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Nicolas Thibault - One of the best experts on this subject based on the ideXlab platform.
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The Santonian-Campanian Boundary Event (SCBE) in boreal basins: new geochemical and mineralogical data from the Northern Chalk Province (East Yorkshire, UK).
Cretaceous Research, 2019Co-Authors: Matthieu Deville De Périère, Pierre Pellenard, Nicolas ThibaultAbstract:The Upper Cretaceous Flamborough Chalk Formation of the English Northern Chalk Province (Danes Dyke section, East Yorkshire, UK) has been sampled for isotope analyses to test for the expression of the positive carbon-isotope excursion defining the Santonian–Campanian Boundary Event (SCBE) in northern England, and to improve basin-scale correlations between the Boreal and Tethyan realms. Clay mineral investigations have been conducted in order to characterise potential variations in the detrital flux between the top of the Santonian and the base of the Campanian, and to test relationships with the SCBE. In the Flamborough Chalk and in other chalk sections, the Santonian/Campanian boundary is defined by the highest occurrence datum of the crinoid Marsupites. Carbon isotope results in this section indicate the presence of the negative Foreness Event in the upper Santonian, while the SCBE is characterised by a double positive excursion with peaks respectively named ‘a’ and ‘b’. The first peak of the SCBE (a) lies in the uppermost part of the Marsupites Zone and therefore belongs to the upper Santonian. Peak b of the SCBE is located above the highest occurrence of Marsupites and is thus partially included in the Uintacrinus anglicus Zone of the lower Campanian. The clay fraction (
Katharina Böhm - One of the best experts on this subject based on the ideXlab platform.
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the santonian campanian boundary and the end of the long cretaceous normal polarity chron isotope and plankton stratigraphy of a pelagic reference section in the nw tethys austria
Newsletters on Stratigraphy, 2018Co-Authors: Erik Wolfgring, Katharina Böhm, Susanne Gier, Benjamin Sames, Christoph Spötl, Jaume Dinaresturell, Friedrich PoppAbstract:The base of the Campanian still lacks a designated primary marker and a defined GSSP (Global Boundary Stratotype Section and Point). We present a Santonian–Campanian boundary section from the Postalm in the Northern Calcareous Alps of Austria as a possible reference section for the northwestern Tethys. Including nearby complementary Gosau Group sections, the stratigraphy for this time interval is based on palaeomagnetic and stable isotope data, planktonic foraminifera and calcareous nannoplankton bio-stratigraphy, and strontium isotope stratigraphy, together with published ammonite, crinoid and inoceramid data. The Postalm section shows a deepening trend from upper Santonian conglomerates and grey shelf marls to pelagic bathyal red marly limestones of mainly Campanian age. Palaeomagnetic data allow identifying the top of the Long Cretaceous Normal Polarity-Chron C34n and the following reversal in the lower part of the red marly limestones. A 1 m-thick interval of high magnetic susceptibility is present at the end of C34n. Two of the main suggested biomarkers to pinpoint the Santonian–Campanian boundary, i. e. the last occurrence of the planktonic foraminifer Dicarinella asymetrica and the first occurrence of the nannofossil Broinsonia parca parca, occur in close proximity above the reversal, which is suggested herein as the main marker event for the base of the Campanian. Strontium isotope stratigraphy indicates a value of 0.707534 (mean of four measurements at the boundary interval) for the base of the Campanian in the Postalm section. Both carbon and oxygen isotope values show a negative excursion just below the boundary. The positive Santonian–Campanian carbon isotope event starts probably just below the reversal but seems to be diagenetically distorted. This interval is considered to correspond to a short sea-level high in the late Santonian followed by a distinct lowstand at the Santonian–Campanian boundary.
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plankton biostratigraphy and magnetostratigraphy of the santonian campanian boundary interval in the mudurnu goynuk basin northwestern turkey
Cretaceous Research, 2017Co-Authors: Erik Wolfgring, Ismail Omer Yilmaz, Jaume Dinaresturell, Katharina BöhmAbstract:Abstract The Santonian–Campanian boundary interval close to the village of Goynuk in northwestern Turkey (Bolu province) was recorded and examined with respect to nannofossil and foraminiferal biostratigraphy, magnetic polarity and magnetic susceptibility. During the Late Cretaceous, the Mudurnu–Goynuk Basin was located on the Sakarya continent situated in the northwestern Tethyan Realm, north of the Neo-Tethys. The sections assessed for the present study comprise hemipelagic to pelagic deposits. Five localities were examined and a composite record spanning the Santonian–Campanian boundary was established. The stratigraphically older parts are characterised by uniform reddish limestone, while we frequently recorded shaly marls and marly limestones with recurrent tuff intercalations in the younger subsections. A biostratigraphic investigation of planktonic foraminifera and calcareous nannoplankton assemblages, together with magnetostratigraphy, provides a stratigraphic framework that allows to home in on the Santonian–Campanian boundary. Thus, biostratigraphic data suggest an age that ranges from the late Santonian Dicarinella asymetrica to the early Campanian Globotruncanita elevata planktonic foraminifera biozones, and calcareous nannofossil zones UC12–UC14 and CC16–CC18. The magnetostratigraphic assessment finds a palaeomagnetic reversal that can be recognised as the basal Campanian reversal C33r above polarity chron 34n, the Long Cretaceous Normal. Field magnetic susceptibility (MS) data show a distinct cyclic pattern in the lower Campanian. Sinusoidal patterns in the MS signature curve can presumably be interpreted as the 400 kyr orbital eccentricity cycle, and subsequent smaller-scale cycles of obliquity and precession can be identified even though volcanic activity impacted sedimentation. A sediment accumulation rate of 12 mm/kyr can be inferred for one of the sections.
Takuto Ando - One of the best experts on this subject based on the ideXlab platform.
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Establishment of Upper Cretaceous bio- and carbon isotope stratigraphy in the northwest Pacific Ocean and radiometric ages around the Albian/Cenomanian, Coniacian/Santonian and Santonian/Campanian boundaries
Newsletters on Stratigraphy, 2019Co-Authors: Reishi Takashima, Hiroshi Nishi, Toshiro Yamanaka, Yuji Orihashi, Yasuyuki Tsujino, Xavier Quidelleur, Keiichi Hayashi, Ken Sawada, Hideto Nakamura, Takuto AndoAbstract:The Yezo Group, exposed in Hokkaido, northern Japan, is one of the few strata that recorded Cretaceous paleo-oceanographic changes in the Pacific Ocean. Although the group yields abundant marine macro- and microfossils, sporadic occurrences of age-diagnostic species in several stratigraphic intervals has prevented high-resolution international biostratigraphic correlation. The proposed integrated bio- and carbon isotope stratigraphy of the Yezo Group, which is exposed in northwest Hokkaido, enables high-resolution international stratigraphic correlation spanning from Upper Albian to Lower Campanian. The correlation of the present study identifies the detailed stratigraphic horizons of the Albian/Cenomanian, Cenomanian/Turonian, Turonian/Coniacian, Coniacian/Santonian, and Santonian/Campanian boundaries, as well as the Late Cretaceous paleo-environmental events in the Yezo Group. The Yezo Group is also important in order to complement the chronometric age of the Cretaceous geologic time scale because the group includes numerous felsic tuffs. The U-Pb zircon ages of some of these tuffs, which are interbedded near the Albian/Cenomanian, Coniacian/Santonian and the Santonian/Campanian boundaries in the Yezo Group, are dated at 99.7±0.3 Ma (Quidelleur et al. 2011), 86.87±0.60/0.67 (internal/total error) Ma and 84.7±0.7/1.8 (internal/total error) Ma, respectively. These radiometric ages are consistent with the latest age model of the Cretaceous time scale.
Matthieu Deville De Périère - One of the best experts on this subject based on the ideXlab platform.
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The Santonian-Campanian Boundary Event (SCBE) in boreal basins: new geochemical and mineralogical data from the Northern Chalk Province (East Yorkshire, UK).
Cretaceous Research, 2019Co-Authors: Matthieu Deville De Périère, Pierre Pellenard, Nicolas ThibaultAbstract:The Upper Cretaceous Flamborough Chalk Formation of the English Northern Chalk Province (Danes Dyke section, East Yorkshire, UK) has been sampled for isotope analyses to test for the expression of the positive carbon-isotope excursion defining the Santonian–Campanian Boundary Event (SCBE) in northern England, and to improve basin-scale correlations between the Boreal and Tethyan realms. Clay mineral investigations have been conducted in order to characterise potential variations in the detrital flux between the top of the Santonian and the base of the Campanian, and to test relationships with the SCBE. In the Flamborough Chalk and in other chalk sections, the Santonian/Campanian boundary is defined by the highest occurrence datum of the crinoid Marsupites. Carbon isotope results in this section indicate the presence of the negative Foreness Event in the upper Santonian, while the SCBE is characterised by a double positive excursion with peaks respectively named ‘a’ and ‘b’. The first peak of the SCBE (a) lies in the uppermost part of the Marsupites Zone and therefore belongs to the upper Santonian. Peak b of the SCBE is located above the highest occurrence of Marsupites and is thus partially included in the Uintacrinus anglicus Zone of the lower Campanian. The clay fraction (
Chase Doran Brownstein - One of the best experts on this subject based on the ideXlab platform.
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strict_consensus.tre from Dinosaurs from the Santonian–Campanian Atlantic coastline substantiate phylogenetic signatures of vicariance in Cretaceous North America
2021Co-Authors: Chase Doran BrownsteinAbstract:During the Cretaceous, diversifications and turnovers affected terrestrial vertebrates experiencing the effects of global geographical change. However, the poor fossil record from the Middle Cretaceous has concealed how dinosaurs and other terrestrial vertebrates responded to these events. I describe two dinosaurs from the Santonian to Early Campanian of the obscure North American paleolandmass Appalachia. A revised look at a large, potentially novel theropod shows that it likely belongs to a new clade of tyrannosauroids solely from Appalachia. Another partial skeleton belongs to an early member of the Hadrosauridae, a highly successful clade of herbivorous dinosaurs. This skeleton is associated with the first perinate dinosaur specimens from the Atlantic Coastal Plain. The tyrannosauroid and hadrosaurid substantiate one of the only Late Santonian dinosaur faunas and help pinpoint the timing of important anatomical innovations in two widespread dinosaur lineages. The phylogenetic positions of the tyrannosauroid and hadrosaurid show Santonian Appalachian dinosaur faunas are surprisingly comparable to coeval Eurasian ones, and the presence of clades formed only by Appalachian dinosaur taxa establishes a degree of endemism in Appalachian dinosaur assemblages attributable to episodes of vicariance
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Supplementary Information (Text);Supplementary Data (Phylogenetic Matrices, Measurements, and Trees) from Dinosaurs from the Santonian–Campanian Atlantic coastline substantiate phylogenetic signatures of vicariance in Cretaceous North America
2021Co-Authors: Chase Doran BrownsteinAbstract:During the Cretaceous, diversifications and turnovers affected terrestrial vertebrates experiencing the effects of global geographical change. However, the poor fossil record from the Middle Cretaceous has concealed how dinosaurs and other terrestrial vertebrates responded to these events. I describe two dinosaurs from the Santonian to Early Campanian of the obscure North American paleolandmass Appalachia. A revised look at a large, potentially novel theropod shows that it likely belongs to a new clade of tyrannosauroids solely from Appalachia. Another partial skeleton belongs to an early member of the Hadrosauridae, a highly successful clade of herbivorous dinosaurs. This skeleton is associated with the first perinate dinosaur specimens from the Atlantic Coastal Plain. The tyrannosauroid and hadrosaurid substantiate one of the only Late Santonian dinosaur faunas and help pinpoint the timing of important anatomical innovations in two widespread dinosaur lineages. The phylogenetic positions of the tyrannosauroid and hadrosaurid show Santonian Appalachian dinosaur faunas are surprisingly comparable to coeval Eurasian ones, and the presence of clades formed only by Appalachian dinosaur taxa establishes a degree of endemism in Appalachian dinosaur assemblages attributable to episodes of vicariance
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Hadrosauridae.nex from Dinosaurs from the Santonian–Campanian Atlantic coastline substantiate phylogenetic signatures of vicariance in Cretaceous North America
2021Co-Authors: Chase Doran BrownsteinAbstract:During the Cretaceous, diversifications and turnovers affected terrestrial vertebrates experiencing the effects of global geographical change. However, the poor fossil record from the Middle Cretaceous has concealed how dinosaurs and other terrestrial vertebrates responded to these events. I describe two dinosaurs from the Santonian to Early Campanian of the obscure North American paleolandmass Appalachia. A revised look at a large, potentially novel theropod shows that it likely belongs to a new clade of tyrannosauroids solely from Appalachia. Another partial skeleton belongs to an early member of the Hadrosauridae, a highly successful clade of herbivorous dinosaurs. This skeleton is associated with the first perinate dinosaur specimens from the Atlantic Coastal Plain. The tyrannosauroid and hadrosaurid substantiate one of the only Late Santonian dinosaur faunas and help pinpoint the timing of important anatomical innovations in two widespread dinosaur lineages. The phylogenetic positions of the tyrannosauroid and hadrosaurid show Santonian Appalachian dinosaur faunas are surprisingly comparable to coeval Eurasian ones, and the presence of clades formed only by Appalachian dinosaur taxa establishes a degree of endemism in Appalachian dinosaur assemblages attributable to episodes of vicariance
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hadroboots.tre from Dinosaurs from the Santonian–Campanian Atlantic coastline substantiate phylogenetic signatures of vicariance in Cretaceous North America
2021Co-Authors: Chase Doran BrownsteinAbstract:During the Cretaceous, diversifications and turnovers affected terrestrial vertebrates experiencing the effects of global geographical change. However, the poor fossil record from the Middle Cretaceous has concealed how dinosaurs and other terrestrial vertebrates responded to these events. I describe two dinosaurs from the Santonian to Early Campanian of the obscure North American paleolandmass Appalachia. A revised look at a large, potentially novel theropod shows that it likely belongs to a new clade of tyrannosauroids solely from Appalachia. Another partial skeleton belongs to an early member of the Hadrosauridae, a highly successful clade of herbivorous dinosaurs. This skeleton is associated with the first perinate dinosaur specimens from the Atlantic Coastal Plain. The tyrannosauroid and hadrosaurid substantiate one of the only Late Santonian dinosaur faunas and help pinpoint the timing of important anatomical innovations in two widespread dinosaur lineages. The phylogenetic positions of the tyrannosauroid and hadrosaurid show Santonian Appalachian dinosaur faunas are surprisingly comparable to coeval Eurasian ones, and the presence of clades formed only by Appalachian dinosaur taxa establishes a degree of endemism in Appalachian dinosaur assemblages attributable to episodes of vicariance
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Hadrosaurid phylogenetic matrix.txt from Dinosaurs from the Santonian–Campanian Atlantic coastline substantiate phylogenetic signatures of vicariance in Cretaceous North America
2021Co-Authors: Chase Doran BrownsteinAbstract:During the Cretaceous, diversifications and turnovers affected terrestrial vertebrates experiencing the effects of global geographical change. However, the poor fossil record from the Middle Cretaceous has concealed how dinosaurs and other terrestrial vertebrates responded to these events. I describe two dinosaurs from the Santonian to Early Campanian of the obscure North American paleolandmass Appalachia. A revised look at a large, potentially novel theropod shows that it likely belongs to a new clade of tyrannosauroids solely from Appalachia. Another partial skeleton belongs to an early member of the Hadrosauridae, a highly successful clade of herbivorous dinosaurs. This skeleton is associated with the first perinate dinosaur specimens from the Atlantic Coastal Plain. The tyrannosauroid and hadrosaurid substantiate one of the only Late Santonian dinosaur faunas and help pinpoint the timing of important anatomical innovations in two widespread dinosaur lineages. The phylogenetic positions of the tyrannosauroid and hadrosaurid show Santonian Appalachian dinosaur faunas are surprisingly comparable to coeval Eurasian ones, and the presence of clades formed only by Appalachian dinosaur taxa establishes a degree of endemism in Appalachian dinosaur assemblages attributable to episodes of vicariance
