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1. Carbon and Nitrogen Cycle Dynamic in Continental Late-Carboniferous to Early Permian Basins of Eastern Pangea (Northeastern Massif Central, France)

Author: Mathilde Mercuzot, Christophe Thomazo, Johann Schnyder, Pierre Pellenard, François Baudin, Anne-Catherine Pierson-Wickmann, Pierre Sans-Jofre, Sylvie Bourquin, Laurent Beccaletto, Anne-Lise Santoni, Georges Gand, Matthieu Buisson, Laure Glé, Thomas Munier, Antonios Saloume, Mohamed Boussaid, and Tracy Boucher
Subjects: late Paleozoic, continental basin, carbon, nitrogen, isotope geochemistry, organic matter, Science
Abstract: Late Carboniferous to early Permian organic-rich sedimentary successions of late-orogenic continental basins from the northeastern Massif Central (France) coincide with both the Variscan mountain dismantling and the acme of the long-lasting Late Paleozoic Ice Age. Here, we investigate the carbon and nitrogen cycles in the newly dated sedimentary successions of the Decize–La Machine and Autun basins during these geodynamic and climate upheavals. The sedimentary organic matter has been analyzed through Rock-Eval pyrolysis, palynofacies and elemental and isotope geochemistry along cored-wells and outcropping sections, previously accurately defined in terms of paleo-depositional environments. Rock-Eval and palynofacies data have evidenced two origins of organic matter: a phytoplanktonic/bacterial lacustrine origin (Type I organic matter, organic δ13C values around −23.5‰), and a terrestrial origin (vascular land plants, Type III organic matter, organic δ13C values around −20‰), mixed in the deltaic-lacustrine sediments during background sedimentation (mean organic δ13C values around −22‰). Episodes of high organic matter storage, reflected by black shales and coal-bearing deposits (total organic carbon up to 20 and 70%, respectively) are also recognized in the successions, and are characterized by large negative organic carbon isotope excursions down to −29‰. We suggest that these negative isotope excursions reflect secondary processes, such as organic matter remineralization and/or secondary productivity varying under strict local controls, or possibly larger scale climate controls. At times, these negative δ13C excursions are paired with positive δ15N excursions up to +10‰, reflecting water column denitrification and anammox during lake-water stratification episodes. Together, these isotopic signals (i.e., low sedimentary organic δ13C associated with high bulk δ15N values) indicate periods of high primary productivity of surface waters, where nitrogen and carbon cycles are spatially decoupled. These local processes on the sedimentary isotope archives may partially blur our ability to directly reconstruct paleoclimate variations in such continental settings using only C and N isotopes. At last, we explore an organic δ13C-based mixing model to propose ways to disentangle autochthonous versus allochthonous origin of organic matter in lacustrine continental settings.
Published: 2021
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2. Palaeobiogeography of the genus Latochara (fossil Charophyta) in the Upper Jurassic of Southern Europe. New data from Oléron Island (France)

Author: Carles Martín-Closas, Jean-Paul Colin, Jean-Paul Billon-Bruyat, Abder El-Albani, Jean-Michel Mazin, and Johann Schnyder
Subjects: Charophytes, ostracods, vertebrates, Tithonian, France, bioprovinces, Geology, QE1-996.5
Abstract: A charophyte assemblage including Latochara tenuicostata (PECK 1937) and Mesochara gr. voluta (PECK 1937) was found in the Lower Tithonian bone-bed 148 of the stratigraphic section at the Pointe de Chassiron, Oléron Island (Charente-Maritime, Southwestern France). This bed, which is well known for its rich and diverse fauna of tetrapods, was deposited in a margino-littoral environment of Purbeckian facies in the Late Jurassic Charente palaeogulf. The occurrence of Latochara at Oléron Island is the most southern location known in the distribution of this genus during the Late Jurassic. This suggests that the boundary between the charophyte Boreal and Tethyan provinces, defined on the basis of this distribution, is not solely determined by latitudinal (i.e. thermal) factors. Ecological factors such as salinity and competition with other charophyte families are hypothesized as alternative explanations.
Published: 2008
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3. Do soft sediment deformations in the Late Triassic and Early Jurassic of the UK record seismic activity during the break-up of Pangea?

Author: Marine Laborde-Casadaban, Sandra Borderie, Rob Raine, Catherine Homberg, Johann Schnyder, Sorbonne Université (SU), Institut des Sciences de la Terre de Paris (iSTeP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 (LOG), Institut national des sciences de l'Univers (INSU - CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Nord]), and Geological Survey of Northern Ireland, Dundonald House, Upper Newtownards Road, BT4 3SB Belfast, Northern Ireland, United Kingdom
Subjects: Lithology, Paleontology, Sediment, Geology, Context (language use), Active fault, Geodynamics, Structural basin, Tectonics, [SDU]Sciences of the Universe [physics], Sedimentary rock, ComputingMilieux_MISCELLANEOUS
Abstract: The lagoonal and shallow marine sediments of the Penarth Group in the UK span the Triassic–Jurassic boundary. These sediments contain several disturbed levels with soft sediment deformations (SSDs), such as synsedimentary faults, injective domes, recumbent folds and slumps that are recognised in most basins from SW England and South Wales to NW Northern Ireland. Field observations, notably the close link of the SSDs to active faults, attest an earthquake origin of the SSDs. Fluids, faults, overpressure and lithology guided the style of the SSDs and their distribution in the sedimentary sections. Analysis of the directional data relating to SSDs in each disturbed level shows preferred orientations of deformation, which correspond to the local state of stress at the time. We favour a series of earthquakes, rather than a single mega-event as a trigger of the observed features. The active local extensional tectonic context was driven by the opening of the Permo-Triassic basins in Western Europe. The data from the SSDs in the UK suggest the development of a multi-directional, mosaic-style extensional context to occur during this early phase of the break-up of Pangea. Our integrated tectonic/sedimentary study suggests that directional data from faults, injective domes, recumbent folds and slumps preserved in sediments are reliable to reconstruct past seismic activity and basin geodynamics.
Published: 2021
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4. Long-term lacustrine paleo-productivity and/or paleo-anoxia trends controlled by eccentricity cycles in the continental Autun Basin (France) at the Carboniferous/Permian boundary

Author: Mathieu Martinez, François Baudin, Johann Schnyder, Sylvie Bourquin, Mathilde Mercuzot, Laurent Beccaletto, Christophe Thomazo, Pierre Pellenard, Institut des Sciences de la Terre de Paris (iSTeP), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS), Géosciences Rennes (GR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS), Biogéosciences [UMR 6282] [Dijon] (BGS), Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique (CNRS), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Dubigeon, Isabelle, Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Biogéosciences [UMR 6282] (BGS), and Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Milankovitch cycles, 010504 meteorology & atmospheric sciences, Permian, Geochemistry, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, 15. Life on land, Cyclostratigraphy, Structural basin, 010502 geochemistry & geophysics, 01 natural sciences, Sedimentary depositional environment, 13. Climate action, Carboniferous, Facies, [SDU.STU] Sciences of the Universe [physics]/Earth Sciences, Oil shale, Geology, 0105 earth and related environmental sciences
Abstract: The organic-rich lacustrine beds of the Autun Basin (France) were deposited from the late Gzhelian (late Carboniferous) to the Sakmarian (early Permian), encompassing the Carboniferous-Permian boundary (∼299 Ma). Those deposits reach up to 1500 m thick, and correspond to a tropical, intra-mountainous late-orogenic basin infilling associated with the Variscan orogeny (Marteau, 1983; Schneider et al., 2006). Organic-rich and laminated facies are attributed to distal lacustrine environments which sometimes alternate with silty to sandy rich deltaic depositional environments (Mercuzot et al., 2019). The four successive formations (respectively the Igornay, Muse, Surmoulin and Millery fms) yield series of oil-shale beds (successively the Moloy, Igornay, Lally Muse, Surmoulin and Les Télots beds) (Marteau, 1983; Garel et al., 2017). The oil-shale beds are at least several m thick in the basin, except for the “Margenne” boghead bed which is only 0.3 m thick (Marteau, 1983; Garel et al., 2017). Recently, accurate U-Pb ages obtained on zircons from volcanic layers of the Autun Basin have placed the Carboniferous-Permian boundary within the Lally oil-shale beds (Pellenard et al., 2017).In this work, we present a detailed study of the 364-m thick Chevrey 1 core, based on a Rock-Eval pyrolysis survey. The Chevrey 1 core encompasses the successive Igornay and Muse fms., including the Lally oil shale bed and the C/P boundary. TOC varies from 0.2 to 21 wt%, whereas HI values range from 22 to 421 mgHC/gTOC. The Lally oil-shale bed seems to correspond to a 2.5-m thick interval of maximum organic preservation between -145.02 m and -142.55 m, with TOC peaks reaching 12-21 wt%. However, the broad organic-rich interval seems much larger, with TOC around 6.1 wt% on average and HI values of 282 mgHC/gTOC on average between -157.3 m and -126.1 m. Moreover, a long-term progressive increase of TOC accumulation, highlighted by several organic pulses is obvious, starting at -282.4 m and pre-dating the Lally oil shale bed occurrence. We thus evidence for the first time that the Lally oil shale bed corresponds to the short-lived apex of a long-term lacustrine organic rich sequence of increasing paleo-productivity and/or paleo-anoxia that is ∼ 200m in thickness and therefore, is not only limited to a thin, (pluri)-meter-thick organic rich interval associated with short-lived anoxia and/or primary productivity pulse, as previously admitted. These findings rise the question of the paleoenvironmental mechanism(s) behind the occurrence of oil-shale intervals within the Autun Basin. Although further works are needed to fully understand those mechanisms, a preliminary cyclostratigraphy study using the Chevrey 1 TOC record suggests that the organic accumulation was likely controlled by climatic cycles in the Milankovitch frequency bands, and that the ∼ 200 m long-term organic trend may be linked to ~2 Myrs eccentricity.
Published: 2020

5. Formation of microbial organic carbonates during the Late Jurassic from the Northern Tethys (Amu Darya Basin, Uzbekistan): implications for Jurassic anoxic events

Author: Pierre Pellenard, Vincent Grossi, Pieter T. Visscher, Laurent Riquier, Cécile Gaborieau, Philippe Razin, Victor Dupias, Olivier Mathieu, Marie-Françoise Brunet, Johann Schnyder, Raymond Enay, Mehdi Carmeille, Raphaël Bourillot, Géoressources et environnement, Institut Polytechnique de Bordeaux (Bordeaux INP)-Université Bordeaux Montaigne (UBM), Biogéosciences [UMR 6282] (BGS), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre de Paris (iSTeP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Sorbonne Université (SU), Paléoenvironnemements Paléoclimats, Bassins (ISTEP-PPB), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), 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), Institut de Mécanique et d'Ingénierie (I2M), Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Arts et Métiers Sciences et Technologies, HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM), Departments of Marine Sciences & Geosciences, University of Connecticut (UCONN), Study funded by Total S.A., Institut Polytechnique de Bordeaux (Bordeaux INP)-Université Bordeaux Montaigne, Biogéosciences [UMR 6282] [Dijon] (BGS), Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS), 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), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), HESAM Université (HESAM)-HESAM Université (HESAM), Institut de Mécanique et d'Ingénierie de Bordeaux (I2M), Université de Bordeaux (UB)-École Nationale Supérieure d'Arts et Métiers (ENSAM), Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-Arts et Métiers Sciences et Technologies, and HESAM Université (HESAM)-HESAM Université (HESAM)-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
Subjects: microbial/laminated sediments, 52 anoxia, 010504 meteorology & atmospheric sciences, Geochemistry, Late Jurassic, 02 engineering and technology, Oceanography, 01 natural sciences, chemistry.chemical_compound, Anoxia, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Marl, 0202 electrical engineering, electronic engineering, information engineering, Amu Darya Basin, Organic matter, 14. Life underwater, Microbial mat, 0105 earth and related environmental sciences, Stable isotopes, Total organic carbon, Sabkha, chemistry.chemical_classification, Global and Planetary Change, geography, geography.geographical_feature_category, 020206 networking & telecommunications, organic-rich carbonates, stable isotopes 53, 15. Life on land, Cretaceous, Palynofacies, chemistry, 13. Climate action, [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, Carbonate, Geology
Abstract: 23 pages; International audience; The Late Jurassic was a period of major global carbon cycle perturbations with episodes of anoxia leading to regional accumulation of organic matter in sediments worldwide. The Tubiegatan section (SW Gissar Mountains, Uzbekistan) located in the Northern Tethys, shows atypical organic-rich limestone and marl deposits (up to 6% of total organic carbon) marked by pronounced negative excursions of δ13Ccarb (amplitude of ca. 12‰) and δ13Corg (amplitude of ca. 4‰) recorded during the Middle Oxfordian (Transversarium Zone). A transdisciplinary approach including sedimentology, palynofacies characterization, mineralogy, organic and inorganic geochemistry was carried out to elucidate the origin of these organic-rich deposits. Highest TOC are measured in nodular limestones, and lowest δ13Ccarb values in thinly laminated facies consisting in alternances of infra-millimeter-thick organic and carbonate laminae. In the latter, the presence of organic-carbonate peloids and of possible remnants of exopolymeric substances associated with clay indicate that these structures are probably mineralized laminated benthic microbial mats (i.e., stromatolites). Rock-Eval pyrolysis coupled to palynofacies analyses point to a dominant altered marine organic matter of probable algal/microbial origin, with subordinate continental phytoclasts inputs in the upper part of the organic-rich interval. Trace elements (U/Th, V/Cr and Mo/Al ratios) indicate two anoxic episodes coinciding with the highest TOC, punctuated by dysoxic periods. Such O2-depleted conditions have allowed the preservation and probably the development of anaerobic microbial communities in the microbial mats. In these latter, sulfate reduction probably had a significant contribution to the production of carbonates, which would explain the precipitation of pyrite and the relatively low δ13Ccarb values. The progressive decrease then disappearance of kaolinite from the base of the organic-rich interval, is interpreted as a progressive aridification of the Amu Darya Basin during the Transversarium Zone, culminating with the progradation of a large-scale gypsum sabkha overlying the organic deposits. Overall, the organic-rich deposits could record the onset of the disconnection of the Amu Darya Basin from the open sea to the south, induced by compression and subsequent uplifts in the Afghan and Central Iranian blocks. The elevated evaporation, coupled with the presence of hydrological barriers (such as coral reefs) could have led to the formation of local to regional anoxic conditions in the Amu Darya Basin. Similar microbial organic accumulations are recently known throughout the Tethys (e.g., Arabian Plate, Western Europe) and from other oceans (e.g., Central Atlantic, Pacific) during the Late Jurassic, suggesting common controlling factors. The increase of organic matter storage worldwide coupled with potential methane release could have in turn induced major perturbations of the carbon cycle during the Oxfordian-Kimmeridgian interval. The relatively shallow anoxia model proposed in this study contrasts with the well-known organic carbon-rich pelagic models proposed for the Jurassic anoxia (e.g., Toarcian, Kimmeridgian) and Cretaceous OAEs.
Published: 2020
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6. The proposal of a GSSP for the Berriasian Stage (Cretaceous System): Part 1

Author: Petr Pruner, Philip Copestake, Andrea Svobodová, Bruno Galbrun, O. S. Dzyuba, Šimon Kdýr, Luc G. Bulot, Alberto Carlos Riccardi, Petr Schnabl, Chris Hunt, Martin Košťák, Terry P. Poulton, Johann Schnyder, Lucie Vaňková, Luis Lena, William A.P. Wimbledon, Camille Frau, Krýstina Šifnerová, Tiiu Elbra, Daniela Reháková, and Sorbonne Université (SU)
Subjects: 010506 paleontology, Series (stratigraphy), global correlation, Range (biology), Boundary (topology), 15. Life on land, J/K boundary, 010502 geochemistry & geophysics, 01 natural sciences, Cretaceous, Calpionella alpina Subzone, Global Boundary Stratotype Section and Point, GSSP definition, Paleontology, markers and proxies, Stage (stratigraphy), [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, Berriasian, QE, Geology, Magnetostratigraphy, 0105 earth and related environmental sciences, Subboreal
Abstract: Here in the first part of this publication we discuss the possibilities for the selection of a GSSP for the Berriasian Stage of the Cretaceous System, based on the established methods for correlation in the Tithonian/Berriasian interval. This will be followed, in the second part, by an account of the stratigraphic evidence that justifies the locality of Tre Maroua (Hautes-Alpes, SE France) as the proposed GSSP. Here we discuss the possibilities for correlation in the historical J/K boundary interval, and the evolution of thinking on the positioning of the boundary over recent generations, and in relation to research in the last ten years. The Tithonian/Berriasian boundary level is accepted as occurring within magnetosubzone M19n.2n. The detailed distribution of calpionellids has been recorded at numerous sites, tied to magnetostratigraphy, and the base of the calpionellid Alpina Zone is taken to define the base of the Berriasian Stage. This is at a level just below the distinctive reversed magnetic subzone M19n.1r (the so-called Brodno reversal). We discuss a wide range of magnetostratigraphic and biostratigraphic data from key localities globally, in the type Berriasian areas of France and wider regions (Le Chouet, Saint Bertrand, Puerto Escano, Rio Argos, Bosso, Brodno, Kurovice, Theodosia etc.). The characteristic datums that typify the J/K boundary interval in Tethys and its extensions are detailed, and the correlative viability of various fossil groups is discussed. The boundary level is correlated to well-known J/K sections globally, and a series of secondary markers and proxies are indicated which assist wider correlation. Particularly significant are the primary basal Berriasian marker, the base of the Alpina Subzone (marked by dominance of small Calpionella alpina, Crassicollaria parvula and Tintinopsella carpathica) and secondary markers bracketing the base of the Calpionella Zone, notably the FOs of the calcareous nannofossil species Nannoconus wintereri (just below the boundary) and the FO of Nannoconus steinmannii minor (just above). Notable proxies for the boundary are: 1) the base of the Arctoteuthis tehamaensis Zone in boreal and subboreal regions, 2) the dated base of the Alpina Subzone at 140.22 ±0.14 Ma, which also gives a precise age estimate for the system boundary; and 3) the base of radiolarian “unitary zone” 14, which is situated just above the base of the Alpina Subzone.
Published: 2020
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7. The proposal of a GSSP for the Berriasian Stage (Cretaceous System): Part 2

Author: Bruno Galbrun, Petr Schnabl, Chris Hunt, Terry P. Poulton, Petr Pruner, Daniela Reháková, Krýstina Šifnerová, Luc G. Bulot, William A.P. Wimbledon, Camille Frau, O. S. Dzyuba, Šimon Kdýr, Tiiu Elbra, Johann Schnyder, Lucie Vaňková, Andrea Svobodová, Alberto Carlos Riccardi, Philip Copestake, Luis Lena, School of Earth Sciences [Bristol], University of Bristol [Bristol], Institute of Geology of the Czech Academy of Sciences (GLI / CAS), Czech Academy of Sciences [Prague] (CAS), Groupement Interet Paleontologie Science & Exposition, Institut des Sciences de la Terre de Paris (iSTeP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Charles University [Prague] (CU), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Université de Genève = University of Geneva (UNIGE), Bulot, Luc, Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), and Université de Genève (UNIGE)
Subjects: 010506 paleontology, Biozone, Context (language use), Biostratigraphy, 010502 geochemistry & geophysics, 01 natural sciences, Cretaceous, Berriasian Stage, Sequence (geology), Paleontology, Stage (stratigraphy), [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDU.STU.GC] Sciences of the Universe [physics]/Earth Sciences/Geochemistry, QE, magnetostratigraphy, [SDU.STU.AG]Sciences of the Universe [physics]/Earth Sciences/Applied geology, Magnetostratigraphy, 0105 earth and related environmental sciences, GSSP, 15. Life on land, Global Boundary Stratotype Section and Point, Vocontian Basin, [SDU.STU.AG] Sciences of the Universe [physics]/Earth Sciences/Applied geology, [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, [SDU.STU.ST] Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, [SDU.STU.PG] Sciences of the Universe [physics]/Earth Sciences/Paleontology, biostratigraphy, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology, Geology
Abstract: International audience; In part 1 of this work we discussed the possibilities for the selection of a GSSP for the Berriasian Stage of the Cretaceous System, based on prevailing practical methods for correlation in that J/K interval, traditional usage and the consensus over the best boundary markers that had developed in the last forty years. This consensus has developed further, based on the results of multidisciplinary studies on numerous sites over the last decade. Here in Part 2 we give an account of the application of those results by the Berriasian Working Group (ISCS), and present the stratigraphic evidence that justifies the selection of the locality of Tré Maroua (Hautes-Alpes, SE France) as the proposed GSSP. We describe a 45 m-thick section in the Calcaires Blancs vocontiens – that part of the formation covering the calpionellid Chitinoidella, Remanei. Intermedia, Colomi, Alpina, Ferasini, Elliptica and Simplex biozones. The stratigraphic data collected here has been compiled as part of a wider comparative study of complementary Vocontian Basin sites (with localities at Charens, St Bertrand, Belvedere and Le Chouet). Evidence from Tré Maroua thus sits in this substantial regional biostratigraphic and magnetostratigraphic context. For the purposes of the GSSP definition, here we particularly concentrate on the unbroken sequence and biotic markers in the interval immediately below the boundary, the Colomi Subzone (covering circa 675,000 years), and immediately above, the Alpina Subzone (covering circa 725,000 years). Particularly significant fossil datums identified in the Tré Maroua profile are the primary basal Berriasian marker, the base of the Alpina Subzone (a widespread event marked by dominance of small Calpionella alpina, with rare Crassicollaria parvula and Tintinopsella carpathica): the base of the Berriasian Stage is placed at the base of bed 14, which coincides with the base of the Alpina Subzone. Secondary markers bracketing the base of the Calpionella Zone are the FOs of the calcareous nannofossil species Nannoconus wintereri, close below the boundary, and the FO of Nannoconus steinmannii minor, close above. The Tithonian/Berriasian boundary level occurs within M19n.2n, in common with many documented sites, and is just below the distinctive reversed magnetic subzone M19n.1r (the so-called Brodno reversal). We present data which is congruent with magnetostratigraphic and biostratigraphic data from other key localities in France and in wider regions (Le Chouet, Saint Bertrand, Puerto Escaño, Rio Argos, Bosso, Brodno, Kurovice, Theodosia…), and thus the characteristics and datums identified at Tré Maroua are key for correlation and, in general, they typify the J/K boundary interval in Tethys and connected seas.
Published: 2020

8. Carbon and silica megasink in deep-sea sediments of the Congo terminal lobes

Author: Martial Taillefert, Karine Olu, Mélanie Raimonet, Lucie Pastor, Jean-Louis Reyss, Olivier Ragueneau, Philippe Martinez, Laurence Méjanelle, Laurence Droz, P. Michalopoulos, Elsa Stetten, François Baudin, Christophe Rabouille, Bernard Dennielou, Audrey M. Pruski, Johann Schnyder, Julie Tourolle, Alexis Khripounoff, Livio Ruffine, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Océan et Interfaces (OCEANIS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Géosciences Marines (GM), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Institut des Sciences de la Terre de Paris (iSTeP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Géosciences Océan (LGO), Université de Bretagne Sud (UBS)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Environnement Profond (LEP), Etudes des Ecosystèmes Profonds (EEP), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Ecogéochimie des environnements benthiques (LECOB), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Observatoire océanologique de Banyuls (OOB), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Hellenic Centre for Marine Research (HCMR), Paléoenvironnemements Paléoclimats, Bassins (ISTEP-PPB), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), School of Earth and Atmospheric Sciences [Atlanta], Georgia Institute of Technology [Atlanta], ANR-11-BS56-0030,CONGOLOBE,Transfert de carbone organique et fonctionnement des écosystèmes dans les lobes terminaux de l'éventail sous-marin du Congo(2011), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Unité de recherche Géosciences Marines (Ifremer) (GM), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut Français de Recherche pour l'Exploitation de la Mer - Brest (IFREMER Centre de Bretagne), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), IFREMER- Département Etude des Ecosystèmes Profonds (DEEP/LEP), UMR 5805 Environnements et Paléoenvironnements Océaniques et Continentaux (EPOC), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS), Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Brest (UBO), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Conception, Optimisation et Modélisation des Systèmes (LCOMS), Université de Lorraine (UL), Institut de Recherche pour le Développement (IRD)-Institut Universitaire Européen de la Mer (IUEM), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Université de Brest (UBO)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Université Paris Diderot - Paris 7 (UPD7)-IPG PARIS-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: 010506 paleontology, Archeology, Biogeochemical cycle, 010504 meteorology & atmospheric sciences, Geochemistry, Sedimentology-marine cores, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Submarine canyon, 01 natural sciences, Deep sea, South Atlantic, Paleoceanography, Organic geochemistry, 14. Life underwater, Glacial period, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, Total organic carbon, Present, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Global and Planetary Change, geography, geography.geographical_feature_category, ACL, Geology, Last Glacial Maximum, 13. Climate action, Inorganic geochemistry, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract: International audience; Carbon and silicon cycles at the Earth surface are linked to long-term variations of atmospheric CO2 and oceanic primary production. In these cycles, the river-sea interface is considered a biogeochemical hotspot, and deltas presently receive and preserve a major fraction of riverine particles in shallow water sediments. In contrast, periods of glacial maximum lowstand were characterized by massive exports of sediments to the deep-sea via submarine canyons and accumulation in deep-sea fans. Here, we calculate present-day mass balances for organic carbon (OC) and amorphous silica (aSi) in the terminal lobe complex of the Congo River deep-sea fan as an analogue for glacial periods. We show that this lobe complex constitutes a megasink with the current accumulation of 18 and 35% of the OC and aSi river input, respectively. This increases the estimates of organic carbon burial by 19% in the South Atlantic Ocean in a zone representing less than 0.01% of the basin. These megasinks might have played a role in carbon trapping in oceanic sediments during glacial times.
Published: 2019
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9. Architecture and sedimentary evolution of the southwestern Gissar carbonate platform (Uzbekistan) during the Middle-Late Jurassic

Author: Pierre Pellenard, Christian Blanpied, Eric Barrier, Marie-Françoise Brunet, Raphaël Bourillot, Mehdi Carmeille, Johann Schnyder, Franz T. Fürsich, Irina Sidorova, Géoressources et environnement, Institut Polytechnique de Bordeaux (Bordeaux INP)-Université Bordeaux Montaigne, Institut des Sciences de la Terre de Paris (iSTeP), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS), Biogéosciences [UMR 6282] [Dijon] (BGS), Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique (CNRS), Fachgruppe PaläoUmwelt, GeoZentrum Nordbayern, Friedrich-Alexander Universität Erlangen-Nürnberg (FAU)-Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Institute of Geology and Geophysics, Academy of Sciences of Republic of Uzbekistan, Work funded by TOTAL., Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Friedrich-Alexander Universität Erlangen-Nürnberg (FAU)-GeoZentrum Nordbayern
Subjects: 010506 paleontology, Carbonate ramp and shelf, Sequence stratigraphy, Carbonate platform, Stratigraphy, 010502 geochemistry & geophysics, Oceanography, 01 natural sciences, chemistry.chemical_compound, Paleontology, 14. Life underwater, Tethys, Reef, 0105 earth and related environmental sciences, Sabkha, geography, Anhydrite, geography.geographical_feature_category, Middle-upper Jurassic, Carbon isotope stratigraphy, Amu Darya basin, Geology, 15. Life on land, Geophysics, chemistry, 13. Climate action, [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, Ooid, Facies, Economic Geology, Sedimentary rock, Progradation
Abstract: 29 pages; International audience; Sedimentological investigations have been carried out in the southwestern part of the Gissar Range (Uzbekistan) in order to document the stratigraphic evolution of a vast Middle–Upper Jurassic carbonate platform developed on the northern margin of the Amu Darya Basin. Two major sequences are distinguished, based on their contrasting facies pattern, platform configuration and carbon isotope signature: (1) a Callovian Sequence and (2) an Upper Jurassic Sequence, potentially Oxfordian to Kimmeridgian in age. A carbonate ramp with a double proximal-distal polarity developed during the Callovian Sequence. Oo-bioclastic grainstones were produced in two permanently agitated shallow water areas developing to the north and to the south. Patch and pinnacle reefs mainly built up close to the storm-wave base, passing distally to pellet- and foraminiferal-oncoid-rich mid-to outer-ramp deposits. The top of the Callovian Sequence is a regional discontinuity that could have formed by subaerial exposure of the platform. This probable hiatus could record a major climatic change associated to the Middle‒Late Jurassic transition. The Upper Jurassic Sequence consists of metre-thick alternations of pellet/algal-pack- to grainstones, microbial oncoid floatstones, ooid grainstones, and mudstones, which have likely accumulated in a vast lagoon protected by a large-scale barrier reef observed south of the study area. Gypsum and anhydrite content gradually increased towards the top of the Upper Jurassic Sequence, ending up with a thick chicken-wire gypsum accumulation recording the progradation of a large-scale sabkha over the lagoon. This phenomenon is related to a progressive aridification and restriction of the Amu Darya Basin that could have begun during the Middle/Late Oxfordian and reached its climax during the Tithonian with massive halite deposition. Comparable events occurred in Jurassic platforms located along the Tethyan margins, pointing to regional and global controls on sedimentation.
Published: 2018
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10. Fault imprint in clay units: Magnetic fabric, p-wave velocity, structural and mineralogical signatures

Author: Emeline Moubeche, Catherine Homberg, Eva Moreno, Pierre Dick, Alain Person, Arthur du Peloux, Christian David, Audrey Bonnelye, Johann Schnyder, Variabilité de l'Océan et de la Glace de mer (VOG), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre de Paris (iSTeP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Paul Scherrer Institute (PSI), Institut de Géologie et d'Hydrogéologie, Université de Neuchâtel (UNINE), CY Cergy Paris Université (CY), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire Géosciences et Environnement Cergy (GEC), Fédération INSTITUT DES MATÉRIAUX DE CERGY-PONTOISE (I-MAT), CY Cergy Paris Université (CY)-CY Cergy Paris Université (CY), Laboratoire d'Etude et de recherche sur les Transferts et les Installations dans les Sols (IRSN/PRP-DGE/SRTG/LETIS), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Institut de Recherche pour le Développement (IRD)-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Institut de Recherche pour le Développement (IRD)-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS), and PRP-DGE/SRTG/LETIS
Subjects: 010504 meteorology & atmospheric sciences, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Fault (geology), 010502 geochemistry & geophysics, 01 natural sciences, Strike-slip fault, Compression (geology), Petrology, Anisotropy, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Earth-Surface Processes, geography, geography.geographical_feature_category, Siderite, P-wave velocity, Petrophysics, Strike-slip tectonics, Tournemire, Clay minerals, Tectonics, Geophysics, Sinistral and dextral, Anisotropy of magnetic susceptibility, Fracture (geology), Geology
Abstract: International audience; We investigated the evolution of the structure, physical properties and fluid flow properties across a fault zone within the Toarcian shale formation from the Tournemire Underground Research Laboratory (France). With this purpose, an integrated approach was used based on the analysis of petrofabric (anisotropy of magnetic susceptibility, AMS, and of p-wave velocity, APV) and the mineralogy of two cores intercepting the F2 fault, a strike-slip fault with a small vertical offset.The fracture patterns indicated that the fault registered a multiphase tectonic evolution. Two strike-slip regimes, with approximate NE-SW and NW-SE compression, and a normal regime with a WNW-ESE direction of extension were identified. Most of the N-S fault planes collected in TF1 core, have a shallow dip with values between 5° to 45°. We further evidenced a close relationship between the fault architecture and petrophysical properties. A preferential NW-SE orientation of the K1 axes was observed that is in agreement with the extensional direction of the dextral movement of the fault. Within the fault core, an important decrease in anisotropy was observed and indicates clay platelets rotations related to tectonic deformation. A weaker anisotropic change was observed in ASM1. This difference may be related to the local variability of the fault zone and suggests the need to study the characteristics of a fault zone both across its different architectural zones and along the main fracture plan. Finally, we identified evidence of minerals alteration related to fault reactivation and fluid circulation. Fluid circulation enabled the transformation of siderite in magnetite, a neo-formation of kaolinite and a precipitation of calcite were at vicinity of the damage zone/fault core boundary. In TF1, while the major mineralogical changes occur in the damage zone. In ASM1, a higher illite-smectite mixed layers and calcite content was observed in the eastern side of the fault.
Published: 2018
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11. The brittle and ductile components of displacement along fault zones

Author: Vincent Roche, Johann Schnyder, Catherine Homberg, Véronique Léonardi, M. Benzaggagh, Institut des Sciences de la Terre de Paris (iSTeP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), University College of Dublin, University College Dublin [Dublin] (UCD), Hydrosciences Montpellier (HSM), Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université de Moulay Ismail (UMI), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and Université Moulay Ismail (UMI)
Subjects: Brittleness, 010504 meteorology & atmospheric sciences, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Geology, Ocean Engineering, Geotechnical engineering, Displacement (orthopedic surgery), 010502 geochemistry & geophysics, 01 natural sciences, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Water Science and Technology
Abstract: International audience
Published: 2017
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12. EFFECTS OF EARLY DIAGENESIS ON THE ISOTOPIC SIGNATURE OF WOOD: INCUBATIONS IN AQUATIC MICROCOSM

Author: Romain Tramoy, Thanh Thuy Nguyen Tu, Véronique Vaury, Mathieu Sebilo, Millot Cornette, L., Céline Roose-Amsaleg, Johann Schnyder, Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Milieux Environnementaux, Transferts et Interactions dans les hydrosystèmes et les Sols (METIS), Université Pierre et Marie Curie - Paris 6 (UPMC)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Institut d'écologie et des sciences de l'environnement de Paris (iEES), Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-École pratique des hautes études (EPHE)-Centre National de la Recherche Scientifique (CNRS), Institut d'écologie et des sciences de l'environnement de Paris (IEES), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Recherche Agronomique (INRA), Université Pierre et Marie Curie - Paris 6 (UPMC)-École pratique des hautes études (EPHE), and Tramoy, Romain
Subjects: [SDU.STU.CL] Sciences of the Universe [physics]/Earth Sciences/Climatology, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, [SDE.ES] Environmental Sciences/Environmental and Society, [SDE.ES]Environmental Sciences/Environmental and Society, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2017

13. The Congolobe project, a multidisciplinary study of Congo deep-sea fan lobe complex: Overview of methods, strategies, observations and sampling

Author: Nicolas Gayet, Karine Charlier, Mélanie Raimonet, Olivier Ragueneau, Philippe Noel, J. Le Saout, Christophe Rabouille, Florence Savignac, Laurent Toffin, Gilles Vétion, Ming-Yi Sun, Lucie Pastor, Perrine Cruaud, S. Bourgeois, Anne Godfroy, Françoise Lesongeur, F. Toussaint, Julie Tourolle, François Baudin, Olivier Mouchel, Elsa Stetten, Philippe Rodier, Audrey M. Pruski, Martine Bez, Cecile Cathalot, Martial Taillefert, Sophie Arnaud-Haond, Lara Pozzato, Rudolph Corvaisier, Laurence Méjanelle, N. Tisnerat-Laborde, Claire Croguennec, Christophe Brandily, Philippe Martinez, Jean-Claude Caprais, Arunima Sen, Bernard Dennielou, Bruno Bombled, Sandrine Bessette, C. Senyarich, Alexis Khripounoff, Karine Olu, Laurence Droz, M. Lesaout, Marie Picot, Stéphane Hourdez, Jordon S. Beckler, J. Le Bruchec, Johann Schnyder, Patricia Pignet, Nathalie Babonneau, Livio Ruffine, M. Rabiller, J.L. Reyss, P. Michalopoulos, J.-M. Jouanneau, C. Bayle, Carole Decker, Sara Teixeira, B. Ruesch, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Océan et Interfaces (OCEANIS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Laboratoire Environnement Profond (LEP), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Evolution et Modélisation des Bassins Sédimentaires (EMBS), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS), Unité de recherche Géosciences Marines (Ifremer) (GM), Laboratoire de microbiologie des environnements extrêmophiles (LM2E), Centre National de la Recherche Scientifique (CNRS)-Université de Brest (UBO)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Domaines Océaniques (LDO), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Observatoire des Sciences de l'Univers-Institut d'écologie et environnement-Centre National de la Recherche Scientifique (CNRS), School of Earth and Atmospheric Sciences [Atlanta], Georgia Institute of Technology [Atlanta], Laboratoire d'Ecogéochimie des environnements benthiques (LECOB), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Observatoire océanologique de Banyuls (OOB), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), UMR 5805 Environnements et Paléoenvironnements Océaniques et Continentaux (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Brest (UBO), Adaptation et Biologie des Invertébrés en Conditions Extrêmes (ABICE), Adaptation et diversité en milieu marin (AD2M), Station biologique de Roscoff (SBR), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Station biologique de Roscoff (SBR), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Hellenic Centre for Marine Research (HCMR), Department of Marine Sciences [Athens], University of Georgia [USA], Centre of Marine Sciences [Faro] (CCMAR), University of Algarve [Portugal], Géochrononologie Traceurs Archéométrie (GEOTRAC), TOTAL-Scientific and Technical Center Jean Féger (CSTJF), TOTAL FINA ELF, ANR-11-BS56-0030,CONGOLOBE,Transfert de carbone organique et fonctionnement des écosystèmes dans les lobes terminaux de l'éventail sous-marin du Congo(2011), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Etudes des Ecosystèmes Profonds (EEP), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Géosciences Marines (GM), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), Environnements et Paléoenvironnements OCéaniques (EPOC), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Adaptation et diversité en milieu marin (ADMM), Institut national des sciences de l'Univers (INSU - CNRS)-Station biologique de Roscoff (SBR), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Station biologique de Roscoff (SBR), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre scientifique et Technique Jean Feger (CSTJF), and Centre National de la Recherche Scientifique (CNRS)-Institut d'écologie et environnement-Observatoire des Sciences de l'Univers-Université de Brest (UBO)-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: Turbidity current, Continental-Margin, 010504 meteorology & atmospheric sciences, Fine sediment, Sedimentation rate, Transport, Submarine canyon, Vesicomyidae, 010502 geochemistry & geophysics, Oceanography, Turbidite, 01 natural sciences, Deep sea, Particulate Materials, Guaymas Basin, 14. Life underwater, Congo deep-sea fan, Chemosynthetic habitats, Turbidity-Current, 0105 earth and related environmental sciences, Canyon, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, geography, geography.geographical_feature_category, ACL, Organic-Carbon Accumulation, Particle Fluxes, Estuary, Seafloor morphology, 15. Life on land, M Water Depth, 13. Climate action, Mud Volcano, [SDE]Environmental Sciences, Chemosynthetic Ecosystems, Submarine pipeline, Sedimentary rock, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Geology
Abstract: The presently active region of the Congo deep-sea fan (around 330,000 km(2)), called the terminal lobes or lobe complex, covers an area of 2500 km(2) at 4700-5100 m water depth and 750-800 km offshore. It is a unique sedimentary area in the world ocean fed by a submarine canyon and a channel-levee system which presently deliver large amounts of organic carbon originating from the Congo River by turbidity currents. This particularity is due to the deep incision of the shelf by the Congo canyon, up to 30 km into the estuary, which funnels the Congo River sediments into the deep-sea. The connection between the river and the canyon is unique for major world rivers. In 2011, two cruises (WACS leg 2 and Congolobe) were conducted to simultaneously investigate the geology, organic and inorganic geochemistry, and micro- and macro-biology of the terminal lobes of the Congo deep-sea fan. Using this multidisciplinary approach, the morpho-sedimentary features of the lobes were characterized along with the origin and reactivity of organic matter, the recycling and burial of biogenic compounds, the diversity and function of bacterial and archaeal communities within the sediment, and the biodiversity and functioning of the faunal assemblages on the seafloor. Six different sites were selected for this study: Four distributed along the active channel from the lobe complex entrance to the outer rim of the sediment deposition zone, and two positioned cross-axis and at increasing distance from the active channel, thus providing a gradient in turbidite particle delivery and sediment age. This paper aims to provide the general context of this multidisciplinary study. It describes the general features of the site and the overall sampling strategy and provides the initial habitat observations to guide the other in-depth investigations presented in this special issue. Detailed bathymetry of each sampling site using 0.1-1 m resolution multibeam obtained with a remotely operated vehicle (ROV) shows progressive widening and smoothing of the channel-levees with increasing depth and reveals a complex morphology with channel bifurcations, erosional features and massive deposits. Dense ecosystems surveyed in the study area gather high density clusters of two large-sized species of symbiotic Vesicomyidae bivalves and microbial mats. These assemblages, which are rarely observed in sedimentary zones, resemble those based on chemosynthesis at cold-seep sites, such as the active pockmarks encountered along the Congo margin, and share with these sites the dominant vesicomyid species Christineconcha regab. Sedimentation rates estimated in the lobe complex range between 0.5 and 10 cm yr(-1), which is 2-3 orders of magnitude higher than values generally encountered at abyssal depths. The bathymetry, faunal assemblages and sedimentation rates make the Congo lobe complex a highly peculiar deep-sea habitat driven by high inputs of terrigenous material delivered by the Congo channel-levee system. (c) 2016 Elsevier Ltd. All rights reserved. ZAIANGO ANR Congolobe (ANR Blanc SIMI5-6) [11 BS56 030] IFREMER CEA through LSCE U.S. National Science Foundation [OCE-0831156] info:eu-repo/semantics/acceptedVersion
Published: 2017
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14. Palynofacies reveal fresh terrestrial organic matter inputs in the terminal lobes of the Congo deep-sea fan

Author: Elsa Stetten, François Baudin, Johann Schnyder, Audrey M. Pruski, Philippe Martinez, Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Ecogéochimie des environnements benthiques (LECOB), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Observatoire océanologique de Banyuls (OOB), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE)
Subjects: Turbidity current, 010504 meteorology & atmospheric sciences, Submarine canyon, 010502 geochemistry & geophysics, Oceanography, 01 natural sciences, Deep sea, Paleontology, Organic matter, 14. Life underwater, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, chemistry.chemical_classification, Chemosynthesis, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, geography, geography.geographical_feature_category, 15. Life on land, Palynofacies, chemistry, [SDU]Sciences of the Universe [physics], [SDE]Environmental Sciences, Submarine pipeline, Channel (geography), Geology
Abstract: The Congo deep-sea fan is directly connected to the Congo River by a unique submarine canyon. The Congo River delivers up to 2×1012gPOC/yr, a part of which is funnelled by the submarine canyon and feeds the deep-sea environments. The more distal part of the Congo deep-sea fan, the terminal lobe area, has a surface of 2500 km2 and is situated up to 800 km offshore at depths of 4750–5000 m. It is a remarkable place to study the fate and distribution of the organic matter transferred from the continent to the deep ocean via turbidity currents. Forty-two samples were analyzed from the terminal lobes, including sites from the active channel, one of its levees and an abandoned distal channel. Samples were collected using multitube cores and push-cores using a Victor 6000 ROV, which surveyed the dense chemosynthetic habitats that locally characterize the terminal lobes. Palynofacies reveal a remarkably well-preserved, dominantly terrestrial particulate organic matter assemblage, that has been transferred from the continent into the deep-sea by turbidity currents. Delicate plant structures, cuticle fragments and plant cellular material is often preserved, highlighting the efficiency of turbidity currents to transfer terrestrial organic matter to the sea-floor, where it is preserved. Moreover, the palynofacies data reveal a general sorting by density or buoyancy of the organic particles, as the turbulent currents escaped the active channel, feeding the levees and the more distal, abandoned channel area. Finally, in addition to aforementioned hydrodynamic factors controlling the organic matter accumulation, a secondary influence of chemosynthetic habitats on organic matter preservation is also apparent. Palynofacies is therefore a useful tool to record the distribution of organic matter in recent and ancient deep-sea fan environments, an important topic for both academic and petroleum studies.
Published: 2017
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15. Subtropical climate conditions and mangrove growth in Arctic Siberia during the early Eocene

Author: Daichi Yoon, Séverine Fauquette, Jean-Pierre Suc, Guillaume Suan, François Baudin, Nikolay N. Sobolev, Speranta-Maria Popescu, Johann Schnyder, Loïc Labrousse, Karsten Piepjohn, 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), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), PaleoEnvironnements et PaleobioSphere (PEPS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UR226, Paléobiodiversité et paléoenvironnements, Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire de tectonique (LT), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), 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), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique (CNRS), and Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, biology, Coastal plain, Humid subtropical climate, Geology, Subtropics, 15. Life on land, 010502 geochemistry & geophysics, biology.organism_classification, 01 natural sciences, Avicennia, Oceanography, Arctic, 13. Climate action, [SDU]Sciences of the Universe [physics], Climate model, Precipitation, Polar climate, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: The early Eocene (ca. 56–47.8 Ma) was an interval of exceptional warmth with reduced pole-to-equator temperature gradients. Climate proxies indicate mean annual air temperatures (MATs) and sea-surface temperatures (SSTs) exceeding 8–18 °C and frost-free, mild winters in polar areas, features that have proven difficult to reproduce with the most elaborate climate models. A full appraisal of the early Eocene polar climate has been, however, limited by possible seasonal biases associated with geochemical proxies and the lack of data from the vast Eurasian Arctic. Here we present multiproxy data from lower-middle Eocene coastal plain sediments of the New Siberian Islands (Russia) showing that taxodioid Cupressaceae, palms, and the mangrove Avicennia grew in Arctic Siberia above 72°N under air temperatures averaging 16–21 °C annually and 5.5–14 °C in winter. Kaolinite contents are exceptionally high (up to 60% of clay assemblages) and comparable to those found in present-day subtropical soils formed under high mean annual precipitation (MAP >1000 mm) and warm (MAT >15 °C) conditions. The Avicennia pollen records the northernmost mangrove growth ever documented and indicates early Eocene SSTs exceeding 13 °C in winter and 18 °C in summer. Considering the high MAP estimated for Arctic Siberia and other pan-Arctic landmasses, we propose that the heat from warm river waters draining into the Arctic might have amplified early Eocene polar warmth. Our results provide the first climate constraints for the early Eocene of Arctic Siberia and support the view that most climate models underestimate polar warming in greenhouse conditions.
Published: 2017
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16. Palaeoenvironmental control on primary fluids characteristics of lacustrine source rocks in the Autun Permian Basin (France)

Author: Sylvain Garel, François Baudin, Françoise Behar, Johann Schnyder, Institut des Sciences de la Terre de Paris (iSTeP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Total E&P, TOTAL S.A., TOTAL FINA ELF, Evolution et Modélisation des Bassins Sédimentaires (EMBS), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: lacustrine environment, 010504 meteorology & atmospheric sciences, Geochemistry, Botryococcus, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, organic geochemistry, boghead, 010502 geochemistry & geophysics, 01 natural sciences, Paleontology, chemistry.chemical_compound, Water column, Algae, Organic geochemistry, Kerogen, Type I kerogen, 0105 earth and related environmental sciences, biology, lcsh:QE1-996.5, Geology, oil-shale, biology.organism_classification, Anoxic waters, Palynofacies, lcsh:Geology, Source rock, chemistry, primary fluids
Abstract: International audience; The Autunian (Late Gzhelian-Sakmarian, ∼295 Ma) of the Autun Basin (Saône-et-Loire, France) is well known for its lacustrine oil-shales and boghead that were exploited during the 19th and 20th centuries. A study of the kerogen geochemistry, palynofacies, hydrocarbon (HC) distribution of pyrolysates and kinetics on these organic-rich sediments gave indications on the control of lacustrine primary fluid characteristics by palaeoenvironmental settings. Palynofacies results have shown a Botryococcus algae dominance in the boghead, whereas the oil-shales were dominated either by a mixing of terrestrial particles and lacustrine phytoplanktonic/bacterial organic matter (OM), or by a lacustrine OM that suffered biodegradation within the water column. During the Autunian, an increasing trend of degraded lacustrine OM concentration is observed in the successive oil-shales. Geochemical and kinetics analyses showed that, except for the boghead, hydrogen index values were
Published: 2017
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17. Origin and distribution of the organic matter in the distal lobe of the Congo deep-sea fan – A Rock-Eval survey

Author: Elsa Stetten, Karine Charlier, François Baudin, Laurence Droz, Johann Schnyder, Bernard Dennielou, Philippe Martinez, Evolution et Modélisation des Bassins Sédimentaires (EMBS), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), UMR 5805 Environnements et Paléoenvironnements Océaniques et Continentaux (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Unité de recherche Géosciences Marines (Ifremer) (GM), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Domaines Océaniques (LDO), Centre National de la Recherche Scientifique (CNRS)-Institut d'écologie et environnement-Observatoire des Sciences de l'Univers-Université de Brest (UBO)-Institut national des sciences de l'Univers (INSU - CNRS), ANR-11-BS56-0030,CONGOLOBE,Transfert de carbone organique et fonctionnement des écosystèmes dans les lobes terminaux de l'éventail sous-marin du Congo(2011), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Observatoire des Sciences de l'Univers-Institut d'écologie et environnement-Centre National de la Recherche Scientifique (CNRS), Environnements et Paléoenvironnements OCéaniques (EPOC), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE), and Géosciences Marines (GM)
Subjects: 010504 meteorology & atmospheric sciences, Submarine canyon, 010502 geochemistry & geophysics, Oceanography, 01 natural sciences, Deep sea, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Recent sediments, Organic matter, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, organic matter, Total organic carbon, Canyon, chemistry.chemical_classification, geography, geography.geographical_feature_category, Soil organic matter, Sediment, Rock-Eval pyrolysis, 15. Life on land, 6. Clean water, chemistry, recent sediments, [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, Congo turbidite system, Sedimentary rock, Geology
Abstract: International audience; The Congo River, the second largest river in the world, is a major source of organic matter for the deep Atlantic Ocean because of the connection of its estuary to the deep offshore area by a submarine canyon which feeds a vast deep-sea fan. The lobe zone of this deep-sea fan is the final receptacle of the sedimentary inputs presently channelled by the canyon and covers an area of ~2500 km². The quantity and the source of organic matter preserved in recent turbiditic sediments from the distal lobe of the Congo deep-sea fan were assessed using Rock-Eval pyrolysis analyses. Six sites, located at approximately 5000 m water-depth, were investigated. The mud-rich sediments of the distal lobe contain high amounts of organic matter (~3.5 to 4% Corg), the origin of which is a mixture of terrestrial higher-plant debris, soil organic matter and deeply oxidized phytoplanktonic material. Although the respective contribution of terrestrial and marine sources of organic matter cannot be precisely quantified using Rock-Eval analyses, the terrestrial fraction is dominant according to similar hydrogen and oxygen indices of both suspended and bedload sediments from the Congo River and that deposited in the lobe complex. The Rock-Eval signature supports the 70% to 80% of the terrestrial fraction previously estimated using C/N and δ13Corg data. In the background sediment, the organic matter distribution is homogeneous at different scales, from a single turbiditic event to the entire lobe, and changes in accumulation rates only have a limited effect on the quantity and quality of the preserved organic matter. Peculiar areas with chemosynthetic bivalves and/or bacterial mats, explored using ROV Victor 6000, show a Rock-Eval signature more or less similar to background sediment. This high organic carbon content associated to high sedimentation rates (> 2 to 20 mm.yr−1) in the Congo distal lobe complex implies a high burial rate for organic carbon. Consequently, the Congo deep-sea fan represents an enormous sink of terrestrial organic matter when compared to other turbiditic systems over the world.
Published: 2017
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18. Late Jurassic dinosaur footprints from Chassiron–La Morelière (Oléron Island, western France)

Author: Didier Néraudeau, Romain Vullo, Johann Schnyder, Bastien Mennecart, Dominique Abit, Jean-David Moreau, Biogéosciences [Dijon] ( BGS ), Université de Bourgogne ( UB ) -AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique ( CNRS ), Géosciences Rennes ( GR ), Université de Rennes 1 ( UR1 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Observatoire des Sciences de l'Univers de Rennes ( OSUR ) -Centre National de la Recherche Scientifique ( CNRS ), Naturhistorisches Museum Basel, Evolution et Modélisation des Bassins Sédimentaires ( EMBS ), Institut des Sciences de la Terre de Paris ( iSTeP ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ), Biogéosciences [UMR 6282] (BGS), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Géosciences Rennes (GR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Evolution et Modélisation des Bassins Sédimentaires (EMBS), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Association Dinoléron, Biogéosciences [UMR 6282] [Dijon] (BGS), Centre National de la Recherche Scientifique (CNRS)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement, Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 1 (UR1), and Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)
Subjects: 010506 paleontology, Dinosaur footprints, Late Jurassic, Context (language use), Trace fossil, Structural basin, 010502 geochemistry & geophysics, 01 natural sciences, chemistry.chemical_compound, Paleontology, Oléron Island (France), Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, [ SDU.STU.PG ] Sciences of the Universe [physics]/Earth Sciences/Paleontology, Calcite, Ripple marks, Global and Planetary Change, Ecology, Theropods, Geology, Trackway, White-light scanner, Sauropods, chemistry, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology, Tidal flat
Abstract: International audience; A new dinosaur tracksite was recently discovered in the Upper Jurassic deposits from the Oléron Island (Atlantic Ocean, western France). Tracks are located along the coastline in the tidal area of La Morelière near “Pointe de Chassiron”. They were observed in situ in an evaporitic interval from the “Purbeck beds” Unit. Sediments consist of calcite recrystallised after gypsum dissolution within limestone layers which are composed of thin laminites. The track-bearing surface shows abundant mud cracks and some ripple marks. Ichnofossils consist of medium-sized tridactyl footprints of theropods forming a narrow trackway. In order to obtain 3D reconstructions of the track-bearing surface, the trackway was scanned with a resolution of 0.5 mm using an Artec Eva 3D white-light scanner. As indicated by the track dimensions, the probable trackmaker is assigned to a medium-sized non-coelurosaur tetanuran, such as a megalosauroid or an allosauroid theropod. The palaeoenvironmental context is interpreted as a tidal flat in an evaporitic basin. In addition to the tridactyl tracks, we report sauropod- and thyreophoran-like tracks on two other surfaces from Chassiron–La Morelière.
Published: 2017
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19. Stepwise palaeoclimate change across the Eocene–Oligocene transition recorded in continental NW Europe by mineralogical assemblages and d 15 N org (Rennes Basin, France)

Author: Marie Salpin, Hugues Bauer, Johan Yans, Véronique Vaury, Johann Schnyder, Mathieu Sebilo, Jérôme Fozzani, Romain Tramoy, Alain Person, Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Evolution et Modélisation des Bassins Sédimentaires (EMBS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institut d'écologie et des sciences de l'environnement de Paris (iEES), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Recherche Agronomique (INRA), Facultés Universitaires Notre Dame de la Paix (FUNDP), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Institut d'écologie et des sciences de l'environnement de Paris (IEES), and Facultés Universitaires Notre Dame de la Paix (FUNDP) - Namur
Subjects: 010504 meteorology & atmospheric sciences, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Geology, 15. Life on land, Structural basin, 010502 geochemistry & geophysics, 01 natural sciences, Isotopes of nitrogen, Paleontology, 13. Climate action, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, Period (geology), 14. Life underwater, Clay minerals, Global cooling, Cenozoic, 0105 earth and related environmental sciences
Abstract: International audience; The Eocene–Oligocene transition (EOT, ~34 Ma) is the largest global cooling of the Cenozoic Era and led the Earth's climatic system to change from a greenhouse to an icehouse mode. Although it is well documented in marine settings, the few studies focusing on continental environments have demonstrated regional heterogeneities. The study core CDB1, located in the Rennes Basin (Western France), is a unique terrestrial (lacustrine–palustrine) record comprising well-preserved and terrestrial-derived organic-rich sediments encompassing the EOT. Clay minerals and the first organic nitrogen isotope record (d 15 N org) of terrestrial origin for this period are used to reconstruct palaeoclimate changes across this key interval. As suggested in worldwide marine and a few continental records, a stepwise transition from warm/humid conditions in the Late Eocene to cooler/drier conditions in the Early Oligocene is confirmed in the area. In addition, an episode of drier conditions in the Late Eocene and humid/dry cycles in the Early Oligocene are suggested. Terra Nova, 00: 1–9, 2016
Published: 2016
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20. Carbon-isotope analysis of fossil wood and dispersed organic matter from the terrestrial Wealden facies of Hautrage (Mons Basin, Belgium)

Author: Jean-Yves Storme, Jean Dejax, Philippe Gerrienne, Paul Spagna, Johan Yans, Edouard Keppens, Thomas Gerards, Johann Schnyder, Fondation Universitaire Notre Dame de la Paix (FUNDP), Facultés Universitaires Notre Dame de la Paix (FUNDP), Paléobotanique, Paléopalynologie et Micropaléontologie, Université de Liège, Service de Géologie Fondamentale et Appliquée, Faculté polytechnique de Mons, Université de Mons (UMons)-Université de Mons (UMons), Département Histoire de la Terre, Muséum national d'Histoire naturelle (MNHN), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Earth System Sciences, and Vrije Universiteit Brussel (VUB)
Subjects: Delta, Carbon-isotope, 010506 paleontology, Aptian, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Early Cretaceous, Fossil wood, 010502 geochemistry & geophysics, Oceanography, 01 natural sciences, Paleontology, Belgium, Chemostratigraphy, Charcoal, Ecology, Evolution, Behavior and Systematics, ComputingMilieux_MISCELLANEOUS, Mons Basin, Wealden facies, 0105 earth and related environmental sciences, Earth-Surface Processes, Total organic carbon, 15. Life on land, Diagenesis, Alluvial plain, 13. Climate action, visual_art, visual_art.visual_art_medium, Geology
Abstract: Pedogenic nodules, calcitic shells, dispersed organic carbon and bulk rocks affected by low diagenesis are judged to be reliable tools for carbon-isotope chemostratigraphy. Up to now no systematic study has been carried out to check the reliability of fossil wood material for carbon-isotope chemostratigraphy in terrestrial settings. The 235-m thick Wealden facies sediments of the Danube-Bouchon quarry at Hautrage (Hautrage Clays Formation, Mons Basin, Belgium) encompass dark to grey clays and sands, rich in organic matter and coalified-charcoalified fragments of fossil wood, deposited in an alluvial plain during middle Barremian to earliest Aptian. We measured and compared the carbon-isotope ratios of 110 levels of the stratigraphic succession for dispersed organic carbon (δ13CDOC), and fossil wood (δ13CWOOD) collected in the same geological level. In the whole succession, the averages of δ13CDOC and δ13CWOOD have a significant difference of about 0.9‰. The δ13CWOOD is usually heavier than the δ13CDOC, which is consistent with measurements on different constituents of modern trees (branches versus leaves and tissues). In one single stratigraphic level, the variability of δ13CWOOD is much higher (up to 7.3‰) than that of δ13CDOC (0.4‰). Four main causes may explain these results. Firstly, the δ13CDOC averages the isotopic signal of different compounds and tissues (such as leaves, seeds, cuticles) as they become mixed and dispersed. The δ13CWOOD reflects the carbon-isotope ratio of a small part only of one single tree, which is a complex system with δ13C variations over a range of 4‰. Secondly, there is strong δ13C variability between different species of plants. In Hautrage, several gymnosperm genera were collected (including Podocarpoxylon, Taxodioxylon, Brachyoxylon, and Thujoxylon) and numerous fern taxa. Thirdly, coalification and charcoalification can affect the δ13C of the DOC and the various kinds of woods in a different way. Fourthly, the wood fragments may be reworked several times from more ancient geological levels, especially in the alluvial plain environment of Hautrage where thick levels of fluviatile coarse sand deposits are observed. However, in the whole succession, both δ13CWOOD and δ13CDOC curves show similar trends. This suggests that carbon-isotope curves on fossil wood can be matched to carbon-isotope curves on DOC. For the whole trend fossil wood is a relatively good chemostratigraphic tool when sufficient samples are measured in the succession. Whenever possible both control of the wood taxa, and estimation of degree of (char)coalification are however recommended. In one single level, charcoal has more stable δ13CWOOD values than δ13CWOOD of coalified fragments. The δ13C positive trend can be due to several causes, including global pCO2 variations and/or regional changes and/or local environmental conditions in the alluvial plain. If global, the dating of the Hautrage succession may be refined to the late Early Barremian-early Late Barremian by matching palynological and carbon-isotope chemostratigraphical data. © 2010 Elsevier B.V. All rights reserved.
Published: 2010
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21. The Pliensbachian-Toarcian paleoclimate transition: New insights from organic geochemistry and C, H, N isotopes in a continental section from Central Asia

Author: François Baudin, Denise Pons, Arnaud Huguet, Marc Philippe, Sylvie Derenne, Romain Tramoy, Mathieu Sebilo, Johan Yans, Jérémy Jacob, Johann Schnyder, T. T. Nguyen Tu, Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Evolution et Modélisation des Bassins Sédimentaires (EMBS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Milieux Environnementaux, Transferts et Interactions dans les hydrosystèmes et les Sols (METIS), Université Pierre et Marie Curie - Paris 6 (UPMC)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Facultés Universitaires Notre Dame de la Paix (FUNDP), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Biogéosystèmes Continentaux - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut d'écologie et des sciences de l'environnement de Paris (iEES), Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Ecologie des Hydrosystèmes Naturels et Anthropisés (LEHNA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École Nationale des Travaux Publics de l'État (ENTPE)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur la Paléobiodiversité et les Paléoenvironnements (CR2P), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), EMERGENCE 2012 project from the UPMC, DARIUS program in the framework of a collaboration with KAZNTU, Almaty, ANR-10-JCJC-0607,PalHydroMil,Reconstructions paléohydrologiques à partir du dD de lipides produits par les végétaux supérieurs. Calibration, validation et application aux variations hydrologiques dans les Alpes pendant l'âge du Bronze(2010), Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université Pierre et Marie Curie - Paris 6 (UPMC), Facultés Universitaires Notre Dame de la Paix (FUNDP) - Namur, Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut d'écologie et des sciences de l'environnement de Paris (IEES), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Recherche Agronomique (INRA), Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École Nationale des Travaux Publics de l'État (ENTPE), Systèmes d'élevage, nutrition animale et humaine (SENAH), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Université Pierre et Marie Curie - Paris 6 (UPMC)-École Pratique des Hautes Études (EPHE), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC)
Subjects: 010504 meteorology & atmospheric sciences, Climate change, Xenoxylon, 010502 geochemistry & geophysics, Oceanography, 01 natural sciences, GEOF, δ2H, Paleontology, n-Alkanes, Paleoclimatology, Organic geochemistry, medicine, Temperate climate, δ15Norg, δH, Organic matter, brGDGT, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, Earth-Surface Processes, chemistry.chemical_classification, δN, 15. Life on land, Seasonality, medicine.disease, Isotopes of nitrogen, chemistry, 13. Climate action, Period (geology), [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Geology
Abstract: The Taskomirsay section (South Kazakhstan) is a unique Pliensbachian-Toarcian sequence of lignites, clayey layers and silty-sandstones deposited in a fluvial/lacustrine environment with nearby swampy areas. This period, characterized by a drastic climate change, has been particularly studied in Western Tethyan marine environments, whereas very few studies focused on continental settings. Paleoflora analyses, associated with a multi-isotope approach, based on well-preserved Type-III bulk organic nitrogen isotopes (δ15Norg) and hydrogen isotopic composition (δ2H) of n-alkanes, were developed to document paleoclimatic changes in the area. Sporomorph associations and fossil woods revealed a globally warm- to cool-temperate climate – characterized by Xenoxylon, a conifer morphogenus biogeographically related to cool/humid settings – apart from slightly less humid and warmer conditions in the early Toarcian. Warmer conditions are supported by reconstructed Mean Annual Air Temperatures (MAATs), based on the first branched glycerol dialkyl glycerol tetraethers (brGDGTs) ever recorded in the Early Jurassic. Nevertheless, no drastic changes were recorded in the δ15Norg values; its signal being attributed to tenuous equilibrium between water- and nutrient-availability via intense N-recycling. Based on n-alkane distributions, sources of organic matter were separated in two pools: (i) a purely terrestrial (n-C27) and (ii) an “aquatic” pool (n-C23) constituted of vegetation that thrived under almost permanent water supply. The n-alkane δ2H values (− 248 to − 151‰) as well as their amounts and average chain lengths (ACL) are in agreement with cool-temperate conditions in the Pliensbachian and less humid/warmer conditions in the early Toarcian. The isotopic difference between δ2H values of n-C27 and n-C23 (Δ2Hter-aq) suggests enhanced seasonality during the Pliensbachian-Toarcian transition and low seasonality in the early Toarcian, in agreement with temperate climate-regime. Finally, contrasted response to paleoclimate changes between markers suggests different spatial integration of those proxies. The role of sea-level variations for δ2H values might also resolve this contrasted response.
Published: 2016
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22. Organic matter characterization and distribution in sediments of the terminal lobes of the Congo deep-sea fan: Evidence for the direct influence of the Congo River

Author: Christophe Rabouille, Karine Charlier, Philippe Martinez, Bernard Dennielou, Audrey M. Pruski, Elsa Stetten, Johann Schnyder, Jennifer Coston-Guarini, François Baudin, Jean-Louis Reyss, Institut des Sciences de la Terre de Paris (iSTeP), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS), Laboratoire d'Ecogéochimie des environnements benthiques (LECOB), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Observatoire océanologique de Banyuls (OOB), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Océan et Interfaces (OCEANIS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Unité de recherche Géosciences Marines (Ifremer) (GM), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Institut Français de Recherche pour l'Exploitation de la Mer - Brest (IFREMER Centre de Bretagne), Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Brest (UBO), ANR-11-BS56-0030,CONGOLOBE,Transfert de carbone organique et fonctionnement des écosystèmes dans les lobes terminaux de l'éventail sous-marin du Congo(2011), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE), Géosciences Marines (GM), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Turbidity current, Terrestrial organic matter, Submarine canyon, Oceanography, Deep sea, Geochemistry and Petrology, River mouth, Organic matter, Recent lobe complex, 14. Life underwater, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, chemistry.chemical_classification, Total organic carbon, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Congo River, geography, geography.geographical_feature_category, Continental shelf, ACL, Turbiditic system, Geology, 15. Life on land, Preservation, Palynofacies, chemistry, 13. Climate action, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract: International audience; The terminal lobe complex of the Congo River submarine fan sits on the abyssal Atlantic plain, at 5000 m water depth, 760 km offshore from the river mouth estuarine area. While most rivers deliver particulate material to the continental shelf, particulate matter from the Congo River largely bypasses the shelf and is transported by turbidity currents through the Congo submarine canyon system. We determined the quantity and quality of the organic matter reaching the terminal lobe complex at five sites with marked morphological differences that may influence the distribution of organic matter. A suite of bulk geochemical (% OC, δ13Corg, δ15N, C: N), 137Cs and palynofacies analyses were done on cores collected from the terminal lobe area. These results were also compared to the composition of sediments collected upstream at the Malebo Pool (Congo River).Distal lobe complex sediments contain high amounts of terrestrial organic carbon (3–5 wt.%) that is homogeneously distributed in surficial (22 cm) and deeper sediments (580 cm) silty–clay facies. Strongly altered soil-derived organic matter with well-preserved land plant detritus from the Congo River predominates. A terrestrial soil origin for the particulate load was confirmed by the elevated 137Cs activity in lobe sediments. The vertical distribution of the 137Cs signal suggests that there has been a massive arrival of terrestrial sediments since 1963, consistent with a turbiditic origin. From the locations surveyed, we estimate a maximum accumulation of terrestrial organic carbon of ca. 1 kg OC m− 2 y− 1 for the distal lobe. However, transport modifies the organic matter both in terms of quantity and quality. Observed differences were attributed to preferential degradation of nitrogenous matter during diagenesis and to the addition of highly remineralized marine organic matter.Results from our temporal reference site (E) suggest that organic matter may be preserved in turbidite facies for thousands of years. The good preservation state of the accumulated organic matter shows that turbiditic lobe complexes should be considered as a sink for terrestrial organic carbon in the deep ocean.
Published: 2015
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23. Timing of sea level, tectonics and climate events during the uppermost Oxfordian (Planula zone) on the Iberian ramp (northeast Spain)

Author: Claude Colombié, Marcos Aurell, Annette E. Götz, Myriam Boussaha, Beatriz Bádenas, Fabienne Giraud, Johann Schnyder, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), MAIF Foundation, UMR CNRS 5276 LGL-TPE of the University Lyon 1, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and 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)
Subjects: Micropalaeontology, Sequence stratigraphy, Micropaleontology, Cyclostratigraphy, Paleontology, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Sedimentology, Oceanography, Cretaceous, Palynofacies, Clay minerals, 13. Climate action, Facies, Siliciclastic, 14. Life underwater, Late Oxfordian, Ecology, Evolution, Behavior and Systematics, Geology, Sea level, Earth-Surface Processes
Abstract: International audience; The middle Oxfordian warming climate and sea-level rise initiated the development of vast carbonate platforms in some western European basins. At the same time, however, siliciclastics and siliceous sponges dominated certain marginal areas of the Iberian ramp. There, siliciclastic input was particularly prominent during the latest Oxfordian and may have been related to a global sea-level fall, synsedimentary tectonic activity, or humid climatic conditions in the hinterland. Field analyses and computer modelling have been previously used to determine the factors that controlled sedimentation. However, it is still unclear if the specific conditions that prevailed during the latest Oxfordian were due to eustasy, tectonics or climate, and when precisely they occurred. Here, we document major changes in sedimentological, micropalaeontological, and mineralogical records on the Iberian ramp during this interval. Detailed sedimentary facies and palynofacies analyses combined with sequence-stratigraphic and cyclostratigraphic analyses of the Ricla Barranco section enable the establishment of a highresolution time frame. Based on the quartz and mica percentage fluctuations, one large- and seven small-scale sequences are defined. The large-scale sequence boundaries correlate with third-order sequence boundaries Ox 8 and Kim 1 defined by Hardenbol et al. (1998). The large-scale maximum-flooding surface corresponds to the base of the most calcareous interval and to the maximum abundance of marine phytoplankton and opaque, equidimensional phytoclasts. The small-scale sequences correspond to the 100-kyr orbital eccentricity cycle. Calcareous nannofossils and clay minerals were used as palaeoclimatic proxies. Nannofossil abundances and fluxes are lower in the upper part than in the lower part of the interval studied, suggesting a decrease in seasurface trophic conditions, also shown by an increase in the relative abundance of oligotrophic taxa. This upper part is also characterised by an increase in smectite, which coincides with the base of the large-scale highstand deposit, and is interpreted as reflecting the establishment of dry conditions. A first increase in smectite occurs in the lower part of the succession, and coincides with high percentages of quartz and mica. This latter mineralogical assemblage is interpreted as recording the onset of the Late Jurassic to Early Cretaceous rifting stage, which occurred just before the Planula-Galar ammonite subzone transition. The present study points out a return toward optimum conditions for carbonate sedimentation only 300 kyr after the prominent increase in siliciclastic input due to tectonic activity. The recovery of carbonate production was accompanied by a global sea-level rise and by decreasing rainfall on nearby land.
Published: 2014
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24. High frequency floral changes at the Paleocene–Eocene boundary revealed by comparative biomarker and palynological studies

Author: Claude Le Milbeau, Christian Dupuis, Jérémy Jacob, Sylvain Garel, Florence Quesnel, Mohammed Boussafir, Johann Schnyder, François Baudin, Emile Roche, Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Département de Géologie, Université de Liège, Géologie GFA, Faculté polytechnique de Mons, Université de Mons (UMons)-Université de Mons (UMons), ANR-10-JCJC-0607,PalHydroMil,Reconstructions paléohydrologiques à partir du dD de lipides produits par les végétaux supérieurs. Calibration, validation et application aux variations hydrologiques dans les Alpes pendant l'âge du Bronze(2010), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Vascular plant, PETM, 010504 meteorology & atmospheric sciences, Molecular geochemistry, Dieppe-Hampshire Basin, 010502 geochemistry & geophysics, medicine.disease_cause, 01 natural sciences, Sedimentary depositional environment, Paleontology, Geochemistry and Petrology, Pollen, Botany, Pollen and spores study, medicine, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, 0105 earth and related environmental sciences, Floral changes, Palynology, biology, Paleohydrology, fungi, food and beverages, Juglandaceae, Vegetation, 15. Life on land, biology.organism_classification, Spore, 13. Climate action, Geology, Marine transgression
Abstract: International audience; The Cap d'Ailly area (Upper Normandy, France) shows several terrestrial–lagoonal sections recording the negative carbon isotope excursion (CIE) associated with the Paleocene–Eocene Thermal Maximum (PETM; 55.8 Ma). A study of the biomarkers and spore/pollen content of the Vasterival section gave com-plementary information on paleofloral changes that occurred around the Paleocene–Eocene (P–E) bound-ary. Aliphatic hydrocarbon fractions revealed a high abundance of vascular plant biomarkers, including tricyclic diterpanes derived from conifers, fernenes derived from ferns and des-A-triterpenes derived from angiosperms. Whereas the vegetation of the depositional environment surroundings seemed alter-nately dominated by ferns and angiosperms (revealed from biomarkers), the regional flora seemed dom-inated strictly by angiosperms such as Juglandaceae (revealed by pollen). Spore/pollen assemblages revealed no major turnover in the paleovegetation, but slight variation in vegetation composition. How-ever, both biomarkers and spores/pollen exhibited two intervals of rapid floral change: the first occurred around the P–E boundary and the second at the top of the strictly terrestrial unit that coincides with a marine transgression. Comparison of the data with published paleoclimatic results, obtained from the same samples, indicated that the first interval of floral change correlates with strong paleohydrological perturbations, whereas the second is linked to an increasing marine influence.
Published: 2014
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25. Refined bio- (benthic foraminifera, dinoflagellate cysts) and chemostratigraphy (δ 13 C org ) of the earliest Eocene at Albas-Le Clot (Corbières, France): implications for mammalian biochronology in Southern Europe

Author: Johann Schnyder, Edwige Masure, Jean-Yves Storme, Laurent Marivaux, Bernard Marandat, Sylvain Adnet, Monique Vianey-Liaud, Rodolphe Tabuce, Johan Yans, Josep Serra-Kiel, Fondation Universitaire Notre Dame de la Paix ( FUNDP ), Facultés Universitaires Notre-Dame de la Paix, Institut des Sciences de l'Evolution de Montpellier ( ISEM ), Université de Montpellier ( UM ) -Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique ( CNRS ), Centre de recherche sur la Paléobiodiversité et les Paléoenvironnements ( CR2P ), Muséum National d'Histoire Naturelle ( MNHN ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ), University of Barcelona, Institut des Sciences de la Terre de Paris ( iSTeP ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ), Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226, Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Belgian Science Policy Office [BR/121/A3/PALEURAFRICA], Spanish Ministry of Science and Innovation [CGL2011-27869], project EVOLTHERM of the Institut des Sciences de l'Evolution of Montpellier, Fondation Universitaire Notre Dame de la Paix (FUNDP), Facultés Universitaires Notre Dame de la Paix (FUNDP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur la Paléobiodiversité et les Paléoenvironnements (CR2P), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UR226
Subjects: PETM, Le Clot, Stratigraphy, Fauna, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, [ SDU.STU.ST ] Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, Corbières, Foraminifera, Paleontology, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Chemostratigraphy, Biochronology, 14. Life underwater, [ SDU.STU.PG ] Sciences of the Universe [physics]/Earth Sciences/Paleontology, Mammals, Eocene Thermal Maximum 2, biology, "Sparnacian", Corbieres, Geology, ``Sparnacian'', biology.organism_classification, [ SDU.STU.GC ] Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Isotopes of carbon, Benthic zone, carbon isotopes, [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology, Paleogene
Abstract: International audience; Utilizing bio- and chemostratigraphy, we propose an integrated dating of the upper part of the continental ``Sparnacien des Corbieres'' and the overlying marine ``lower-middle Ilerdian'' succession of Albas-Le Clot (Corbieres, France), in order to refine the position and age of the Le Clot mammalian locality. Our data show that this locality, which has yielded a mammal fauna early Ypresian in age (close to MP7, Mammal Paleogene level), is located above the end of the carbon isotope excursion (CIE) the base of which defines the Paleocene-Eocene boundary. The Le Clot mammalian locality is therefore younger than the Paleocene-Eocene Thermal Maximum (PETM), and also younger than the Dormaal MP7 reference fauna in Belgium, which is correlated with the onset of the CIE (nannoplankton Zone NP9b). Moreover, we demonstrate that the Le Clot mammalian locality is older than the Eocene Thermal Maximum 2 (ETM2) event, located in the lower part of NP11 Zone. Associated with the ages of benthic foraminifera and dinocysts observed in the succession, our delta C-13(org) chemostratigraphy suggests that the Le Clot locality is correlated to the upper NP10-lower NP11 Zones. The refined location of the CIE in the Albas-Le Clot section is discussed because two carbon isotope excursions are potentially recorded in the upper ``Sparnacien des Corbieres'', here recognized as mainly Thanetian in age.
Published: 2014
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26. Palaeontology of the Purbeck-type (Tithonian, Late Jurassic) bonebeds of Chassiron (Oléron Island, western France)

Author: Haiyan Tong, Johann Schnyder, Véronique Daviero-Gomez, Géraldine Garcia, Michel Ballèvre, Jean-Michel Mazin, Joane Pouech, Romain Vullo, Eric Buffetaut, Renaud Bourgeais, Jean-Paul Billon-Bruyat, Bernard Gomez, Jean-Claude Rage, Didier Néraudeau, Séverin Morel, Dominique Abit, Géosciences Rennes (GR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS), Terre, Temps, Traçage, Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Section d'Archéologie et Paléontologie, Office de la Culture, Section d'Archéologie et Paléontologie, Office de la Culture, République et Canton du Jura, Hôtel des Halles, 2900 Porrentruy, Laboratoire de géologie de l'ENS (LGENS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut International de Paléoprimatologie, Paléontologie Humaine : Evolution et Paléoenvironnement (IPHEP), Centre National de la Recherche Scientifique (CNRS)-Université de Poitiers, Paléoenvironnements, Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), PaleoEnvironnements et PaleobioSphere (PEPS), Université Claude Bernard Lyon 1 (UCBL), Centre de recherche sur la Paléobiodiversité et les Paléoenvironnements (CR2P), Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Palaeontological Research and Education Centre, Mahasarakham University, Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), 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), Université de Poitiers-Centre National de la Recherche Scientifique (CNRS), 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)-École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010506 paleontology, biology, Ecology, Fauna, General Engineering, Vertebrate, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Euryhaline, Jurassic, 010502 geochemistry & geophysics, 01 natural sciences, Sedimentary depositional environment, Paleontology, Type (biology), biology.animal, Facies, Vertebrates, Assemblage (archaeology), Tithonian, 14. Life underwater, France, Bonebeds, Geology, 0105 earth and related environmental sciences, Invertebrate
Abstract: International audience; The paralic flora and fauna from the Late Jurassic of Chassiron (Oléron Island, western France) are described. The Tithonian-aged bonebeds of Purbeck facies of this locality have yielded a rich and diverse vertebrate assemblage including fishes, amphibians, reptiles and mammals, alongside numerous plant and invertebrate remains. The Chassiron locality thus appears as a peculiar Konzentrat-Lagerstätte in which most of the palaeoecosystem's biological components (both aquatic and terrestrial) have been preserved. The depositional environment was probably subject to salinity fluctuations, as indicated by the co-occurrence of freshwater and euryhaline organisms. This is one of the richest localities and the first mammal-bearing site known from the Jurassic of France.
Published: 2014
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27. An unexpected record of the PETM in terrestrial and organic sediments of Avesnois, between the Paris and Belgian Basins, NW Europe

Author: Jean-Yves Storme, Emile Roche, Christian Dupuis, Jean-Marc Baele, Florence Quesnel, Chantal Bourdillon Thierry Smith, Johan Yans, Pieter Missiaen, Christine Fléhoc, Johann Schnyder, Paola Iacumin, and Alina I. Iakovleva
Subjects: Sedimentary depositional environment, Palynology, Paleontology, Marl, engineering, Geology, Biostratigraphy, engineering.material, Paleosol, Glauconite, Conglomerate, Marine transgression
Abstract: The stratigraphy of the Late Paleocene-Early Eocene has been revised in Avesnois thanks to drillings supporting a geological mapping project. Detailed sampling and analyses were performed along selected drillings, among which sedimentological, mineralogical, chemostratigraphic (δ13Corg), biostratigraphic and palynological data have been obtained. New Mbs/Fms are defined around the Paleocene-Eocene boundary (PEb) and compared to the lithostratigraphic nomenclatures of the Belgian and Paris Basins (Steurbaut, 1998; Aubry et al., 2005). Biostratigraphy based on the study of foraminifera and mammal fauna, palynological content and chemostratigraphy enable correlation to be established between adjacent basins as well as sea level and landscape evolutions to be refined during this critical interval. Upper Thanetian marine units In the AVE 007-drilling (Mormal Forest, Locquignol, between Englefontaine, Landrecies and Maroilles villages), the Coniacian chalk is overlain by a flint conglomerate, whose sandy-clayey matrix contains Thanetian pollen and dinocysts. Widespread in Avesnois and containing often reworked Upper Cretaceous foraminifera and occasionally glauconite, this unit constitutes the Vervins Mb (cf. 'Argile a silex de Vervins' interpreted as a marine conglomerate by Gosselet, 1879). It is often overlain by the Mondrepuis-Bettrechies Sand Mb (cf. 'Sable verts de l'Avesnois'), a thin sandy glauconiferous unit, more clayey and silty westward (cf. 'Tuffeau de Valenciennes' Mb). The three Mbs constitute the Hainaut-Valenciennois Fm and can be correlated to the Belgian Grandglise Mb (upper part of the Hannut Fm) and Bois-Gilles Fm, and to the Paris Basin Châlons-sur-Vesles and Bracheux Fms, all Thanetian in age. Uppermost Paleocene to lowermost Eocene terrestrial units In AVE 007 the Vervins Mb is unconformably overlain by flint gravels (Mormal Mb), then a pyritic sand (Le Quesnoy Sand Mb, cf. 'Sables et Gres du Quesnoy' of Gosselet, 1890), and a lignitic clay (Locquignol Mb), silty and ochreous at the top. All but the top ochreous paleosol contain spores and pollen grains and are devoid of dinocysts, they were thus probably deposited in terrestrial environments. The Carbon Isotope Excursion (CIE) of the PEb begins below the top of the sandy unit and continues in the lignitic clay. The palynological study confirms the Locquignol Mb's earliest Eocene age and allows correlation with the base of the Tienen Fm. To the East of AVE 007 along the Belgium-France border, fluvial fossiliferous gravels and sands have been studied in past sand quarries (Erquelinnes Sand Mb). Above a sharp unconformity, they i) overly Upper Thanetian marine sands (Bois-Gilles Fm, NP9a, then Grandglise Mb, NP8), ii) contain a mammal fauna referred as MP7 in the Mammalian biochronological scale for the European Paleogene (Missiaen et al., 2013) and iii) record the first part of the CIE onset in the basal fossiliferous gravel and marl beds. Three km west of Erquelinnes and toward AVE 007 a few drillings have recognized a sandy and pyritic unit containing resinite fragments, lignite and peat beds (Vieux Reng Mb), overlying a thin basal flint gravel bed (Mormal Mb). These five Mormal, Le Quesnoy, Locquignol, Vieux-Reng and Erquelinnes Sand Mbs form the Sambre Fm. Such fluvial gravels and sands, more or less lignitic, clayey or marly are widespread in northern France and southeastern Belgium. They belong to the so-called Upper "Landenian" and are correlated to the Tienen Fm. In AVE 007, they record the CIE onset marking the PEb and 2.5 m of Upper Paleocene fluvial units, in contrast with Belgian drillings such as Doel and Kallo where a hiatus is present at the PEb. Lower Ypresian hiatus and marine units In AVE 007, a laminated silty unit overlies the Locquignol Mb, contains dinocysts Wetzeliella sp. and agglutinated foraminifera similar to those of the base of the Orchies Clay Mb. Widespread in Avesnois-Valenciennois that marine unit is named Avesnois Mb, it is locally richer in very fine sand, and correlated to the base of the Kortrijk Clay Fm (Ieper Gp). In Avesnois, Sparnacian lagoonal units are absent upon the terrestrial ones described above, again marking a reverse trend when compared with the Belgian and adjacent Basins. This may result from restricted terrestrial environments coinciding with Variscan accidents and structural highs between the Artois anticline and Ardenne Masssif, or to their deposition followed by subsequent erosion prior to the Lower Ypresian marine transgression (cf. sea level drop 2 of Dupuis et al, 2011). Correlations and PETM impact on land All terrestrial units here described fill fluvial channels incised in marine Thanetian and older units such as the Cretaceous or the Variscan basement in Avesnois and Belgium, as already reported elsewhere in northern France (cf. sea level drop 1 of Dupuis et al., 2011). They exhibit locally cross stratification, lignite, flora or vertebrate fauna, for example at Leval, Hoegaarden and Dormaal, and/or are intensively silicified with scarce root or leaf casts. Similar fluvial sediments and silcretes are recognized in the first Sparnacian units and paleogeography of the Paris, Dieppe-Hampshire and London Basins, where the PEb is also present, the CIE being recorded on thicknesses between 3 m (as in AVE 007) to >20 m (as in Sinceny). These features may be regarded now as constant in those Sparnacian landscapes recording the PETM, with very rapid lateral and vertical facies shift, particular paleosols, a few fossiliferous fluvial to lacustrine units and variable deposition rates/sediments preservation. Terrestrial sediments, flora and fauna have been described there before the CIE onset as well, for example at Cobham, Vasterival or Rivecourt (e.g. Smith et al., 2014). Lihons, an intermediate outlier situated between AVE 007 and Sparnacian sites of those basins has further been investigated: marine Thanetian sands are overlain by thin fluvial, lacustrine then lagoonal sediments, the two latter recording the CIE of the PETM on an interval 4 m thick. Here again the basal terrestrial sediments have been deposited before the PEb. In AVE 007, depositional environments are fluvial for the Mormal and Le Quesnoy Mbs, and evolve toward flood plain then palustrine ones for the Locquignol Mb, probably here after the river bed migration, but still recording sporo-pollen fluvial inputs from the hinterland, the whole indicating a rather humid subtropical climate. Compared to the Locquignol Mb, the sporopollinic assemblage of the Mormal and Le Quesnoy Mbs (below the CIE onset) is different, particularly regarding the Normapolles distribution, the Tricolpates, Tricolporates and Monocolpates relative pollen abundances and the pollen ratio of Plicapollis pseudoexcelsus/Juglandaceae. In the three Mbs, rapid vertical variations characterize pollen and fern spores assemblages, with peaks of particular taxa reaching 25% of the total counts, such as for P. pseudoexcelsus, T. platycaryoides, C. dorogensis, P. mcgregorii, T. robustus. They suggest rapid floral changes in the catchment and/or sources changes in the surrounding landscapes compartments for the rivers supplying the fluvial sediments. Resinite particles are irregularly abundant as well as microcharcoals are occasionally abundant, notably slightly before the CIE onset and 1.5 m above it, still within the CIE. The clay mineral assemblage is homogeneous along marine Thanetian units and strongly dominated by Illite-Smectite (IS) mixed layers, whatever the facies, while it is more variable in the marine Ypresian silts (abundant IS, followed by Kaolinite, Illite, Chlorite and Vermiculite). In contrast terrestrial units are dominated by IS followed by Kaolinite, Illite and very rare Chlorite, and no variation is observed across the PEb. Those data would suggest that major environmental changes have regionally begun before the PETM, at the very end of the Paleocene, when terrestrial realm has settled, in relation with a regional uplift. Clay minerals reflect constant reworking of preexisting weathering profiles established upon Cretaceous strata and Variscan basement, while vegetation modifications are subtle and more likely attributable to changes of depositional environments
Published: 2014

28. Paleohydrological and paleoenvironmental changes recorded in terrestrial sediments of the Paleocene-Eocene boundary (Normandy, France)

Author: Christian Dupuis, François Baudin, Mohammed Boussafir, Jean-Yves Storme, Claude Le Milbeau, Jérémy Jacob, Christine Fléhoc, Florence Quesnel, Johan Yans, Johann Schnyder, Sylvain Garel, Alina I. Iakovleva, Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), GFA - Polytech Mons, Université de Mons-Hainaut, FUNDP, UCL, Laboratory of Paleofloristics, Geological Institute, Russian Academy of Sciences [Moscow] (RAS), Fondation Universitaire Notre Dame de la Paix (FUNDP), Facultés Universitaires Notre Dame de la Paix (FUNDP), BRGM ('Paléosurface éocène-PETM' research project), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)
Subjects: PETM, Continental ecosystems, 010504 meteorology & atmospheric sciences, [SDE.MCG]Environmental Sciences/Global Changes, Dieppe-Hampshire Basin, Holocene climatic optimum, 010502 geochemistry & geophysics, Oceanography, Paleoenvironments, 01 natural sciences, Swamp, Carbon cycle, Paleontology, Organic matter, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, Earth-Surface Processes, Hydrogen isotopes, chemistry.chemical_classification, geography, geography.geographical_feature_category, Paleohydrology, Carbon isotopes, 15. Life on land, Palynofacies, chemistry, 13. Climate action, Isotopes of carbon, Eutrophication, Geology, Marine transgression
Abstract: International audience; The Paleocene-Eocene boundary (55.8 Ma) is associated with the Paleocene-Eocene Thermal Maximum (PETM), which is characterized by a negative Carbon Isotope Excursion (CIE), reflecting a major perturbation of the carbon cycle, and by an extreme and rapid global warming. The Cap d'Ailly area (Upper Normandy, France), in which previous studies have revealed the Paleocene-Eocene transition, is a reference locality for organic-rich terrestrial and lagoonal deposits of the "Sparnacian" stage, widespread in Northwestern Europe. In this study, we focus on the organic matter content of the Vasterival section. Organic data (Rock-Eval, palynofacies, biomarker analyses and compound specific isotope analyses) were acquired in order to constrain the paleoenvironmental and paleohydrological changes that occurred at the Paleocene-Eocene boundary. Stable carbon isotope compositions of higher plant leaf wax n-alkanes reveal a CIE of − 4.5 ‰, extending throughout the second half of the studied section. Palynofacies observations reveal: (i) an abrupt shift from a closed, quiescent marsh pond to an open eutrophic swamp subjected to algal blooms, concomitant with the onset of the CIE; and (ii) the evolution from a swamp to a tidal flat due to the marine transgression that occurred during the PETM. Higher plant biomarkers and their hydrogen isotopic composition compared to nitrogen analyses suggest: (i) dry episodes just before the PETM that may help to understand the triggering of this hyperthermal event; (ii) a moister climate associated with a stronger seasonality during the early PETM.
Published: 2013
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29. Berriasian and early Valanginian environmental change along a transect from the Jura Platform to the Vocontian Basin

Author: Thierry Adatte, Hubert Arnaud, Johann Schnyder, Chloé Morales, Jorge E. Spangenberg, Annie Arnaud-Vanneau, Karl B. Föllmi, Silvia Gardin, Institute of Earth Sciences, Université de Lausanne (UNIL), Centre de recherche sur la Paléobiodiversité et les Paléoenvironnements (CR2P), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), and Université de Lausanne = University of Lausanne (UNIL)
Subjects: Palynology, 010506 paleontology, Environmental change, biology, Carbonate platform, Stratigraphy, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Geology, 010502 geochemistry & geophysics, biology.organism_classification, 01 natural sciences, Foraminifera, chemistry.chemical_compound, Paleontology, chemistry, 13. Climate action, Carbonate, Sequence stratigraphy, Sedimentary rock, 14. Life underwater, 0105 earth and related environmental sciences, Marine transgression
Abstract: International audience; Valanginian sedimentary archives display a positive anomaly in the carbon-isotope record which is associated with a crisis in neritic and pelagic carbonate production. This study aims to reconstruct the evolution of palaeoenvironments in the Jura area and the Vocontian Basin during late Berriasian and early Valanginian times, in order to better understand the controlling factors leading to the Valanginian episode of major environmental change. Three sections along a transect through the Jura platform (Switzerland and France) and the Vocontian Basin (France) have been studied. Stratigraphic correlations have been established by combining biostratigra- phy (benthic foraminifera, ammonites and calpionellids), with geochemistry (δ13C trends) and sequence stratigraphy. A change from a rimmed ramp to a swell-dominated ramp morphology is observed through the Berriasian-Valanginian boundary. The disappearance of the barrier appears to have been controlled by large sea-level variations in combination with the arrival of significantly more humid climate conditions. This barrier played a major role in the distribution of geochemical, mineralogical and palynological fluxes towards the basin: during the Berriasian, continental fluxes (detrital particles, nutrients, pollen and spores) were buffered by the platform morphology, whereas in the early Valanginian they were more readily transported towards the basin. The initiation of a major transgression onto lateritic soils, leading to their intense reworking, instigated a fertilization of ocean waters during the earliest Valanginian and with that a change towards heterozoan carbonate production, and subsequently to the demise of the already weakened carbonate platform
Published: 2013
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30. Late Jurassic-Early Cretaceous faulting in the Southeastern French basin: does it reflect a tectonic reorganization?

Author: Johann Schnyder, Mohamed Benzaggagh, Catherine Homberg, Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), and Université Moulay Ismail (UMI)
Subjects: geography, geography.geographical_feature_category, Rift, 010504 meteorology & atmospheric sciences, Aptian, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Geology, Structural basin, Fault (geology), 010502 geochemistry & geophysics, 01 natural sciences, Cretaceous, Tectonics, Paleontology, Sedimentary rock, 14. Life underwater, Lithification, 0105 earth and related environmental sciences
Abstract: We present new data constraining the Late Jurassic to Early Cretaceous evolution of the Southeastern French basin (SFB). Meso-scale faults with displacement of several decimeters to 1–2 meters were sampled for geometric and kinematic data analysis and the faulted and un-faulted sedimentary units were examined for sedimentologic and bio-stratigraphic purposes. Small-scale faults were also extensively collected to determine the local stress states during this period. Meso-scale normal faults formed during sediment deposition or before its complete lithification attest of a recurrent activity in the Late Jurassic to Early Cretaceous period in an overall extensional context. The fault network cutting the Oxfordian to Aptian sequences included normal faults of various trends, ranging between WSW-ENE and NNW-SSE. We show that the deformation mechanism in the SFB drastically changed in the Jurassic-Cretaceous transition (latermost Tithonian?), with the direction of extension rotating from a WNW-ESE to a NNE-SSW direction. Lateral thickness variation of the sequences, redistribution of sediments, faulting at various scales concur that the Early Cretaceous period marks a tectono-stratigraphic reorganization of the basin. We suggest that it traduces the rifting and later opening of the North Atlantic (main branch and bay of Biscay branch).
Published: 2013
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31. Purbeck beds (Late Jurassic) in the Phare de Chassiron section (Île d'Oléron, NW Aquitaine Basin, France): refined age-assignment and long-term depositional sequences

Author: François Baudin, Bruno Galbrun, Marc de Rafélis, Jean-François Deconinck, Claude Colombié, Sylvia Gardin, Johann Schnyder, Roger Jan Du Chêne, Institut des Sciences de la Terre de Paris ( iSTeP ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ), Biogéosciences [Dijon] ( BGS ), Université de Bourgogne ( UB ) -AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] ( LGL-TPE ), École normale supérieure - Lyon ( ENS Lyon ) -Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Centre de recherche sur la Paléobiodiversité et les Paléoenvironnements ( CR2P ), Muséum National d'Histoire Naturelle ( MNHN ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Biogéosciences [UMR 6282] (BGS), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), 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), Centre de recherche sur la Paléobiodiversité et les Paléoenvironnements (CR2P), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Biogéosciences [UMR 6282] [Dijon] (BGS), Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique (CNRS), 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: 010506 paleontology, Dinoflagellate, Magnetostratigraphy, Late Jurassic, Paleontology, Purbeck beds, Structural basin, 010502 geochemistry & geophysics, [ SDU.STU.ST ] Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, 01 natural sciences, Aquitaine Basin, Cretaceous, Palynofacies, Sedimentary depositional environment, Space and Planetary Science, Section (archaeology), [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, Facies, Nannofossils, 14. Life underwater, Sedimentology, Geology, 0105 earth and related environmental sciences
Abstract: 15 pages; International audience; In western european basins, lowering of relative sea-level during the Late Jurassic-Early Cretaceous led to the widespread deposition in numerous basins of so-called Purbeck facies. Age-assignment and longdistance correlations are difficult to establish in such shallow marine to continental deposits, where ammonites are generally lacking. This paper aims to present new biostratigraphical and sedimentological data from the Phare de Chassiron section, located at the western part of the Aquitaine Basin (SW France), where Purbeck beds crop out. Marine bands, interfingered within the Purbeck beds, allow refining the age-assignment of these beds using dinoflagellate cysts, calcareous nannofossils and magnetostratigraphy. Most of the Purbeck beds appear to have a Tithonian age. Uppermost beds of the section, although not precisely dated, are not younger than the Early Berriasian. Field sedimentology, palynofacies and trace-element data (strontium) on carbonates, allow depositional environments to be characterized and a sequence-stratigraphy scheme to be established. This section provides an unique, continuous record, within the Aquitaine Basin, of the final exposure, during the Tithonian, of the former Late Kimmeridgian open-marine platform. The Phare de Chassiron may be considered as one of the most important exposures of Purbeck facies of Tithonian age in Europe.
Published: 2012
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32. Ecological succession evidence in an Upper Jurassic coral reef system (Izwarn section, High Atlas, Morocco)

Author: Fabienne Giraud, Karim Ezaidi, Johann Schnyder, Bertrand Martin-Garin, Belkacem Kabbachi, Claude Colombié, Nicolas Olivier, Jean-Jacques Cornée, 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), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Bassins, Géosciences Montpellier, Université des Antilles et de la Guyane (UAG)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles et de la Guyane (UAG)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre (ISTerre), Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-PRES Université de Grenoble-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Département de Géologie [Agadir], Université Ibn Zohr [Agadir], 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), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), and Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])
Subjects: 010506 paleontology, Coral, Fringing reef, Reef, [SDE.MCG]Environmental Sciences/Global Changes, Window (geology), Ecological succession, 010502 geochemistry & geophysics, 01 natural sciences, Paleontology, Assemblage (archaeology), Upper Jurassic, 14. Life underwater, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Scleractinian corals, 0105 earth and related environmental sciences, geography, geography.geographical_feature_category, Microbialites, Coral reef, Morocco, Oceanography, Space and Planetary Science, Section (archaeology), Geology
Abstract: International audience; Late Jurassic coral reefs are present in the Western High Atlas of Morocco along the eastern paleomargin of the young Atlantic Ocean. The Izwarn section shows two reef units made of scleractinian corals and microbialites, included in a progradational shallowing-upward succession. Changes in reefal composition and structure observed in a ca. 50 cm-thick interval at the base of the reef unit 1 are interpreted to represent the first well-documented ecological succession in Late Jurassic reefs. Bioclastic deposits, sparse and poorly diversified corals (five genera) preserved in life position, and finally a more diversified coral assemblage (11 genera) building a reef framework with stromatolitic crusts reflect pioneer, colonization and diversification stages, respectively. A specific depth window, where light was reduced but sufficient for a catch-up growth mode and below the erosive action of waves, probably at the lower slope of a fore-reef area, has made possible the development and the record of this ecological succession. With a more diversified coral assemblage (16 genera), the reef unit 2 reflects shallower and well-agitated waters of a fore-reef area. Overlaying this second reef unit, the upper part of the section reveals back-reef deposits made of reworked reef elements, whereas a putative reef crest area is not recorded.
Published: 2012
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33. Shallow-water marl-limestone alternations in the Late Jurassic of western France: Cycles, storm event deposits or both?

Author: Johann Schnyder, Claude Colombié, Damien Carcel, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), PaleoEnvironnements et PaleobioSphere (PEPS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), 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), and Université Claude Bernard Lyon 1 (UCBL)
Subjects: 010506 paleontology, Milankovitch cycles, Stratigraphy, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Geology, 010502 geochemistry & geophysics, 01 natural sciences, Sedimentary depositional environment, Waves and shallow water, Paleontology, chemistry.chemical_compound, chemistry, 13. Climate action, Marl, Facies, Carbonate, 14. Life underwater, Bioturbation, Sea level, 0105 earth and related environmental sciences
Abstract: International audience; The contribution of event deposits to various basin fills can be very significant, higher than 90% in some cases. Events may lead to the formation of marl–limestone alternations, which can also result from cyclic changes in sea level or climate, for example. The marl–limestone alternations of the Late Jurassic of western France contain abundant coarse-grained accumulations that resemble storm deposits described in other western European successions. The detailed analysis of facies evolution and hierarchical, high-frequency stacking pattern of depositional sequences of the Phare de Chassiron section (Ile d'Oléron, western France) allows the controls on marl–limestone formation to be defined. This section contains nearshore and shallow-marine mud deposits that were exposed to high-energy events. Elementary, small-, and medium-scale depositional sequences are defined. The stacking-pattern and the duration of these sequences suggest an orbital control on sedimentation. Precession (20 ka) cycles notably controlled the formation of elementary sequences that correspond to marl–limestone alternations. The deposition of marly or carbonate mud occurred in this storm-dominated system because of muddy sea beds, the gentle slope of the shelf, and the great amount of particles in suspension, which reduced water energy resulting from storms. Sediment supply was also sufficient to limit bioturbation and favour the preservation of numerous storm deposits. The production of carbonate mud was localised on positive structures and partly controlled by Milankovitch-scale sea-level cycles. Transport by storms of carbonate mud to the adjacent marly depressions during high carbonate production periods led to the formation of calcareous beds. Marl–limestone alternations in the Late Jurassic of western France therefore result from the combined effects of cyclic changes in carbonate production and high-energy, episodic events.
Published: 2012
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34. Calpionelles et microfaunes pélagiques du Jurassique supérieur - Crétacé inférieur dans les formations Shal et Kolur (Montagnes du Talesh, chaîne de l'Elbourz, Nord-Ouest Iran). Répartition stratigraphique, espèces nouvelles, révision systématique et comparaisons régionales

Author: Johann Schnyder, Fabrizio Cecca, Mahmoud Reza Majidifard, Kazem Seyed-Emami, Mohamed Benzaggagh, Université Moulay Ismail (UMI), Centre de recherche sur la Paléobiodiversité et les Paléoenvironnements (CR2P), Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), School of Mining Engineering, University College of Engineering, University of Tehran, Geological Survey of Iran, and Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010506 paleontology, Elbourz, Calpionellids, Biostratigraphy, Paleontology, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Alborz, Iran, 15. Life on land, 010502 geochemistry & geophysics, Jurassique supérieur, 01 natural sciences, Biostratigraphie, Lower Cretaceous, Upper Jurassic, Calpionelles, ComputingMilieux_MISCELLANEOUS, Crétacé inférieur, 0105 earth and related environmental sciences
Abstract: International audience; Two sections corresponding respectively to the Shal (Callovian – Lower Berriasian) and Kolur Formations (Berriasian – Valanginian in the sampled interval) have been studied in the Talesh Mountains (North-West Iran), an area whose sedimentary successions formed on the northern margin of the Eastern Tethys during the Mesozoic. This study allowed the identification of the different calpionellid zones and sub-zones defined in basin successions of the Western Tethys. In the upper part of Shal Formation the Chitinoidella boneti (base of the Upper Tithonian) and B1 sub-zones (base of the Calpionella alpina zone, lowermost Berriasian) have been recognized. The rich and diverse calpionellid faunas allowed us to recognize in the Kolur Formation B3 (top of the C. alpina zone), C1, C2 (Calpionella elliptica zone), D1, D2, D3 (Calpionellopsis zone) subzones and E (Calpionellites zone) and F (Tintinnopsella zone). The E zone has been subdivided in two sub-zones: E1 and E2, which is characterized by the disappearance of the genus Calpionellopsis. Thirty calpionellid species have been described. Fifteen of them are new: Calpionellites medius nov. sp., Calpionellites minor nov. sp., Remaniella longocadischiana nov. sp., Remaniella minicadischiana nov. sp., Tintinnopsella curva nov. sp., Tintinnopsella duranddelgai nov. sp., Tintinnopsella elmii nov. sp., Tintinnopsella largovalata nov. sp., Tintinnopsella lehegarati nov. sp., Tintinnopsella longovalata nov. sp., Tintinnopsella maxilonga nov. sp., Tintinnopsella minicarpathica nov. sp., Tintinnopsella pseudoblonga nov. sp., Tintinnopsella pseudocarpathica nov. sp. and Tintinnopsella pseudosimplex nov. sp. Amongst the other pelagic microfossil groups, Globochaete and calcispheres (“microproblematics”), often abundant in Western Tethyan Upper Jurassic – Lower Cretaceous pelagic successions, are absent in the Shal Formation and extremely rare in the Kolur Formation despite its lithofacies usually suited for preservation of such microfossils. It is worth noting that in Kolur section the peak of Cadosina fusca in the D1 sub-zone and the occurrence of Stomiosphaera wanneri in the C zone have been observed similarly to successions of Moroccan external Rif. As in most basins of the Western Tethys, Saccocoma remains are frequent in the upper part of the Shal Formation and disappear after the appearance of Chitinoidella in the uppermost Tithonian. Radiolarians with spherical tests are represented by two morphologies:one of common size, called morphology A, occurs at different levels of both Shal and Kolur Formations, while the larger one, called morphology B, occurs in the Upper Tithonian of the Shal Formation and becomes frequent in the Berriasian – Lower Valanginian beds of the Kolur Formation. The first morphology is relatively frequent in coeval successions of Western Tethyan basins, while the second is rarely reported in the literature. Holothurian sclerites are often abundant in the Lower Berriasian – Lower Valanginian interval, whereas they are rare (or scarcely reported in the literature) in coeval successions of the southern margin of the Western Tethys. Chitinoidella, calpionellids, Saccocoma, protoglobigerinid forams, radiolarian of the morphology A are fossil groups that commonly occur in Tethyan basins. On the contrary, Globochaete and calcispheres were seemingly adapted to local ecological conditions, which were probably different from those of the study area. However, preservation bias for these particular microfossils cannot be excluded in the Kolur section, which is locally affected by faulting.; L’étude de deux coupes correspondant respectivement aux Formations Shal (Callovien – Berriasien inférieur) et Kolur (Berriasien – Valanginien) dans la région du Talesh (Nord-Ouest de l’Iran, marge nord de la Téthys orientale) a permis de caractériser les différentes zones et sous-zones des calpionelles, définies dans des séries des bassins de la Téthys occidentale. Ainsi, les sous-zones à Chitinoidella boneti (base du Tithonien supérieur) et B1 (base de la zone à Calpionella alpina, base du Berriasien inférieur) ont été caractérisées dans la partie supérieure de la Formation Shal. Les sous-zones B3 (sommet de la zone à C. alpina), C1, C2 (zone à Calpionella elliptica), D1, D2, D3 (zone à Calpionellopsis), les zones E (ou à Calpionellites) et F (ou à Tintinnopsella) ont été caractérisées dans la Formation Kolur sur la base d’une riche faune de calpionelles. La zone E a été subdivisée en deux sous-zones : E1 et E2. La première sous-zone est marquée par la persistance du genre Calpionellopsis. Trente espèces de calpionelles ont été décrites. Quinze espèces sont nouvelles, dont 11 du genre Tintinnopsella, deux du genre Remaniella et deux du genre Calpionellites. Parmi les autres microfaunes pélagiques de la limite Jurassique – Crétacé, les Globochaete et les calcisphères (ou microproblématiques), qui sont souvent abondants dans les séries d’âge Jurassique terminal – Crétacé basal des bassins de la Téthys occidentale, sont par contre absents dans la Formation Shal et très rares dans la Formation Kolur. Cette dernière présente pourtant des faciès pélagiques, favorables à la conservation des spécimens de ces deux groupes fossiles. On peut néanmoins signaler, comme dans les séries du Rif externe au Maroc, un pic à Cadosina fusca dans la sous-zone D1 et la présence de Stomiosphaera wanneri dans les niveaux de la zone C. Les Saccocoma, souvent fréquents dans la moitié supérieure de la Formation Shal, disparaissent, comme dans la plupart des séries des bassins de la Téthys occidentale, dans des niveaux assez hauts du Tithonien supérieur, bien après l’apparition de Chitinoidella. Les radiolaires, à coque sphérique, sont représentés par deux morphologies : une de taille normale qualifiée de morphologie A, présente dans les différents niveaux des deux formations étudiées ; une autre de taille plus grande, qualifiée de morphologie B, présente dans les niveaux supérieurs de la Formation Shal (Tithonien supérieur) et devenant fréquente dans les niveaux du Berriasien à Valanginien inférieur de la Formation Kolur. La première morphologie est assez abondante dans les séries de même âge des bassins de la Téthys occidentale ; la seconde y est par contre rarement signalée par les auteurs. Notons que les niveaux du Berriasien inférieur à Valanginien inférieur de la coupe de Kolur contiennent, souvent et en abondance, des sclérites d’holothuries. Les restes de ces organismes sont rares, ou peu signalés dans la littérature, dans les séries de même âge des bassins de la marge sud de la Téthys occidentale. Certains groupes fossiles de part et d’autre de la limite Jurassique – Crétacé sont communs dans les différents bassins du domaine téthysien (Chitinoidella, calpionelles, Saccocoma, protoglobigérines, radiolaires A). Les Globochaete et les calcisphères paraissent par contre mieux adaptés à des conditions écologiques locales qui n’étaient peut-être pas celles de ce secteur de l’Iran, sans exclure les biais de la préservation des microfossiles, notamment dans la coupe de Kolur, localement affectée par des failles.
Published: 2012
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35. Early Berriasian ammonites from Shal, Talesh region (NW Alborz Mountains, Iran)

Author: Mohamed Benzaggagh, Kazem Seyed-Emami, Fabrizio Cecca, Johann Schnyder, Mahmoud Reza Majidifard, Mohammed Mohammadi Monfared, Centre de recherche sur la Paléobiodiversité et les Paléoenvironnements (CR2P), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), School of Mining Engineering, University College of Engineering, University of Tehran, Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Faculté des Sciences, Département de Géologie, Université Moulay Ismail (UMI), Geological Survey of Iran, Department of Geology, University of Esfahan, and Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)
Subjects: Ammonite, 010506 paleontology, biology, Fauna, Berriasella, Paleontology, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Biostratigraphy, 010502 geochemistry & geophysics, biology.organism_classification, 01 natural sciences, language.human_language, Cretaceous, Taxon, language, Taxonomy (biology), North african, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology, Geology, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: International audience; An early Berriasian (Berriasella jacobi Zone) ammonite fauna is described for the first time from the Alborz Mountains in northwest Iran. It has been collected from a section located near the village of Shal (Talesh region); in addition to rare phylloceratids, lytoceratids and Neolissoceras, the majority of ammonites belong to the neocomitid subfamily Berriasellinae. With the exception of a new genus and species, Taleshites fuersichi, these taxa are common in European and North African Tethyan successions. Associated calpionellids confirm the early Berriasian age of the ammonite-bearing levels.
Published: 2012
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36. Paleocene-Eocene Thermal Maximum impacts on terrestrial environments. Insights from the organic matter evolution in the Vasterival section (Dieppe-Hampshire Basin, France)

Author: Sylvain Garel, Johann Schnyder, Jérémy Jacob, Mohammed Boussafir, Christian Dupuis, Jean-Yves Storme, Iakovleva, Alina I., Emile Roche, Florence Quesnel, Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre d'Orléans (ISTO), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS), GFA - Polytech Mons, Université de Mons-Hainaut, FUNDP, UCL, Laboratory of Paleofloristics, Geological Institute, Russian Academy of Sciences [Moscow] (RAS), Laboratoire de Paléontologie Végétale, Université de Liège, POTHIER, Nathalie, and Université de Tours-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDE.MCG] Environmental Sciences/Global Changes, [SDE.MCG]Environmental Sciences/Global Changes, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, [SDU.ENVI] Sciences of the Universe [physics]/Continental interfaces, environment
Abstract: International audience; The Paleocene-Eocene Thermal Maximum (PETM, 55.8 Ma [1]) is regarded as one of the most rapid global warming of the Cenozoic era, with temperature increase of 4-8°C in about 10-20 ka [2]. Thus, it is often proposed as a potential analogue of future climatic conditions expected in the IPCC screenplays. The PETM is recorded in both marine and continental deposits by an abrupt negative Carbon Isotope Excursion (CIE) associated with other sedimentary and biological anomalies. The consequences of the PETM on terrestrial environments are less documented than in marine ones. This limits our regional- and global-scale understanding of the impact of such a climate change on continents and the associated response of ecosystems. This study focuses on the Vasterival section (Seine- Maritime, Upper Normandy) located in the southern part of the Dieppe-Hampshire Basin, in which the PETM is attested by a negative 13Corg shift in the organic matter (OM), and confirmed by the stratigraphic record in this locality belonging to the Cap dAilly composite section [3]. The 2 m thick section, which presents a notably well preserved OM, is mainly constituted by terrestrial sediments from lacustrine to coastal swamp environments, and in which OM-poor clays are followed by OM-rich clays, centimetric lignite beds and clays with roots evidences. The uppermost part of the section is constituted by 50 cm thick lagoonal clay with shell debris that records the Apectodinium acme. Global organic geochemical, palynofacies and isotopic analyses were performed on thirty samples. The total organic carbon of this section is ranging from 0.5 % for OM-poor-clays to 45 % for lignite levels. Hydrogen Index (from 6 to 210 mg HC/g TOC), Oxygen Index (from 80 to 630 mgCO2/g TOC) and Tmax values (from 410 to 430°C) show that the OM is of Type III (terrestrial higher plants), and immature. These results are reinforced by palynofacies observations that show a large amount of ligno- cellulosic phytoclasts in most of the samples. In the uppermost shale the presence of many Apectodinium species would suggest the continuity of the PETM in marine deposits. Thus, the continental deposits would represent a time interval that includes the uppermost Paleocene and the basal part of the PETM. Lipid biomarkers extracted from twenty five samples were quantified and their hydrogen and carbon isotopic composition were determined by GC-irMS. Important changes in palynofacies, biomarker assemblages and compound-specific isotopic data are coincident with the CIE onset interval. This is consistent with an important environmental modification in the Vasterival area during the Early Eocene that could be linked to the PETM climatic change. References [1] Aubry, M. P., Ouda, K., Dupuis, C ., Berggren, W. A., Van Couvering, J A., and the Members of the Working Group on the Paleocene/Eocene Boundary, 2007. The Global Standard Stratotype-section and Point (GSSP) for the base of the Eocene Series in the Dababiya section (Egypt). Episodes 30 (4): 271-286. [2] Zachos, J. C., Pagany, N., Sloan, L., Thomas, E., Billups, K., 2001. Trends, rythms, and aberrations in global climate 65 Ma to Present. Science 292: 686 693. [3] Dupuis, C., Steurbaut, E., De Coninck, J. and Riveline, J., 1998. The Western Argiles à Lignites facies. In: M. Thiry and C. Dupuis (Eds.), The Paleocene/Eocene boundary in Paris basin: the Sparnacian deposits. Field trip guide. ENSMP Mém. Sc. De la Terre, 34, 60-71.
Published: 2011

37. Paleocene-Eocene Thermal Maximum consequences on terrestrial environments. Insights from the evolution of organic matter in the Vasterival section (Dieppe-Hampshire Basin, France)

Author: Sylvain Garel, Johann Schnyder, Jérémy Jacob, Mohammed Boussafir, Christian Dupuis, Jean-Yves Storme, Johan Yans, Iakovleva, Alina I., Emile Roche, Claude Le Milbeau, Florence Quesnel, Ricordel-Prognon, Caroline, Paléobiodiversité et paléoenvironnements, Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Institut des Sciences de la Terre d'Orléans (ISTO), Université de Tours-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Géologie GFA, Université de Mons-Hainaut, FUNDP, UCL, Fondation Universitaire Notre Dame de la Paix (FUNDP), Facultés Universitaires Notre Dame de la Paix (FUNDP), Geological Institute, Russian Academy of Sciences [Moscow] (RAS), Institut de Chimie de Strasbourg, Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), and Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.STU] Sciences of the Universe [physics]/Earth Sciences, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences
Abstract: The Paleocene-Eocene Thermal Maximum (PETM, 55.8 Ma, Aubry et al, 2007) is regarded as one of the most rapid global warming of the Cenozoic era, with temperature increase of 4-8°C in about 10-20 ka. Thus, it is often proposed as a potential analogue of future climatic conditions expected in the screenplays provided by the International Panel on Climate Change (IPCC). The PETM is recorded in both marine and continental deposits by an abrupt negative Carbon Isotope Excursion (CIE) associated with other sedimentary and biological anomalies. The consequences of the PETM in terrestrial environments are less documented than in marine ones. This limits our regional- and global-scale understanding of the impact of such a climate change on continents and the ecosystems response. This study focuses on the Vasterival section (Seine-Maritime, Upper Normandy) located in the southern part of the Dieppe-Hampshire Basin, in which the PETM is recorded in the organic matter (OM) by the negative shift in δ13Corg of the CIE, and confirmed by the stratigraphic record in this locality belonging to the Cap d'Ailly composite section (Dupuis et al., 1998). The 2 m thick section, which presents a notably well preserved OM, is mainly constituted by terrestrial sediments from lacustrine to coastal swamp environments and in which OM-poor clays are followed by OM-rich clays, centimetric lignite beds and clays with roots evidences. The uppermost part of the section is constituted by 50 cm thick lagoonal clay with shell debris that records the Apectodinium acme. Global organic geochemical, palynofacies and isotopic analyses were performed on thirty samples. The total organic carbon of this section is ranging from 0.5 % for OM-poor-clays to 45 % for lignite levels. Lipid biomarkers extracted from twenty five samples were quantified and their hydrogen and carbon isotopic composition were determined by GC-irMS. Important changes in palynofacies, biomarker assemblages and compound-specific isotopic data are coincident with the CIE onset interval. This is consistent with an important environmental modification in the Vasterival area during the Early Eocene that could be linked to the PETM climatic change.
Published: 2011

38. Instability structures, synsedimentary faults and turbidites, witnesses of a Liassic seismotectonic activity in the Dauphiné Zone (French Alps): A case example in the Lower Pliensbachian at Saint-Michel-en-Beaumont

Author: Johann Schnyder, Pierre-Yves Collin, Bruno Galbrun, Isabelle Rouget, François Baudin, Françoise Bergerat, Anne-Céline Ganzhorn, Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur la Paléobiodiversité et les Paléoenvironnements (CR2P), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)
Subjects: geography, geography.geographical_feature_category, Rift, 010504 meteorology & atmospheric sciences, Bouma sequence, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Fault (geology), 010502 geochemistry & geophysics, 01 natural sciences, Paleontology, Geophysics, Tension (geology), Marl, Sedimentary rock, Extensional tectonics, Graded bedding, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology, Geology, Seismology, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Earth-Surface Processes
Abstract: Instability structures, synsedimentary faults and turbidites have been studied in the Lower Pliensbachian succession of Saint-Michel-en-Beaumont, belonging to the Taillefer block, an ancient half-graben emplaced during the Liassic Tethyan rifting. Geometrical and mechanical analyses demonstrate that the instability structures occurred thanks to movements along spineless synsedimentary normal faults, when the turbiditic and limestone layers were already case-hardened and partly fractured by tension gashes even when the mudstones were still unlithified. Both the tension gashes and the synsedimentary faults are homogeneous in strike with the major regional faults and are in good agreement with the regional direction of extension for this period. The characters of the turbiditic beds, with erosive base, graded bedding, and incomplete Bouma sequence, are in favour of a seismic origin. Instability structures, spineless synsedimentary faults and turbiditic inflows are thus considered as seismites and interpreted as the result of high seismicity periods including some events with M > 5 in the general extensive ambiance of the Liassic Tethyan rifting. The analysis of the geometrical relationships between all these sedimentary features allows to distinguish the successive stage of occurrence of an instability structure, from the sedimentation of alternating marls and limestones, and sudden turbiditic inflows, then early case-hardening of the turbidites, until the important seismotectonic event generating the spineless normal faults, themselves triggering the fall of indurated blocks and locally the forming of breccias. The Ornon Fault, which constitutes the border of the Taillefer block, 15 km eastward, played a major role during the Liassic sedimentation and may represent the major seismic fault related to the seismites occurrence in the Beaumont basin.
Published: 2011
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39. Paleocene-Eocene Thermal Maximum consequences on terrestrial environments. Insights from the evolution of organic matter in the Vasterival section (Paris Basin, France)

Author: Sylvain Garel, Johann Schnyder, Jérémy Jacob, Mohammed Boussafir, Christian Dupuis, Jean-Yves Storme, Johan Yans, Claude Le Milbeau, Florence Quesnel, Paléobiodiversité et paléoenvironnements, Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre d'Orléans (ISTO), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS), Géologie GFA, Université de Mons-Hainaut, FUNDP, UCL, Fondation Universitaire Notre Dame de la Paix (FUNDP), Facultés Universitaires Notre Dame de la Paix (FUNDP), Institut de Chimie de Strasbourg, Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Arregros, Marielle, Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), and Université de Tours-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.STU] Sciences of the Universe [physics]/Earth Sciences, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences
Abstract: The Paleocene-Eocene Thermal Maximum (PTEM) is often proposed as an analogue of future climatic conditions expected in the screenplays provided by the International Panel on Climate Change (IPCC). The PETM is characterized by a 3°C estimated rise of global temperature and is recorded in marine and terrestrial deposits by a carbon isotopic excursion (CIE). Most of published works related to this paleoclimatic crisis focus on marine sediments. This presently limits our regional- and global-scale understanding of the impact of such a climate change in terrestrial environments and the deciphering of the ecosystems response. This study focuses on the Vasterival section (Seine-Maritime, Upper Normandy, France) located in the NW of the Paris Basin, and in which the PETM is recorded in the organic matter (OM) by the d13C negative shift of the CIE. The 2m thick section is mainly constituted by terrestrial sediments deposited in fluvial and lacustrine to coastal swamp environments and in which OM-poor shales are followed by OM-rich shales, centimetric lignite beds, paleosols, and two beds containing carbonate nodules. The uppermost part of the section is constituted by a 50cm thick shale with shell debris that attests to a lagoonal influence. This section is constantly refreshed by a little stream, thus facilitating the sampling of fresh material, notably a well preserved OM. Global geochemical, palynofacies and isotopic analyses focused on thirty samples, and seventeen lipid extracts were analyzed by gas chromatography-mass spectrometry. The association of these methods allows us to characterize the OM of the different deposits encountered. Sulfur contents are particularly high (up to 15% of S), thus indicating an euxinic depositional environment. Total Organic Carbon (TOC) varies from 1% for OM-poor shales and paleosols up to 45% for lignite levels. From Hydrogen Index (from 6 to 210 mg HC/g TOC), Oxygen Index (from 80 to 630 mgCO2/g TOC) and Tmax values (from 410 to 430°C) we can show that the OM is of Type III (terrestrial higher plants), and immature. These results are reinforced by palynofacies observations, as a large amount of ligno-cellulosic phytoclastes is present in most of the samples. In the uppermost shale the continuity of the PETM in marine deposits can be inferred by the presence of many Apectodinium species. Thus, the terrestrial deposits would represent a time interval that includes the uppermost Paleocene and the basal part of the PETM. Molecular analyses underline the contribution of terrestrial higher plants by the presence of long chain n-alcanes with odd-over-even predominance, and Onocerane I, a compound rarely detected in sediments, attests to a contribution of lycopods or plants affiliated to the genus Pseudofagus. A notable bacterial contribution is also inferred by the presence of hopanoids in the extracts. This is confirmed by organic petrography results that reveal alginites laminae, often interpreted as a witness of well-preserved bacterial and/or algal mats. From our early results we show that significant environmental changes are recorded during the CIE. High resolution analyses and complementary analyses (X-ray tomography, isotopic, thin section petrography...) are currently in progress. This approach is complemented by a sedimentological study and they both will be extended to other sites along a transect crossing the terrestrial to lagoonal paleoenvironments of the Paleocene-Eocene transition in the Paris Basin. They aim at defining possible spatial heterogeneities in the PETM's impact on terrestrial environments and ecosystems, at a regional scale. To the west of the transect, the Cap d'Ailly sections and core will be first studied, because of their position very close to the Vasterival site, the relative richness in outcrops and the continuation of the PETM recorded in around 10m of lagoonal deposits, comprising various facies often OM rich: tidal fine sand, silt and clay, shell beds, and few cemented carbonate beds.
Published: 2010

40. Occurrence of organic-matter-rich beds in Early Cretaceous coastal evaporitic setting (Dorset, UK): a link to long-term palaeoclimate changes?

Author: François Baudin, Jean-François Deconinck, Johann Schnyder, Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Biogéosciences [UMR 6282] (BGS), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre de Paris ( iSTeP ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ), Biogéosciences [Dijon] ( BGS ), Université de Bourgogne ( UB ) -AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique ( CNRS ), Biogéosciences [UMR 6282] [Dijon] (BGS), and Centre National de la Recherche Scientifique (CNRS)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement
Subjects: 010506 paleontology, [SDE.MCG]Environmental Sciences/Global Changes, Climate change, Jurassic, [ SDU.STU.ST ] Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, 010502 geochemistry & geophysics, 01 natural sciences, Palynofacies, Deposition (geology), Cretaceous, Paleontology, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, 14. Life underwater, Cove, Sea level, 0105 earth and related environmental sciences, Total organic carbon, geography, geography.geographical_feature_category, 15. Life on land, [ SDU.STU.GC ] Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Botryococcus-type algae, [ SDE.MCG ] Environmental Sciences/Global Changes, Oceanography, 13. Climate action, [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, Purbeckian facies, Organic matter, Bay, Geology
Abstract: 11 pages; International audience; In Dorset (southern U.K.), the Durlston Bay and Lulworth Cove sections expose lowermost Cretaceous coastal marine and non-marine partly evaporitic sediments (the so-called Purbeckian facies). An interval with organic matter (OM)-rich layers is recognized in both sections. This OM-rich interval is 20 m thick in the middle of the Durlston Bay section. Within these beds, a large OM accumulation is recorded, with total organic carbon (TOC) of up to 8.5 wt%. High hydrogen index (HI) values (up to 956 mgHC/gTOC) point to a Type I OM, generally considered as derived from algal-bacterial biomass. This contrasts with the OM present in the underlying and overlying intervals, displaying in general lower TOC and HI values, and consisting of degraded algal-bacterial material with higher proportions of terrestrial OM. This organic-rich accumulation can be interpreted as a period of enhanced primary productivity within coastal lagoonal/lacustrine settings at times of low sea level. It could also correspond to increasingly reducing waters. The OM distribution found in Dorset correlates well with existing long-term palaeoclimatic patterns, i.e. a latest Jurassic (late Tithonian)-Early Cretaceous (early Berriasian) semi-arid climate replaced during the middle-late Berriasian by a more humid climate. This pattern is recorded elsewhere on both margins of the Tethys, indicating a widespread climate change. In Dorset, deposition of OM-rich beds occurs exactly at the transition between these two climate regimes, probably during the first increase in humidity, which led to enhanced freshwater supply into coastal lakes and lagoons. This suggests a direct or indirect climate control on local development of primary productivity and/or anoxia/ dysoxia within restricted shallow coastal water masses. The proposed environmental model links OM production and preservation with a changing, climate-driven, hydrological regime.
Published: 2009
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41. Depositional environments and characterisation of the organic matter of the Lower Mundeck Formation (Barremian ?-Aptian) of the Kribi-Campo sub-basin (South Cameroon) : Implications for petroleum exploration

Author: Jean-Claude Makong, Guy Martin Abolo, Marie-Joseph Ntamak-Nida, François Baudin, Johann Schnyder, Paul Bertrand Komguem, Département des Sciences de la Terre, Université de Douala, Laboratoire de tectonique (LT), Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), National Hydrocarbon Corporation, Yaoundé, Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Cergy Pontoise (UCP), and Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS)
Subjects: Maturity (geology), geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Aptian, Alluvial fan, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Geology, 010502 geochemistry & geophysics, 01 natural sciences, Cretaceous, Palynofacies, Sedimentary depositional environment, Paleontology, Source rock, Facies, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Earth-Surface Processes
Abstract: Lacustrine and alluvial fan facies from the Lower Mundeck Formation (Barremian ?–Aptian) cropping out in the southern part of the Kribi-Campo sub-basin (Cameroon) have been characterised for their oil potential, using both Rock-Eval pyrolysis and palynofacies analyses. The shaly facies show good potential as oil-prone source rock, with TOC content around 4.4% and some intervals with an optimum potential to yield 45 kg hydrocarbons/t of rock. Along the studied outcrops, these organic-rich facies represent approximately a third of the total thickness. Although the studied samples come out from immature thin organic-rich beds within sand dominated beds, it is reasonable to think that these oil-prone facies increase in thickness and maturity in the offshore area, making this part of the southern margin of Cameroon of special interest for petroleum exploration.
Published: 2008
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42. Environmental change during the Early Cretaceous in the Purbeck-type Durlston Bay section (Dorset, Southern England): a biomarker approach

Author: Armelle Riboulleau, Vincent Lefebvre, Jean-François Deconinck, Laurent Riquier, François Baudin, Johann Schnyder, Processus et bilan des domaines sédimentaires ( PBDS ), Université de Lille, Sciences et Technologies-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de tectonique ( LT ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Cergy Pontoise ( UCP ), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique ( CNRS ), Biogéosciences [Dijon] ( BGS ), AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Université de Bourgogne ( UB ) -Centre National de la Recherche Scientifique ( CNRS ), Processus et bilan des domaines sédimentaires (PBDS), Université de Lille, Sciences et Technologies-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de tectonique (LT), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Biogéosciences [UMR 6282] (BGS), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Biogéosciences [UMR 6282] [Dijon] (BGS), and Centre National de la Recherche Scientifique (CNRS)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement
Subjects: 010504 meteorology & atmospheric sciences, Environmental change, [SDE.MCG]Environmental Sciences/Global Changes, Botryococcus, 010502 geochemistry & geophysics, [ SDU.STU.ST ] Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, 01 natural sciences, [ SDE.MCG.CPE ] Environmental Sciences/Global Changes/domain_sde.mcg.cpe, Bottom water, Sterane, chemistry.chemical_compound, Geochemistry and Petrology, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, 0105 earth and related environmental sciences, Total organic carbon, biology, Ecology, 15. Life on land, biology.organism_classification, [SDE.MCG.CPE]Environmental Sciences/Global Changes/domain_sde.mcg.cpe, [ SDU.STU.GC ] Sciences of the Universe [physics]/Earth Sciences/Geochemistry, 6. Clean water, Cretaceous, Palynofacies, [ SDE.MCG ] Environmental Sciences/Global Changes, chemistry, 13. Climate action, [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, Bay, Geology
Abstract: 20 pages; International audience; The Purbeck-type section (Durlston Bay, Dorset, UK) exhibits littoral lagoonal to lacustrine facies. It shows a gradual climatic/environmental change from semi-arid conditions associated with evaporites at the Jurassic–Cretaceous transition, to a more humid climate at the end of the Berriasian. Though generally organic-poor (total organic carbon, TOC
Published: 2007
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43. Conjunctive use of spectral gamma-ray logs and clay mineralogy in defining late Jurassic-early Cretaceous palaeoclimate change (Dorset, U.K.)

Author: François Baudin, Alastair Ruffell, Johann Schnyder, Jean-François Deconinck, Paléobiodiversité et paléoenvironnements, Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ), School of Geography, Queen's University, Biogéosciences [Dijon] ( BGS ), AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Université de Bourgogne ( UB ) -Centre National de la Recherche Scientifique ( CNRS ), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Queen's University [Kingston, Canada], Biogéosciences [UMR 6282] [Dijon] (BGS), Centre National de la Recherche Scientifique (CNRS)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement, Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Biogéosciences [UMR 6282] (BGS), and Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010506 paleontology, Jurassic-Cretaceous boundary, [SDE.MCG]Environmental Sciences/Global Changes, Spectral gamma ray, chemistry.chemical_element, Structural basin, 010502 geochemistry & geophysics, Oceanography, Palaeoclimate, [ SDU.STU.ST ] Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, 01 natural sciences, Paleontology, [SDE.MCG.CG]Environmental Sciences/Global Changes/domain_sde.mcg.cg, Dorset, Kaolinite, Organic matter, [ SDE.MCG.CG ] Environmental Sciences/Global Changes/domain_sde.mcg.cg, [ SDU.STU.MI ] Sciences of the Universe [physics]/Earth Sciences/Mineralogy, Ecology, Evolution, Behavior and Systematics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Earth-Surface Processes, Total organic carbon, chemistry.chemical_classification, Thorium, Clay mineralogy, Cretaceous, [ SDE.MCG ] Environmental Sciences/Global Changes, Source rock, chemistry, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, Purbeck facies, [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, [ SDU.STU.CL ] Sciences of the Universe [physics]/Earth Sciences/Climatology, Clay minerals, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology, Geology, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
Abstract: Detrital clay mineralogy is controlled by weathered source rock, climate, transport and deposition that in turn influence the spectral gamma-ray (SGR) response of resultant sediments. Whilst a palaeoclimate signal in clay mineralogy has been established in some ancient successions, the SGR response remains contentious, largely because the data sets have yet to be collected at the same or appropriate vertical scales to allow comparison. In addition, the influence of organic matter on SGR is not always considered. Here, we present clay mineralogical, total organic carbon (TOC) and SGR analyses from the late Jurassic and early Cretaceous of the Wessex Basin, a period of previously documented palaeoclimate change. The aim of this paper is to estimate the sensitivity of SGR as palaeoclimatic tool, SGR and clay mineral data having been collected at the same sample points, making this one of the most rigorous comparison of clay mineral and SGR to date. Overall, the correlation between high thorium/potassium or thorium/uranium and kaolinite associated with a well-established palaeoclimate change shows that elevated thorium may be used as a proxy for humid palaeoweathering, as suggested by few previous studies.
Published: 2006
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44. Tectonosedimentary deformations and processes in semi-indurated marine sediments : the Permi-Triassic basins of Northern Europe (UK) and the intra-mountain basin of Tabernas (Spain)

Author: Laborde-Casadaban, Marine, Institut des Sciences de la Terre de Paris (iSTeP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris VI, Catherine Homberg, Johann Schnyder, and Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: Seismites, Liquéfaction, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Liquéfaction des sédiments meubles, Bassin de Tabernas, Dépôt de transport de masse, Groupe de Penarth, Mass transport deposit, Soft sediment deformation, Séismites
Abstract: The aim is to study the sedimentary structures of deformation produced by liquefaction in subsurface of marine sediments (soft sediment deformations) during seismic events. A characterization of different levels of seismites is carried out in order to (1) establish links between the formation of SSDs and the regional tectonics with the time of destabilization using structural directions of deformation; (2) to discuss the impact of lithology on the shape and location of deformation structures in the sedimentary pile. The characterization of SSDs is realized from: (1) field observations and (2) statistical measurements of the direction of structures on objects of variable dimensions. The first studied case concerns the characterization of the SSDs that affect the Penarth group (Triassic-Jurassic boundary) deposits in the British Isles at the beginning of the break-up phase of the Pangea. The second example present the characterization of upstream areas of four major mass transport deposits, located in the intramontane basin of Tabernas, in the Betic Cordilleras (Spain). Sediment lithology and induration rates with depth, have a strong impact on the type of observed deformation structures. The parameters that encourage the triggering of the gravity destabilization above a liquefied level are (1) a low sedimentary induration rate which does not limit the liquefaction process (2) a high liquefaction duration which requires a high magnitude of the seismic event (3) the absence of faults which cross the liquefied level and can anchor the deformation in the underlying bed by forming relief.; Le but de cette thèse est d'étudier les structures sédimentaires de déformations produites par liquéfaction en subsurface des sédiments marins (soft sediment deformations) lors d'événements sismiques. Une caractérisation de différents niveaux de séismites est menée afin de mettre en relation la formation des SSDs et la tectonique régionale au moment de la déstabilisation à l'aide des directions de structures, et de discuter de l'impact de la lithologie sur la forme et la localisation des SSDs dans la pile sédimentaire. Ce travail est réalisé à partir d'observations de terrain et de mesures statistiques de la direction des structures sur des objets de dimensions variables. Le premier exemple s'est portée sur les SSDs qui affectent les dépôts du Penarth group (limite Trias-Jurassique) dans les îles Britanniques au début de la phase de dislocation de la Pangée. Le second exemple s'est appliqué à la caractérisation des parties amont de quatre grands mass transport deposits présents dans le bassin néogène de Tabernas, (cordillères Bétiques, Espagne). Cette étude a mis en évidence le lien très fort entre la déformation de surface et la tectonique et l'intérêt d'étudier ces objets pour mieux définir le contexte du bassin au moment de la déstabilisation. La lithologie du sédiment et son taux d'induration ont un impact fort sur le type de SSDs observées. Les paramètres favorisant le déclenchement de la déstabilisation gravitaire au-dessus d'un niveau liquéfié sont 1) un faible taux d'induration sédimentaire 2) un temps de liquéfaction important et des fortes magnitudes de séisme 3) l'absence de failles qui traversent le niveau liquéfié susceptibles d'ancrer la déformation.
Published: 2017

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