine a été traditionnellement daté du Turonien supérieur par la présence de très rares Romaniceras deverianum (Orbigny, 1841). Toutefois, les quelques mètres de tempestites à la base de la formation n'ont jamais livré d'ammonites. Aujourd'hui, juste au sud du Turonien stratotypique, en Touraine méridionale, la récolte de plus de 150 ammonites à la base du Tuffeau Jaune de Touraine ainsi que dans le sommet du Tuffeau de Bourré sous-jacent apporte des précisions significatives sur l'âge des formations. En réalité, les premiers mètres du Tuffeau Jaune de Touraine appartiennent encore à la zone à Romaniceras ornatissimum (Tm 3) datant le Turonien moyen. La découverte dans cet intervalle de Romaniceras (Yubariceras) ornatissimum (Stoliczka, 1864) associé à la nouvelle espèce Romaniceras (R.) marigniacum Amédro & Châtelier sp. nov. indique qu'on se trouve dans la partie élevée de la zone à R. ornatissimum. D'autres espèces sont présentes dans ce biohorizon : outre Romaniceras (R.) marigniacum et Romaniceras (Yubariceras) ornatissimum, on trouve Masiaposites cf. kennedyi Amédro & Devalque, 2014, Collignoniceras woollgari regulare (Haas, 1946), C. turoniense (Sornay, 1951) et Collignoniceras vigennum Amédro & Châtelier sp. nov.Le sommet du Tuffeau de Bourré a quant à lui livré une cinquantaine d'ammonites avec une association légèrement différente de celle connue dans la localité type de Bourré-Montrichard dans la vallée du Cher. Le matériel récolté près de la confluence Vienne-Creuse comprend : Lewesiceras peramplum (Mantell, 1822), Romaniceras (Y.) ornatissimum (Stoliczka, 1864), Collignoniceras woollgari regulare (Haas, 1946), C. canthus (Orbigny, 1856) et C. turoniense (Sornay, 1951). L'espèce Collignoniceras papale (Orbigny, 1841), qui représente un tiers des récoltes à Bourré, est apparemment absente, tandis que trois nouvelles espèces du même genre sont identifiées : C. hourqueigi Amédro & Châtelier sp. nov., C. badilleti Amédro & Châtelier sp. nov. et Collignoniceras sp. A
Emad Nagm - One of the best experts on this subject based on the ideXlab platform.
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stratigraphic significance of rapid faunal change across the cenomanian Turonian boundary in the eastern desert egypt
Cretaceous Research, 2015Co-Authors: Emad NagmAbstract:Abstract A significant and rapid faunal change across the Cenomanian–Turonian boundary in the Eastern Desert of Egypt has been recognized by reconstructing the stratigraphic ranges of macroinvertebrates within the upper Cenomanian–lower Turonian Galala and Abu Qada formations. The faunal change initiated with a considerable loss of taxa during the late Cenomanian at the top of the Neolobites vibrayeanus ammonite zone, coinciding with sequence boundary SB Ce 5, ∼400 ka before the Cenomanian–Turonian boundary (93.9 Ma). Only 10% of the taxa that existed during the late Cenomanian have been recorded from lower Turonian strata. The changes in the macroinvertebrate faunas continued across the Cenomanian–Turonian boundary and new faunal associations evolved after the earliest Turonian Vascoceras proprium ammonite zone of (∼200 ka after the Cenomanian–Turonian boundary). Therefore, the crisis that caused this faunal change around the Cenomanian–Turonian boundary over approximately 600 ka. The timing of the macrofaunal change recognized in the study area completely overlaps with the well-known Oceanic Anoxic Event (OAE) 2 and most probably it is one of the effects of the major environmental perturbations (critical warming, high atmospheric CO 2 concentration, and ocean water acidification) associated with this event. In addition, the sequence-stratigraphic analysis shows strong correlation exists between pattern of first and last occurrences of macroinvertebrate faunas and sea-level changes. Therefore, the oceanographic changes (rapid sea-level rise) may have also contributed to the Cenomanian–Turonian faunal change in the study area.
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stable isotope stratigraphy of the cenomanian Turonian upper cretaceous boundary event ctbe in wadi qena eastern desert egypt
Journal of African Earth Sciences, 2014Co-Authors: Emad Nagm, Gamal Elqot, Markus WilmsenAbstract:A high-resolution δ13C isotope record from Cenomanian–Turonian boundary interval of shallow marine successions in Egypt is presented. The δ13C curves show the typical features of the globally documented Cenomanian–Turonian positive excursion, including three of the main positive isotope peaks defining the Cenomanian–Turonian Boundary Event (CTBE). Based on high-resolution ammonite biostratigraphy, the CTBE started in the study area above the Late Cenomanian Neolobites vibrayeanus Zone within the Galala Formation, directly above the global sequence boundary Cenomanian 5 (SB Ce 5). A stratigraphic gap at that level cuts out the lower a-peak of the CTBE. The Cenomanian–Turonian boundary is located within the upper part of the positive excursion between carbon excursion peaks c and d, coinciding with the boundary between the Late Cenomanian Vascoceras cauvini and the Early Turonian Vascoceratid zones. The CTBE ended up-section of peak d, at the base of the Choffaticeras spp. Zone. The amplitude of the positive δ13C excursion in Egypt is very high (reaching 6.5‰ vs. V-PDB) and largely matches curves of European standard sections and others localities from different basins. Furthermore, the Lower Turonian Holywell Isotope Event, an important marker within the lowermost Turonian, has tentatively been recognized. The positive carbon stable isotope curves presented herein represent the outreach of the oceanic anoxic event (OAE) 2 in shallow-water nearshore sequences.
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late cenomanian Turonian cretaceous ammonites from wadi qena central eastern desert egypt taxonomy biostratigraphy and palaeobiogeographic implications
Acta Geologica Polonica, 2012Co-Authors: Emad Nagm, Markus WilmsenAbstract:In Egypt, marine Upper Cenomanian–Turonian strata are well exposed in the Eastern Desert. The southernmost outcrops are located in the central part of Wadi Qena, where the lower Upper Cretaceous is represented by the fossiliferous Galala and Umm Omeiyid formations. From these strata, numerous ammonites have been collected bed-by-bed and 13 taxa have been identified, which are systematically described herein. Four of them ( Euomphaloceras costatum , Vascoceras globosum globosum , Thomasites gongilensis and Pseudotissotia nigeriensis ) are recorded from Egypt for the first time. The ammonite ranges are used for a biostratigraphic zonation of the lower Upper Cretaceous succession in the northern and central part of Wadi Qena: the Upper Cenomanian–Lower Turonian has been subdivided into five biozones (including a new upper Lower Turonian biozone based on the occurrence of Pseudotissotia nigeriensis ), and one biozone has been recognized in the Upper Turonian. Palaeobiogeographically, the ammonite assemblage has a Tethyan character. During the Early Turonian, influences of the Vascoceratid Province were predominant with strong affinities to typical Nigerian faunas. This shows the significance of faunal exchange between Egypt and Central and West Africa via the Trans-Saharan Seaway. Compared to contemporaneous ammonoid faunas from the northern part of the Eastern Desert, Boreal influences are much less obvious in Wadi Qena. Thus, the present study greatly enhances the knowledge of the Late Cretaceous palaeobiogeography and biostratigraphy of Egypt and adjacent areas.
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coilopoceras inflatum cobban and hook 1980 a united states western interior ammonite from the upper Turonian of the southern corbieres aude france
Acta Geologica Polonica, 2017Co-Authors: Patrice Melchior, Michel Bilotte, W J KennedyAbstract:A newly discovered ammonite faunule from the Padern region of the southern Corbieres in southern France includes representatives of typical northwest European Upper Turonian species Subprionocyclus cf. neptuni (Geinitz, 1850) and Lewesiceras cf. woodi Wright 1979, tethyan/ northwestern Pacific species Phyllopachyceras cf. ezoense (Yokoyama, 1890), Anagaudryceras involvulum (Stoliczka, 1865) and, Desmoceras ( Pseudouhligella ) sp., together with Coilopoceras inflatum Cobban and Hook, 1980, a species previously known only from New Mexico in the United States, where it is regarded as Middle Turonian. The faunule occurs above one with Romaniceras ( R .) mexicanum Jones, 1938 and Coilopoceras springeri Hyatt, 1903, also originally described from New Mexico and northern Mexico, and recently described from the Uchaux massif in Vaucluse in southern France. The records suggest that the base of the Upper Turonian may be drawn at different, higher level in the United States Western Interior than in Europe. The coming together of these mixed faunal elements may be a result of high sea levels, and changing oceanic circulation patterns.
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the ammonites reymenticoceras gen nov nodosoidesappelatus etayo serna 1979 benueites reymenti collignon 1976 and tolimacoceras gen nov colombianus etayo serna 1979 from the lower Turonian of tolima province colombia
Cretaceous Research, 2017Co-Authors: W J KennedyAbstract:Abstract An ammonite faunule from the lower Turonian of Tolima Province, Colombia is described. It is dated as late early Turonian on the basis of the presence of Benueites Reyment, 1954, plus two new genera: Reymenticoceras (Mammitinae) and Tolimacoceras (Vascoceratidae).
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Turonian ammonite faunas from the southern corbieres aude france
Acta Geologica Polonica, 2015Co-Authors: W J Kennedy, Michel Bilotte, Patrice MelchiorAbstract:The Turonian successions of the southern Corbieres comprise three transgressive-regressive cycles in which ammonites occur in three intervals. The lowest comes from the glauconitic basal transgressive unit of the first cycle, and comprises 21 species, including Kamerunoceras douvillei (Pervinquiere, 1907), Kamerunoceras turoniense (d’Orbigny, 1850), Spathites ( Jeanrogericeras ) revelerianus (Courtiller, 1860), Spathites ( Jeanrogericeras ) combesi (d’Orbigny, 1856), Mammites nodosoides (Schluter, 1871), Mammites powelli Kennedy, Wright and Hancock, 1987, Fagesia tevestensis (Peron, 1896), Neoptychites cephalotus (Coutiller, 1860), Thomasites rollandi (Thomas and Peron, 1889), Wrightoceras wallsi Reyment, 1954, and Choffaticeras ( Choffaticeras ) quaasi (Peron, 1904). This is a Lower Turonian assemblage referred to the Mammites nodosoides Zone, although the possibility that elements from the preceding Fagesia catinus Zone are also present cannot be excluded. The fauna from the transgressive glauconitic interval of the succeeding cycle comprises nine species, including Romaniceras ( Romaniceras ) mexicanum Jones, 1938, Romaniceras ( Yubariceras ) ornatissimum (Stoliczka, 1864), Pseudotissotia galliennei (d’Orbigny, 1850), Collignoniceras woollgari (Mantell, 1822) sensu lato, Coilopoceras springeri Hyatt, 1903, and Eubostrychoceras ( Eubostrychoceras ) saxonicum (Schluter, 1872). They indicate the Middle Turonian Romaniceras ( R .) mexicanum and R . ( Y .) ornatissimum zones. The highest fauna, from the Marnes superieurs de Saint-Louis of the Saint-Louis syncline, is: Subprionocyclus sp. juv., Prionocyclus sp. and Worthoceras cf. rochatianum (d’Orbigny, 1850). The Subprionocyclus are minute individuals that resemble S. bravaisianus (d’Orbigny, 1841), and suggest the presence of the lower Upper Turonian bravaisianus Zone.
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pueblo colorado usa candidate global boundary stratotype section and point for the base of the Turonian stage of the cretaceous and for the base of the middle Turonian substage with a revision of the inoceramidae bivalvia
Acta Geologica Polonica, 2000Co-Authors: W J Kennedy, Ireneusz Walaszczyk, William A. CobbanAbstract:An updated account of the candidate Global Boundary Stratotype Section and Point for the base of the Turonian Stage and the base of the Middle Turonian Substage in the Bridge Creek Member of the Greenhorn Limestone exposed in the Rock Creek Anticline west of Pueblo, Colorado is provided. Key ammonite distributions are revised and marker species illustrated. A taxonomic revision of the uppermost Cenomanian to lower Middle Turonian bivalve family Inoceramidae provides, for the first time, an adequately documented detailed zonation for the interval in the form of five successive partial range zones based on species of the genus Mytiloides . These are successive zones of M. hattini ELDER (uppermost Cenomanian), M. puebloensis n.sp., M. kossmati (HEINZ), M. mytiloides (MANTELL) (all Lower Turonian) and M. subhercynicus (SEITZ) (lower Middle Turonian). The base of the Turonian, defined by the first appearance of the ammonite Watinoceras devonense WRIGHT & KENNEDY at the base of bed 86 of the Bridge Creek Member corresponds to the first occurrence of Mytiloides puebloensis , and the base of the puebloensis Zone. The base of the Middle Turonian, defined by the first occurrence of the ammonite Collignoniceras woollgari (MANTELL) in bed 120 of the Bridge Creek Member is just below the first occurrence of M. subhercynicus in bed 121, and the base of the subhercynicus Zone.
