Search

Your search keyword '"Suan, G."' showing total 25 results
Start Over Author "Suan, G."
25 results on '"Suan, G."'

5. Enhanced Arctic-Tethys connectivity ended the Toarcian Oceanic Anoxic Event in NW Europe

Author

Schootbrugge, B. van de, Houben, A.J.P., Ercan, F.E.Z., Verreussel, R., Kerstholt, S., Janssen, N.M.M., Nikitenko, B., Suan, G., Marine Palynology, Marine palynology and palaeoceanography, Coastal dynamics, Fluvial systems and Global change, and Palaeo-ecologie

Subjects
Arctic, Palaeoceanography, carbon isotopes, Dinoflagellate cysts, Carbon isotopes, Geological Survey Netherlands, Toarcian Oceanic Anoxic Event, dinoflagellate cysts, Geology, 2015 Energy, Mesozoic, palaeoceanography
Abstract

The Toarcian Oceanic Anoxic Event (T-OAE, c. 182 Ma) represents a major perturbation of the carbon cycle marked by widespread black shale deposition. Consequently, the onset of the T-OAE has been linked to the combined effects of global warming, high productivity, basin restriction and salinity stratification. However, the processes that led to termination of the event remain elusive. Here, we present palynological data from Arctic Siberia (Russia), the Viking Corridor (offshore Norway) and the Yorkshire Coast (UK), all spanning the upper Pliensbachian - upper Toarcian stages. Rather than a 'dinoflagellate cyst black-out', as recorded in T-OAE strata of NW Europe, both the Arctic and Viking Corridor records show high abundance and dinoflagellate diversity throughout the T-OAE interval as calibrated by C-isotope records. Significantly, in the Arctic Sea and Viking Corridor, numerous species of the Parvocysta and Phallocysta suites make their first appearance in the lower Toarcian Falciferum Zone much earlier than in Europe, where these key dinoflagellate species appeared suddenly during the Bifrons Zone. Our results indicate migrations of Arctic dinoflagellate species, driven by relative sea-level rise in the Viking Corridor and the establishment of a S-directed circulation from the Arctic Sea into the Tethys Ocean. The results support oceanographic models, but are at odds with some interpretations based on geochemical proxies. The migration of Arctic dinoflagellate species coincides with the end of the T-OAE and marks the arrival of oxygenated, low-salinity Arctic waters, triggering a regime change from persistent euxinia to more dynamic oxygen conditions. © Cambridge University Press 2019.

Published
2020

6. Enhanced Arctic-Tethys connectivity ended the Toarcian Oceanic Anoxic Event in NW Europe

Author

van de Schootbrugge, B., Houben, A.J.P., Ercan, F.E.Z., Verreussel, R., Kerstholt, S., Janssen, N.M.M., Nikitenko, B., Suan, G., Marine Palynology, Marine palynology and palaeoceanography, Coastal dynamics, Fluvial systems and Global change, and Palaeo-ecologie

Subjects
Palynology, biology, Dinoflagellate, Toarcian Oceanic Anoxic Event, Geology, Structural basin, biology.organism_classification, Tethys Ocean, Carbon cycle, palaeoceanography, Oceanography, Arctic, Effects of global warming, carbon isotopes, dinoflagellate cysts, Mesozoic
Abstract

The Toarcian Oceanic Anoxic Event (T-OAE, c. 182 Ma) represents a major perturbation of the carbon cycle marked by widespread black shale deposition. Consequently, the onset of the T-OAE has been linked to the combined effects of global warming, high productivity, basin restriction and salinity stratification. However, the processes that led to termination of the event remain elusive. Here, we present palynological data from Arctic Siberia (Russia), the Viking Corridor (offshore Norway) and the Yorkshire Coast (UK), all spanning the upper Pliensbachian – upper Toarcian stages. Rather than a ‘dinoflagellate cyst black-out’, as recorded in T-OAE strata of NW Europe, both the Arctic and Viking Corridor records show high abundance and dinoflagellate diversity throughout the T-OAE interval as calibrated by C-isotope records. Significantly, in the Arctic Sea and Viking Corridor, numerous species of the Parvocysta and Phallocysta suites make their first appearance in the lower Toarcian Falciferum Zone much earlier than in Europe, where these key dinoflagellate species appeared suddenly during the Bifrons Zone. Our results indicate migrations of Arctic dinoflagellate species, driven by relative sea-level rise in the Viking Corridor and the establishment of a S-directed circulation from the Arctic Sea into the Tethys Ocean. The results support oceanographic models, but are at odds with some interpretations based on geochemical proxies. The migration of Arctic dinoflagellate species coincides with the end of the T-OAE and marks the arrival of oxygenated, low-salinity Arctic waters, triggering a regime change from persistent euxinia to more dynamic oxygen conditions.

Published
2020

7. Enhanced Arctic-Tethys connectivity ended the Toarcian Oceanic Anoxic Event in NW Europe

Author

Marine Palynology, Marine palynology and palaeoceanography, Coastal dynamics, Fluvial systems and Global change, Palaeo-ecologie, van de Schootbrugge, B., Houben, A.J.P., Ercan, F.E.Z., Verreussel, R., Kerstholt, S., Janssen, N.M.M., Nikitenko, B., Suan, G., Marine Palynology, Marine palynology and palaeoceanography, Coastal dynamics, Fluvial systems and Global change, Palaeo-ecologie, van de Schootbrugge, B., Houben, A.J.P., Ercan, F.E.Z., Verreussel, R., Kerstholt, S., Janssen, N.M.M., Nikitenko, B., and Suan, G.

Published
2020

8. The Schandelah Scientific Drilling Project: A 25-million year record of Early Jurassic palaeo-environmental change from northern Germany

Author

Van de Schootbrugge, B., Richoz, S., Pross, J., Luppold, F. W., Hunze, S., Wonik, T., Blau, J., Meister, C., Van der Weijst, C. M.H., Suan, G., Fraguas, A., Fiebig, J., Herrle, J. O., Guex, J., Little, C. T.S., Wignall, P. B., Püttmann, W., Oschmann, W., Marine palynology and palaeoceanography, Marine Palynology, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Marine palynology and palaeoceanography, Marine Palynology, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)

Subjects
Stratigraphy, Plant Science, 0603 philosophy, ethics and religion, 050105 experimental psychology, Paleontology, drill core, Chemostratigraphy, 0501 psychology and cognitive sciences, 14. Life underwater, Sedimentology, black shales, Siltstone, Drill core, Extinction event, Ammonite, Early Jurassic, 05 social sciences, sedimentology, Geology, 06 humanities and the arts, Authigenic, language.human_language, 13. Climate action, [SDU]Sciences of the Universe [physics], 060302 philosophy, Facies, language, Black shales, Sedimentary rock, chemostratigraphy, paleontology
Abstract

With the aim to understand prolonged and repeated marine anoxia after the Triassic-Jurassic massextinction event, a continuously cored, 338 metre thick succession of Rhaetian to Toarcian sediments was retrieved close to the village of Schandelah near Braunschweig (Lower Saxony, northern Germany). Here, preliminary biostratigraphical, lithological, sedimentological, geochemical, and geophysical borehole data are presented and discussed. Based on the presence of ammonites, ostracods, benthic foraminifers, calcareous nannofossils, and palynomorphs, all major Late Triassic and Early Jurassic stage boundaries and many of the standard Lower Jurassic ammonite zones could be defined. The deltaic Rhaetian sand- and siltstone succession (Exter Fm) contains evidence for seismic activity probably related to large-scale geodynamic processes. The Hettangian (Lias Alpha) is represented by a thick heterolithic succession composed of shallow marine sandy and silty beds with intercalated organic-rich shale, representing deposition on a shoreface with frequent storm activity. Progressive deepening during the Sinemurian to Toarcian resulted in repeated deposition of laminated organic-rich facies. Periods of relative sea-level fall likely occurred during the Late Hettangian, the Late Sinemurian, and Early Pliensbachian, where a series of hardgrounds occur indicating erosion on the sea floor followed by sea level rise leading to omission, and increased reworking. One of the most conspicuous features of the Lower Jurassic in the Schandelah-1 core is the presence of abundant authigenic carbonates (glendonites, concretions, beef-calcite) within the Upper Pliensbachian with partly very negative C-isotope values (down to -37%o V-PDB) suggesting the anaerobic oxidation of methane. A high-resolution organic carbon isotope record based on 485 analyses shows two major negative carbon isotope excursions (CIEs) within the lowermost Hettangian and Lower Toarcian, respectively. Both excursions coincide with the onset of black shale deposition and are well-known features of these time-intervals in other regions. Despite the fact that black shale deposition also characterizes parts of the Sinemurian and Pliensbachian in similar facies, no large negative CIEs are apparent. The Schandelah-1 core thus provides an unique archive of sedimentary, biotic and geochemical records of long-term Triassic-Jurassic palaeo-environmental change in the European Epicontinental Seaway.

Published
2019
Full Text
View/download PDF

11. The Schandelah scientific drilling project: A 25-million year record of Early Jurassic palaeoenvironmental change from northern Germany

Author

Van de Schootbrugge, B., Richoz, S., Pross, J., Luppold, F. W., Hunze, S., Wonik, T., Blau, J., Meister, C., Van der Weijst, C. M.H., Suan, G., Fraguas, A., Fiebig, J., Herrle, J. O., Guex, J., Little, C. T.S., Wignall, P. B., Püttmann, W., Oschmann, W., Van de Schootbrugge, B., Richoz, S., Pross, J., Luppold, F. W., Hunze, S., Wonik, T., Blau, J., Meister, C., Van der Weijst, C. M.H., Suan, G., Fraguas, A., Fiebig, J., Herrle, J. O., Guex, J., Little, C. T.S., Wignall, P. B., Püttmann, W., and Oschmann, W.

Abstract

With the aim to understand prolonged and repeated marine anoxia after the Triassic-Jurassic massextinction event, a continuously cored, 338 metre thick succession of Rhaetian to Toarcian sediments was retrieved close to the village of Schandelah near Braunschweig (Lower Saxony, northern Germany). Here, preliminary biostratigraphical, lithological, sedimentological, geochemical, and geophysical borehole data are presented and discussed. Based on the presence of ammonites, ostracods, benthic foraminifers, calcareous nannofossils, and palynomorphs, all major Late Triassic and Early Jurassic stage boundaries and many of the standard Lower Jurassic ammonite zones could be defined. The deltaic Rhaetian sand- and siltstone succession (Exter Fm) contains evidence for seismic activity probably related to large-scale geodynamic processes. The Hettangian (Lias Alpha) is represented by a thick heterolithic succession composed of shallow marine sandy and silty beds with intercalated organic-rich shale, representing deposition on a shoreface with frequent storm activity. Progressive deepening during the Sinemurian to Toarcian resulted in repeated deposition of laminated organic-rich facies. Periods of relative sea-level fall likely occurred during the Late Hettangian, the Late Sinemurian, and Early Pliensbachian, where a series of hardgrounds occur indicating erosion on the sea floor followed by sea level rise leading to omission, and increased reworking. One of the most conspicuous features of the Lower Jurassic in the Schandelah-1 core is the presence of abundant authigenic carbonates (glendonites, concretions, beef-calcite) within the Upper Pliensbachian with partly very negative C-isotope values (down to -37%o V-PDB) suggesting the anaerobic oxidation of methane. A high-resolution organic carbon isotope record based on 485 analyses shows two major negative carbon isotope excursions (CIEs) within the lowermost Hettangian and Lower Toarcian, respectively. Both excursions coi

Published
2019

12. The Schandelah scientific drilling project: A 25-million year record of Early Jurassic palaeoenvironmental change from northern Germany

Author

Marine palynology and palaeoceanography, Marine Palynology, Van de Schootbrugge, B., Richoz, S., Pross, J., Luppold, F. W., Hunze, S., Wonik, T., Blau, J., Meister, C., Van der Weijst, C. M.H., Suan, G., Fraguas, A., Fiebig, J., Herrle, J. O., Guex, J., Little, C. T.S., Wignall, P. B., Püttmann, W., Oschmann, W., Marine palynology and palaeoceanography, Marine Palynology, Van de Schootbrugge, B., Richoz, S., Pross, J., Luppold, F. W., Hunze, S., Wonik, T., Blau, J., Meister, C., Van der Weijst, C. M.H., Suan, G., Fraguas, A., Fiebig, J., Herrle, J. O., Guex, J., Little, C. T.S., Wignall, P. B., Püttmann, W., and Oschmann, W.

Published
2019

13. Glendonites track methane seepage in Mesozoic polar seas

Author

Morales, C., Rogov, M., Wierzbowski, H., Ershova, V., Suan, G, Adatte, T., Föllmi, K.B., Tegelaar, E., Reichart, G.-J., de Lange, G.J., Middelburg, J.J., van de Schootbrugge, B., Morales, C., Rogov, M., Wierzbowski, H., Ershova, V., Suan, G, Adatte, T., Föllmi, K.B., Tegelaar, E., Reichart, G.-J., de Lange, G.J., Middelburg, J.J., and van de Schootbrugge, B.

Abstract

During the Phanerozoic, Earth has experienced a number of transientglobal warming events associated with major carbon cycle perturbations.Paradoxically, many of these extreme greenhouse episodesare preceded or followed by cold climate, perhaps even glacial conditions,as inferred from the occurrence of glendonites in high latitudes.Glendonites are pseudomorphs of ikaite (CaCO3·6H2O), a hydratedcarbonate mineral increasingly stable at low temperatures. Here,we show that methane seepage and oxidation provide an overridingcontrol on Mesozoic glendonite formation (i.e., ikaite fossilization).Geochemical and petrological analyses of 33 Early Jurassic to EarlyCretaceous glendonites from five sections in Siberia (Russia) revealthat most of their infilling carbonate phases are reminiscent of methane-derived authigenic carbonates. Bulk glendonites and surroundingsediments exhibit exceptionally high and low carbon isotope values(+20‰ to −45‰ VPDB [Vienna Peedee belemnite]), typical for carbonsources linked to methane generation and oxidation. Gas inclusiondata confirm the presence of methane and longer-chain hydrocarbongases, suggesting a thermogenic source for the methane. Glendonitebearinglayers can be traced for hundreds of kilometers, suggestingwidespread trapping of methane in the sub-seafloor during the Jurassic.As such, glendonites constitute an unexplored archive for detectingpast episodes of methane release and oxidation in polar settings.

Published
2017

14. New insights on the systematics, palaeoecology and palaeobiology of a plesiosaurian with soft tissue preservation from the Toarcian of Holzmaden, Germany

Author

Vincent, P, Allemand, R, Taylor, PD, Suan, G, Maxwell, EE, Vincent, P, Allemand, R, Taylor, PD, Suan, G, and Maxwell, EE

Abstract

© Springer-Verlag Berlin Heidelberg 2017. The attached document is the author’s submitted version of the journal article. You are advised to consult the publisher’s version if you wish to cite from it. The final publication is available at Springer via http://dx.doi.org/10.1007/s00114-017-1472-6, NHM Repository

Published
2017

15. Mochras borehole revisited: a new global standard for Early Jurassic earth history

Author

Hesselbo, S.P., Bjerum, C.J., Hinnov, L.A., MacNiocaill, C., Miller, K.G., Riding, J.B., van de Schootbrugge, B., Abels, H.A., Belcher, C., Blau, J., Browning, J., Cartwright, J., Condon, D., Daines, S., Damborenea, S., Dickson, A., Fraguas, A., Hilgen, F., Hooker, J., Huang, C., Hüsing, S., Jenkyns, H., Korte, C., Krijgsman, W., Lenton, T., Little, C., Manceñido, M., Mattioli, E., Meister, C., Morgan, R., Newton, R., Pálfy, J., Pienkowski, G., Poulton, S., Riccardi, A., Robinson, A., Ruhl, M., Suan, G., Smith, N., Thibault, N., Ullmann, C., Wignall, P., Williford, K., Wonik, T., Xu, W., Marine Palynology, NWO-VENI: Middle Miocene global cooling: climate change through gateway closure, NWO-VENI: Terrestrial climate change and river floodplain dynamics during extreme greenhouse conditions in the Early Eocene, NWO-VICI: The evolution of the Paratethys: the lost sea of Central Eurasia, Paleomagnetism, Stratigraphy & paleontology, Marine palynology and palaeoceanography, Stratigraphy and paleontology, Marine Palynology, NWO-VENI: Middle Miocene global cooling: climate change through gateway closure, NWO-VENI: Terrestrial climate change and river floodplain dynamics during extreme greenhouse conditions in the Early Eocene, NWO-VICI: The evolution of the Paratethys: the lost sea of Central Eurasia, Paleomagnetism, Stratigraphy & paleontology, Marine palynology and palaeoceanography, and Stratigraphy and paleontology

Subjects
Total organic carbon, Extinction event, Series (stratigraphy), Environmental change, Mechanical Engineering, Earth science, lcsh:QE1-996.5, Oceanografía, Hidrología, Recursos Hídricos, Borehole, Energy Engineering and Power Technology, Biota, STRATIGRAPHY, EARLY JURASSIC, BOREHOLE, Ciencias de la Tierra y relacionadas con el Medio Ambiente, lcsh:Geology, purl.org/becyt/ford/1 [https], purl.org/becyt/ford/1.5 [https], Paleontology, Stratigraphy, DRILLING, Glacial period, Geology, CIENCIAS NATURALES Y EXACTAS, GLOBAL STANDARD
Abstract

The Early Jurassic epoch was a time of extreme environmental change: there are well-documented examples of rapid transitions from cold, or even glacial, climates to super greenhouse events, the latter characterized worldwide by hugely enhanced organic carbon burial, multiple large isotopic anomalies, global sea-level change, and mass extinction (Price, 1999; Hesselbo et al., 2000; Jenkyns, 2010; Korte and Hesselbo, 2011). These icehouse–greenhouse events not only reflect changes in the global climate system but are also thought to have had significant influence on the evolution of Jurassic marine biota (e.g. van de Schootbrugge et al., 2005; Fraguas et al., 2012). Furthermore, the events may serve as analogues for present-day and future environmental transitions. Although our knowledge of specific global change events within the Early Jurassic is rapidly improving, such as the Toarcian oceanic anoxic event (or T-OAE), we still do not have a comprehensive understanding of the timing, pacing, or triggers for these environmental perturbations, principally because of the temporally fragmentary nature of the existing data sets. The major goal for this proposed ICDP project is therefore to produce a new global standard for these key 25 million years of earth history by re-drilling and doublecoring a 45 yr old borehole at Mochras Farm on the edge of Cardigan Bay, Wales, and developing an integrated stratigraphy for the cored material. The new data sets will be applied to understand fundamental questions about the longand short-term evolution of the earth system. Cycles that occur regionally and that provisionally appear in the Mochras logs will allow evaluation of the extent to which major environmental change events are astronomically forced, resulting from internal system dynamics, or are triggered by deepearth processes. Fil: Hesselbo, S. P.. University Of Exeter; Reino Unido Fil: Bjerrum, C. J.. Universidad de Copenhagen; Dinamarca Fil: Hinnov, L. A.. University Johns Hopkins; Estados Unidos Fil: Mac Niocaill, C.. University of Oxford; Reino Unido Fil: Miller, K. G.. State University of New Jersey; Estados Unidos Fil: Riding, J. B.. British Geological Survey; Reino Unido Fil: Van de Schootbrugge, B.. University of Utrecht; Países Bajos Fil: Abels, H.. The Mochras Revisited Science Team; Reino Unido Fil: Belcher, C.. The Mochras Revisited Science Team; Reino Unido Fil: Blau, J.. The Mochras Revisited Science Team; Reino Unido Fil: Browning, J.. The Mochras Revisited Science Team; Reino Unido Fil: Cartwright, J.. The Mochras Revisited Science Team; Reino Unido Fil: Condon, D.. The Mochras Revisited Science Team; Reino Unido Fil: Daines, S.. The Mochras Revisited Science Team; Reino Unido Fil: Damborenea, S.. The Mochras Revisited Science Team; Reino Unido Fil: Dickson, A.. The Mochras Revisited Science Team; Reino Unido Fil: Fraguas, A.. The Mochras Revisited Science Team; Reino Unido Fil: Hilgen, F.. The Mochras Revisited Science Team; Reino Unido Fil: Hooker, J.. The Mochras Revisited Science Team; Reino Unido Fil: Huang, C.. The Mochras Revisited Science Team; Reino Unido Fil: Huesing, S.. The Mochras Revisited Science Team; Reino Unido Fil: Jenkyns, H.. The Mochras Revisited Science Team; Reino Unido Fil: Korte, C.. The Mochras Revisited Science Team; Reino Unido Fil: Krijgsman, W.. The Mochras Revisited Science Team; Reino Unido Fil: Lenton, T.. The Mochras Revisited Science Team; Reino Unido Fil: Little, C.. The Mochras Revisited Science Team; Reino Unido Fil: Manceñido, Miguel Oscar. The Mochras Revisited Science Team; Reino Unido. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Mattioli, E.. The Mochras Revisited Science Team; Reino Unido Fil: Meister, C.. The Mochras Revisited Science Team; Reino Unido Fil: Morgan, R.. The Mochras Revisited Science Team; Reino Unido Fil: Newton, R.. The Mochras Revisited Science Team; Reino Unido Fil: Pálfy, J.. The Mochras Revisited Science Team; Reino Unido Fil: Pienkowski, G.. The Mochras Revisited Science Team; Reino Unido Fil: Poulton, S.. The Mochras Revisited Science Team; Reino Unido Fil: Riccardi, A.. The Mochras Revisited Science Team; Reino Unido Fil: Robinson, A.. The Mochras Revisited Science Team; Reino Unido Fil: Ruhl, M.. The Mochras Revisited Science Team; Reino Unido Fil: Suan, G.. The Mochras Revisited Science Team; Reino Unido Fil: Smith, N.. The Mochras Revisited Science Team; Reino Unido Fil: Thibault, N.. The Mochras Revisited Science Team; Reino Unido Fil: Ullmann, C.. The Mochras Revisited Science Team; Reino Unido Fil: Wignall, P.. The Mochras Revisited Science Team; Reino Unido Fil: Williford, K.. The Mochras Revisited Science Team; Reino Unido Fil: Wonik, T.. The Mochras Revisited Science Team; Reino Unido Fil: Xu, W.. The Mochras Revisited Science Team; Reino Unido

Published
2013
Full Text
View/download PDF

16. Marine vertebrate remains from the Toarcian-Aalenian succession of southern Beaujolais, Rhone, France

Author

Vincent, P., Martin, J.E., Fischer, V., Suan, G., Khalloufi, B., Sucheras-Marx, B., Lena, A., Janneau, K., Rousselle, B., and Rulleau, L.

Subjects
Aalenian, Actinopterygii, Toarcian, Ichthyosauria, France, Rhone R, Crocodylomorpha, Plesiosauria
Abstract

A previously undocumented marine vertebrate fauna comprising ichthyosaur, plesiosaur, marine crocodilian and fish remains from the Toarcian-Aalenian succession at Lafarge quarry, southern Beaujolais (Rhone, France) is described on the basis of both historical collections and new discoveries. The taxonomic composition of the Lafarge quarry marine vertebrate assemblage highlights its cosmopolitan nature and strong relationships with taxa known from elsewhere in Europe. Several groups are recorded for the first time in the Toarcian-Aalenian succession of France, implying new palaeobiogeographic interpretations and prompting discussion of marine amniote diversity during this interval.

Published
2013

17. A longirostrine Temnodontosaurus (Ichthyosauria) with comments on Early Jurassic ichthyosaur niche partitioning and disparity

Author

Martin, J.E., Fischer, V., Vincent, P., and Suan, G

Subjects
Temnodontosaurus, Ichthyosauria
Abstract

We describe an almost complete ichthyosaur skeleton from the middle Toarcian (Lower Jurassic) of the Beaujolais foothills near Lyon, France, and assign it to Temnodontosaurus azerguensis sp. nov. This new species exhibits cranial peculiarities such as a thin, elongated and possibly edentulous rostrum, as well as a reduced quadrate. These characters indicate dietary preferences that markedly differ from other species referred to Temnodontosaurus, a genus previously considered as the top predator of the Early Jurassic seas. Despite a conservative postcranial skeleton, we propose that Temnodontosaurus is one of the most ecologically disparate genera of ichthyosaurs, including apex predators and now a soft prey longirostrine hunter. Ammonites collected from the same stratigraphic level as the described specimen indicate that the new species is somewhat younger (bifrons ammonite zone) than the most known Toarcian ichthyosaurs and therefore slightly postdates the interval of severe environmental changes and marine invertebrate extinctions known as the Toarcian Oceanic Anoxic Event. The present study therefore raises the question of whether postcrisis recovery of vertebrate faunas, including the radiation of Temnodontosaurus into a new ecological niche, may have been a consequence of marine ecosystem reorganization across this event.

Published
2012

18. A new longirostrine ichthyosaur (Reptilia) from the Toarcian of France broadens the ecological diversity of the genus Temnodontosaurus

Author

Martin, J.E., Fischer, V., Vincent, P., and Suan, G

Abstract

The ichthyosaur genus Temnodontosaurus has always been viewed as a top predator of the Early Jurassic marine environments, while other contemporaneous ichthyosaurs such as leptonectids and stenopterygiids were occupying the lower trophic levels. We describe here an almost complete skeleton of this successful genus from the middle Toarcian (Lower Jurassic) of the Beaujolais foothills near Lyon, France, and assign it to a new species of Temnodontosaurus. This specimen exhibits cranial peculiarities such as a thin, elongated, and likely edentulous rostrum, as well as a reduced quadrate. Such morphological combination indicates dietary preferences that markedly differ from other species referred to as Temnodontosaurus. Despite a conservative postcranial skeleton, we propose that Temnodontosaurus is one of the most ecologically diverse genera of ichthyosaurs, including apex predators, small and soft prey longirostrine hunters, and generalized forms. Ammonites collected along the described specimen indicate that the new species is younger (bifrons ammonite zone) than most known Toarcian ichthyosaurs and therefore slightly postdates the severe environmental changes and marine invertebrate extinctions that occur during the Toarcian Oceanic Anoxic Event. The present study hence raises the question whether the speciation of Temnodontosaurus towards a new ecological niche, may have been a consequence of the post-crisis marine ecosystem reorganization.

Published
2011

19. Mochras borehole revisited: A new global standard for Early Jurassic Earth history

Author

Marine Palynology, NWO-VENI: Middle Miocene global cooling: climate change through gateway closure, NWO-VENI: Terrestrial climate change and river floodplain dynamics during extreme greenhouse conditions in the Early Eocene, NWO-VICI: The evolution of the Paratethys: the lost sea of Central Eurasia, Paleomagnetism, Stratigraphy & paleontology, Marine palynology and palaeoceanography, Stratigraphy and paleontology, Hesselbo, S.P., Bjerum, C.J., Hinnov, L.A., MacNiocaill, C., Miller, K.G., Riding, J.B., van de Schootbrugge, B., Abels, H.A., Belcher, C., Blau, J., Browning, J., Cartwright, J., Condon, D., Daines, S., Damborenea, S., Dickson, A., Fraguas, A., Hilgen, F., Hooker, J., Huang, C., Hüsing, S., Jenkyns, H., Korte, C., Krijgsman, W., Lenton, T., Little, C., Manceñido, M., Mattioli, E., Meister, C., Morgan, R., Newton, R., Pálfy, J., Pienkowski, G., Poulton, S., Riccardi, A., Robinson, A., Ruhl, M., Suan, G., Smith, N., Thibault, N., Ullmann, C., Wignall, P., Williford, K., Wonik, T., Xu, W., Marine Palynology, NWO-VENI: Middle Miocene global cooling: climate change through gateway closure, NWO-VENI: Terrestrial climate change and river floodplain dynamics during extreme greenhouse conditions in the Early Eocene, NWO-VICI: The evolution of the Paratethys: the lost sea of Central Eurasia, Paleomagnetism, Stratigraphy & paleontology, Marine palynology and palaeoceanography, Stratigraphy and paleontology, Hesselbo, S.P., Bjerum, C.J., Hinnov, L.A., MacNiocaill, C., Miller, K.G., Riding, J.B., van de Schootbrugge, B., Abels, H.A., Belcher, C., Blau, J., Browning, J., Cartwright, J., Condon, D., Daines, S., Damborenea, S., Dickson, A., Fraguas, A., Hilgen, F., Hooker, J., Huang, C., Hüsing, S., Jenkyns, H., Korte, C., Krijgsman, W., Lenton, T., Little, C., Manceñido, M., Mattioli, E., Meister, C., Morgan, R., Newton, R., Pálfy, J., Pienkowski, G., Poulton, S., Riccardi, A., Robinson, A., Ruhl, M., Suan, G., Smith, N., Thibault, N., Ullmann, C., Wignall, P., Williford, K., Wonik, T., and Xu, W.

Published
2013

20. Impact of infection on the growth of children from 0 to 2 years in an urban West African community.

Author

Rowland, Michael G. M., Rowland, Suan G. J. Goh, and Cole, Timothy J.

Subjects
NEWBORN infants, DEVELOPMENTAL biology, RESPIRATORY infections, WEIGHT gain, DIARRHEA
Abstract

To determine the relationship between growth and morbidity in the first 2 y of life, we studied a cohort of 126 newborns in a Gambian township. Mean weight-for-age exceeded the National Center for Health Statistics (NCHS) standards in the first half of infancy but there was a mean deficit of 1.2 kg by age 1 y. Only two diseases contributed significantly to weight faltering: diarrheal diseases were estimated to cause one-half of the deficit and lower respiratory tract infections (LRTI) one-quarter. LRTI reduced weight gain in young children by 14.7 g/d of infection and diarrheal diseases in weaning infants by 14.4 g/d. Diarrhea had no significant impact on the growth of exclusively breast-fed infants. Growth velocity was normal in the second year of life, despite continuing infections. [ABSTRACT FROM AUTHOR]

Published
1988
Full Text
View/download PDF

22. School Board's Authority To Ban Book Faces a Federal-Court Test in Maine.

Author

Foster, Suan G.

Subjects
EDUCATION, CENSORSHIP, SCHOOL administration, DISTRICT courts, SCHOOL districts, ACTIONS & defenses (Law)
Abstract

The article offers education-related cases in Maine in 1981. The ban executed by the school committee of Baileyville for the book "365 Days," by Ronald J. Glasser from the high school library will be challenged by the District Court in Bangor. A similar case, Island Trees Union Free School District versus (v) Steven Pico, is expecting action from the Supreme Court.

Published
1981

23. Regional heterothermies recorded in the oxygen isotope composition of harbour seal skeletal elements.

Author

Séon N, Amiot R, Suan G, Lécuyer C, Fourel F, Vinçon-Laugier A, Charbonnier S, and Vincent P

Subjects
Animals, Female, Male, Oxygen Isotopes analysis, Bone and Bones, Fossils, France, Phoca
Abstract

Regional heterothermy is a strategy used by marine mammals to maintain a high and stable core body temperature, but its identification needs in situ measurements difficult to set up in extant wild organisms and inapplicable to extinct ones. We have analysed the oxygen isotope composition of bioapatite phosphate (δ 18 O p ) from one permanent tooth and from thirty-six skeletal elements of one adult male harbour seal (Phoca vitulina) from the Baie de Somme (Hauts-de-France, France). We propose that the observed intra-skeletal δ 18 O p variability reflects tissue temperature heterogeneities typical of the pinniped regional heterothermy strategy. Our δ 18 O p data indicate that bone hydroxylapatite from harbour seal autopod skeletal elements (metacarpals, metatarsals, and phalanxes) mineralises at a lower temperature than that of the bone from the axial skeleton (e.g. vertebrae, ribs, and girdle bones). The results suggest that it is possible to locate a history of regional heterothermies in amphibious marine vertebrates using the δ 18 O p values of their mineralised tissues. This enables direct evaluation of the thermophysiology of both modern and fossil Pinnipedia from their skeletons opening perspectives on understanding their thermal adaptation to the marine environment in the fossil record. In addition to thermophysiology, oxygen isotope data from the permanent teeth of Pinnipedia, which are formed during the in utero phase from body fluid of the mother and at a stable temperature, could be valuable for locating the geographical areas inhabited by existing Pinnipedia females during their gestation period., Competing Interests: Declaration of competing interest The authors declare to have any competing interests., (Copyright © 2024. Published by Elsevier Ltd.)

Published
2024
Full Text
View/download PDF

24. Determination of water balance maintenance in Orcinus orca and Tursiops truncatus using oxygen isotopes.

Author

Séon N, Brasseur I, Scala C, Tacail T, Catteau S, Fourel F, Vincent P, Lécuyer C, Suan G, Charbonnier S, Vinçon-Laugier A, and Amiot R

Subjects
Animals, Humans, Oxygen Isotopes, Steam, Cetacea physiology, Whale, Killer, Bottle-Nosed Dolphin
Abstract

The secondary adaptation of Cetacea to a fully marine lifestyle raises the question of their ability to maintain their water balance in a hyperosmotic environment. Cetacea have access to four potential sources of water: surrounding salt oceanic water, dietary free water, metabolic water and inhaled water vapour to a lesser degree. Here, we measured the 18O/16O oxygen isotope ratio of blood plasma from 13 specimens belonging to two species of Cetacea raised under human care (four killer whales Orcinus orca, nine common bottlenose dolphins Tursiops truncatus) to investigate and quantify the contribution of preformed water (dietary free water, surrounding salt oceanic water) and metabolic water to Cetacea body water using a box-modelling approach. The oxygen isotope composition of Cetacea blood plasma indicates that dietary free water and metabolic water contribute to more than 90% of the total water input in weight for cetaceans, with the remaining 10% consisting of inhaled water vapour and surrounding water accidentally ingested or absorbed through the skin. Moreover, the contribution of metabolic water appears to be more important in organisms with a more lipid-rich diet. Beyond these physiological and conservation biology implications, this study opens up questions that need to be addressed, such as the applicability of the oxygen isotope composition of cetacean body fluids and skeletal elements as an environmental proxy of the oxygen isotope composition of present and past marine waters., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2023. Published by The Company of Biologists Ltd.)

Published
2023
Full Text
View/download PDF

25. New insights on the systematics, palaeoecology and palaeobiology of a plesiosaurian with soft tissue preservation from the Toarcian of Holzmaden, Germany.

Author

Vincent P, Allemand R, Taylor PD, Suan G, and Maxwell EE

Subjects
Animals, Germany, Bone and Bones anatomy & histology, Fossils, Phylogeny, Reptiles anatomy & histology, Reptiles classification
Abstract

The Posidonienschiefer Formation (Toarcian) of Holzmaden, Baden-Württemberg in southwestern Germany has yielded several excellently preserved plesiosaurian specimens and received considerable research attention. The plesiosaurians found within these deposits are always significantly outnumbered by ichthyosaurs, and close examination of these rare specimens is crucial to a better understanding of the diversity and palaeoecology of Plesiosauria in this very peculiar ecosystem. The plesiosaurian specimen SMNS 51945 found in this area is a juvenile individual consisting of a partial, crushed skull and an exquisitely preserved post-cranial skeleton. Its anatomical characters seem to differ from the long-necked plesiosauroids Microcleidus brachypterygius and Seeleyosaurus guilelmiimperatoris that are the most abundant taxa within the plesiosaurian assemblage. The post-cranial skeleton preserves very likely soft tissues composed of buff-coloured and dark-coloured structures around the vertebral column and hindlimb of the animal. A network of buff-coloured fibres located posterior to the hindlimb most likely represents phosphatised collagen fibres as already found in some ichthyosaur specimens, confirming that wing area in plesiosaurians was much larger than that suggested by skeletal remains alone. The specimen also contains gastroliths (sand-sized grains mainly composed of quartz) in the stomach cavity suggesting the animal spent at least some of its time in shallow coastal waters, tens or hundreds of kilometres from the final place of burial.

Published
2017
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results