Author: "Research School of Earth Sciences [Canberra] (RSES)" - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"Research School of Earth Sciences [Canberra] (RSES)"' showing total 148 results

Start Over Author "Research School of Earth Sciences [Canberra] (RSES)"

148 results on '"Research School of Earth Sciences [Canberra] (RSES)"'

1. Preservation of Permian allanite within an Alpine eclogite facies shear zone at Mt Mucrone, Italy: Mechanical and chemical behavior of allanite during mylonitization

Author: T. B. Thomsen, Carl Spandler, Martin Engi, Philippe Goncalves, Bénédicte Cenki-Tok, Emilien Oliot, Daniele Regis, Daniela Rubatto, Alfons Berger, Paola Manzotti, Martin Robyr, Emilie Janots, Institute of Geological Sciences [Bern], University of Bern, 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), Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), University of Copenhagen = Københavns Universitet (KU), Minéralogie et environnements, 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)-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), School of Earth and Environmental Sciences [Australia], James Cook University (JCU), Financial support from Swiss National Fund for our work in the Western Alps (Grants 200020-109637, 200021-117996/1). The electron microprobe at the University of Bern is also partly funded by SNF (Grant 200021-103479/1)., Institute of Geological Sciences, 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 ), Laboratoire Chrono-environnement ( LCE ), Université Bourgogne Franche-Comté ( UBFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Research School of Earth Sciences [Canberra] ( RSES ), Australian National University ( ANU ), University of Copenhagen ( KU ), Institut des Sciences de la Terre ( ISTerre ), 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 ) -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 ), and James Cook University, School of Earth and Environmental Sciences
Subjects: 010504 meteorology & atmospheric sciences, Shear zone, Clinozoisite, Geochemistry, Metamorphism, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Allanite, Geochemistry and Petrology, [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology, Metamorphic facies, 0105 earth and related environmental sciences, [ SDU.STU.GM ] Sciences of the Universe [physics]/Earth Sciences/Geomorphology, Western Alps, Geology, Epidote, U-Th-Pb ages, Mt Mucrone, engineering, Eclogite, Sesia zone, Mylonite
Abstract: International audience; This study addresses the mechanical and chemical behavior of allanite during shear zone formation under high-pressure metamorphism. Understanding physico-chemical processes related to the retention or resetting of Pb isotopes in allanite during geological processes is essential for robust petrochronology. Dating of allanite in meta-granodiorite showing variable amounts of strain (from an undeformed protolith to mylonite) at Monte Mucrone (Sesia Zone, NW Italy) gave surprising results. Based on structural and petrographic observations the shear zones at Mt Mucrone are Alpine, yet allanite located within an eclogite facies mylonite yielded Permian ages (208Pb/232Th average age: 287 ± 7 Ma). These mm-sized allanite grains are rimmed by an aggregate of coarse-grained garnet + phengite, thought to derive from former epidote. These aggregates were immersed in a weak matrix that experienced granular flow, and they were thus chemically and mechanically shielded during Alpine mylonitization. In undeformed samples (8a and 8b), two populations of epidote group minerals were found. Allanite forms either coronas around Permian monazite or individual grains with patchy zoning. Both types yield Permian ages (208Pb/232Th age: 291 ± 5 Ma). On the other hand, grains of REE-rich clinozoisite of Cretaceous age are found in undeformed rocks. These grains appear as small fragments with embayed surface outlines and minute satellites or rims around Permian allanite. These (re)crystallized grains are Sr-rich and show mosaic zoning. These results indicate that allanite crystals retained their chemical and isotopic characteristics, and thus their Permian age, as a result of strong strain partitioning between the epidote group porphyroclasts and the eclogite facies matrix in HP-mylonites. The observed partial mobilization of Pb isotopes, which lead to the Cretaceous-aged rims or grains in undeformed samples was facilitated by (re)crystallization of allanite and not by mere Pb diffusion alone under the HP conditions.
Published: 2011
Full Text: View/download PDF

2. The Southern Ocean Radiolarian (SO-RAD) dataset: a new compilation of modern radiolarian census data

Author: K.-A. Lawler, G. Cortese, M. Civel-Mazens, H. Bostock, X. Crosta, A. Leventer, V. Lowe, J. Rogers, L. K. Armand, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Graduate School of Integrated Arts and Sciences, Hiroshima University, 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), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010506 paleontology, QE1-996.5, 010504 meteorology & atmospheric sciences, Biogeography, Species diversity, Sediment, Geology, Census, 01 natural sciences, Environmental sciences, Taxon, Geography, Oceanography, [SDU]Sciences of the Universe [physics], General Earth and Planetary Sciences, GE1-350, 14. Life underwater, Reference dataset, 0105 earth and related environmental sciences
Abstract: Radiolarians (holoplanktonic Protozoa) preserved in marine sediments are commonly used as palaeoclimate proxies for reconstructing past Southern Ocean environments. Generating reconstructions of past climate based on microfossil abundances, such as radiolarians, requires a spatially and environmentally comprehensive reference dataset of modern census counts. The Southern Ocean RADiolarian (SO-RAD) dataset includes census counts for 238 radiolarian taxa from 228 surface sediment samples located in the Atlantic, Indian and southwest Pacific sectors of the Southern Ocean. This compilation is the largest radiolarian census dataset derived from surface sediment samples in the Southern Ocean. The SO-RAD dataset may be used as a reference dataset for palaeoceanographic reconstructions, or for studying modern radiolarian biogeography and species diversity. As well as describing the data collection and collation, we include recommendations and guidelines for cleaning and subsetting the data for users unfamiliar with the procedures typically used by the radiolarian community. The SO-RAD dataset is available to download from doi.pangaea.de/10.1594/PANGAEA.929903 (Lawler et al., 2021).
Published: 2021
Full Text: View/download PDF

3. Nature of the crust beneath the islands of the Mozambique Channel: Constraints from receiver functions

Author: Laurent Michon, Guilhem Barruol, Hrvoje Tkalčić, Anthony Dofal, Fabrice R. Fontaine, Laboratoire GéoSciences Réunion (LGSR), Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris), Institut de Physique du Globe de Paris (IPGP (UMR_7154)), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Observatoire volcanologique et sismologique de martinique (OVSM), Institut de Physique du Globe de Paris (IPG Paris), Institut des Géosciences de l’Environnement (IGE), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Université de La Réunion (UR)-Institut de Physique du Globe de Paris, Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), and Institut de Physique du Globe de Paris
Subjects: geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Continental crust, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Geology, Crust, Volcanism, 010502 geochemistry & geophysics, 01 natural sciences, Paleontology, Mohorovičić discontinuity, Volcano, Receiver function, Archipelago, 14. Life underwater, Magmatic underplating, 0105 earth and related environmental sciences, Earth-Surface Processes
Abstract: International audience; Starting in May 2018, a volcano-tectonic crisis occurred in the vicinity of Mayotte, a volcanic island in the Comoros Archipelago in the Mozambique Channel. The origin of the volcanism but also the subsurface architecture and nature of the crust, remain unknown. Here, based on receiver function analyses that provide S-wave velocity profiles, we determine the depth of Mohorovičić discontinuity (Moho) and V P /V S ratios for volcanic islands in the Mozambique Channel. We propose that the crust beneath Mayotte and Juan de Nova islands is of continental nature, while it appears to be of oceanic origin beneath Europa and Grande Glorieuse islands. Our results suggest that Mayotte edifice grew on an isolated continental block abandoned during the Gondwana breakup and the opening of the Mozambique Channel. The continental crust is underlain by a thick (9-10 km) and fast layer, interpreted as magmatic underplating which may result from the 20-Myr-long duration of the volcanism. The new velocity model determined from the seismic station on Mayotte can be used to relocate the seismicity related to the ongoing volcano-tectonic crisis.
Published: 2021
Full Text: View/download PDF

4. Shear wave velocities across the olivine – wadsleyite – ringwoodite transitions and sharpness of the 410 km seismic discontinuity

Author: Jean-Philippe Perrillat, Benoît Tauzin, Julien Chantel, Julie Jonfal, Isabelle Daniel, Zhicheng Jing, Yanbin Wang, 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), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Unité Matériaux et Transformations - UMR 8207 (UMET), Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Center for Advanced Radiation Sources [University of Chicago] (CARS), and University of Chicago
Subjects: [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], [CHIM.MATE]Chemical Sciences/Material chemistry, Earth's mantle, Geophysics, kinetics, Space and Planetary Science, Geochemistry and Petrology, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Earth and Planetary Sciences (miscellaneous), seismic discontinuity, ringwoodite, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], olivine, wadsleyite
Abstract: International audience; The seismic signature of the 410-km seismic discontinuity is generally attributed to the olivine to wadsleyite polymorphic transformation. However, apparent discrepancies exist between seismic and experimental observations. Among those, the sharpness of the discontinuity as inferred from the reflectivity of seismic waves is difficult to reconcile with the gradual nature of the olivine to wadsleyite transformation predicted by phase equilibria. In this study, we explore the contribution of the phase transition kinetics to the sharpness of the discontinuity by performing X-ray diffraction and sound velocity measurements on (Mg,Fe)2SiO4 with an unprecedented time resolution as a function of the reaction progress. Our data document for the first time a transient velocity softening phenomenon and attenuation which we relate to the formation of a metastable spineloid phase. In the Earth's mantle this transformation mechanism would affect the elastic gradient within the olivine-wadsleyite two-phase loop, potentially creating a low-velocity layer; hence explaining the unique sharpness and reflectivity of the discontinuity.
Published: 2022
Full Text: View/download PDF

5. Experimental constraints on the differentiation of low-alkali magmas beneath the Tonga arc: Implications for the origin of arc tholeiites

Author: Chris W. Firth, Hugh St. C. O'Neill, Saskia Erdmann, Tracy Rushmer, Raul Brens, Simon Turner, Trevor H. Green, John Adam, Department of Earth and Planetary Sciences [North Ryde], Macquarie University, 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)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Magma - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (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), Research School of Earth Sciences [Canberra] (RSES), and Australian National University (ANU)
Subjects: Basalt, 010504 meteorology & atmospheric sciences, Tonga-Kermadec Tholeiite Crystal fractionation Experimental petrology, Partial melting, Geochemistry, Geology, engineering.material, 010502 geochemistry & geophysics, Dacite, 01 natural sciences, Basaltic andesite, [SDU]Sciences of the Universe [physics], 13. Climate action, Geochemistry and Petrology, engineering, Plagioclase, Phenocryst, Igneous differentiation, Amphibole, 0105 earth and related environmental sciences
Abstract: International audience; Hydrous melting experiments on a basaltic andesite from Late Volcano in the Tonga Arc were conducted at 900–1250 °C and 1 atm to 2.5 GPa, with a range of added H2O concentrations (0–9 wt%). These were used to constrain conditions of phenocryst precipitation in the basaltic andesite and to better understand the processes of magmatic differentiation beneath Tongan volcanoes. Comparison between the products of experiments and Tongan lavas indicates that basaltic andesites from Late crystallised plagioclase + augite + pigeonite ± orthopyroxene while water-saturated at comparatively low pressures (≤0.2 GPa) but high temperatures (≥1000 °C). Glasses produced at 950 °C and 0.2 GPa are similar in composition to dacites from neighbouring volcanoes, including Fonualei. This confirms previous interpretations of dacite magma genesis by crystal fractionation of plagioclase and clinopyroxene from basaltic andesite parent magmas, rather than by partial melting of lower crust. This produces decreases in Dy/Yb with increasing SiO2 without a role for amphibole, probably due to the high temperatures and low alkali concentrations involved. Tongan magmas are primarily tholeiitic, and their high water contents bring into question previous hypotheses that attribute the tholeiitic trend to low concentrations of magmatic H2O. Attributes inherited from the Tongan parent magmas, including low alkali concentrations, appear to drive tholeiitic differentiation, regardless of water content.
Published: 2019
Full Text: View/download PDF

6. Best practices for the use of meteorite names in publications

Author: Heck, Philipp R., Herd, Christopher, Grossman, Jeffrey N., Badjukov, Dmitry, Bouvier, Audrey, Bullock, Emma, Chennaoui-Aoudjehane, Hasnaa, Debaille, Vinciane, Dunn, Tasha L., Ebel, Denton S., Ferriere, Ludovic, Garvie, Laurence, Gattacceca, Jerome, Gounelle, Matthieu, Herd, Richard, Ireland, Trevor, Jacquet, Emmanuel, Macke, Robert J., McCoy, Tim, McCubbin, Francis M., Mikouchi, Takashi, Metzler, Knut, Roskosz, Mathieu, Smith, Caroline, Wadhwa, Meenakshi, Welzenbach-Fries, Linda, Yamaguchi, Akira, Zeigler, Ryan A., Zolensky, Michael, Yada, Toru, NASA Headquarters, Laboratoire de Sciences de la Terre (LST), 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), American Museum of Natural History, American Museum of Natural History (AMNH), Natural History Museum [Vienna] (NHM), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), 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), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Australian National University (ANU), Department of Earth and Planetary Science [Tokyo], Graduate School of Science [Tokyo], The University of Tokyo (UTokyo)-The University of Tokyo (UTokyo), Institut für Planetologie [Münster], Westfälische Wilhelms-Universität Münster (WWU), Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Center for Meteorite Studies [Tempe], Arizona State University [Tempe] (ASU), National Institute of Polar Research [Tokyo] (NiPR), Astromaterials Research and Exploration Science (ARES), NASA Johnson Space Center (JSC), NASA-NASA, Field Museum of Natural History [Chicago, USA], University of Chicago, Department of Earth and Atmospheric Sciences [Edmonton], University of Alberta, Vernadsky Institute of Geochemistry and Analytical Chemistry (GEOKHI), Russian Academy of Sciences [Moscow] (RAS), Bavarian Research Institute of Experimental Geochemistry and Geophysics (Bayerisches Geoinstitut), Universität Bayreuth, Carnegie Institution for Science, Department of Earth Sciences [Casablanca], Faculté des Sciences Aïn Chock [Casablanca] (FSAC), Université Hassan II [Casablanca] (UH2MC)-Université Hassan II [Casablanca] (UH2MC), Laboratoire Géochimie, Traçage Isotopique, Minéral et élémentaire - G-Time (Bruxelles, Belgium), Colby College, 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), Retired, Research School of Earth Sciences [Canberra] (RSES), Specola Vaticana/Vatican Observatory, Department of Mineral Sciences [Washington], Smithsonian Institution, Westfälische Wilhelms-Universität Münster = University of Münster (WWU), The Natural History Museum [London] (NHM), School of Geographical and Earth Sciences [Univ Glasgow], University of Glasgow, Planetary Science Institute [Tucson] (PSI), Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency [Sagamihara] (JAXA), 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), The University of Tokyo (UTokyo), 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), Laboratoire de minéralogie du Muséum National d'Histoire Naturelle (LMMNHN), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), The University of Tokyo, and Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)
Subjects: History, 010504 meteorology & atmospheric sciences, Best practice, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Library science, Généralités, 010502 geochemistry & geophysics, 01 natural sciences, Sciences de la terre et du cosmos, Geophysics, Meteorite, Space and Planetary Science, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: This document contains suggestions for best practices by authors who refer to meteorites in publications. It can also be taken as a guide for publishers in establishing guidelines for authors. The following best practices are recommended in addition to acknowledging the loaning institution or loaning individual (unless required otherwise). The main motivations are to: help ensure that research on meteorites is reproducible, prevent confusion in the literature, and enhance tracking of specimens and related data., SCOPUS: le.j, info:eu-repo/semantics/published
Published: 2019
Full Text: View/download PDF

7. Who's been using my burial mound? Radiocarbon dating and isotopic tracing of human diet and mobility at the collective burial site, Le Tumulus des Sables, southwest France

Author: Richard Armstrong, Jocelyne Desideri, Elsa Ciesielski, Ceridwen Boel, Rachel Wood, Audrey Bridy, Patrice Courtaud, Leslie Kinsley, Malte Willmes, Catherine J. Frieman, Rainer Grün, Stephen Eggins, Linda McMorrow, Antoine Chancerel, Hannah F. James, Maxime Aubert, Stewart Fallon, Ian Moffat, Ian S. Williams, Chemistry, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), De la Préhistoire à l'Actuel : Culture, Environnement et Anthropologie (PACEA), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), Ministère de la Culture (MC), Archéologie des Sociétés Méditerranéennes (ASM), Université Paul-Valéry - Montpellier 3 (UPVM)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC), Laboratoire d'archéologie préhistorique et anthropologie, Université de Genève (UNIGE), Flinders University [Adelaide, Australia], Austalian National University, Research School of Earth Sciences and Research School of Pacific and Asian Studies, and Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)
Subjects: Radiocarbon dating, 010506 paleontology, Archeology, Sépulture, Campaniforme, Tumulus, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, δ18O, Population, Néolithique, Géochimie isotopique, Bell beaker, 01 natural sciences, law.invention, Palaeodiet, Archéologie, stomatognathic system, law, ddc:550, Dents, 0601 history and archaeology, Datation, education, teeth, 0105 earth and related environmental sciences, education.field_of_study, 060102 archaeology, δ13C, fungi, Paléoalimentation, archaeology, Burial mound, 06 humanities and the arts, Archaeology, mobility, Isotopic tracing, Mobilité, Iron Age, Bioanthropologie, Period (geology), Geology, Chronology
Abstract: International audience; The burial mound of Le Tumulus des Sables, southwest France, contains archaeological artefacts spanning from the Neolithic to the Iron Age. Human remains have been found throughout the burial mound, however their highly fragmented state complicates the association between the burial mound structure and the archaeological material. Radiocarbon dating and isotopic analyses of human teeth have been used to investigate the chronology, diet and mobility of the occupants. Radiocarbon dating shows that the site was used for burials from the Neolithic to Iron Age, consistent with the range of archaeological artefacts recovered. δ 13 C and δ 15 N values (from dentine collagen) suggest a predominately terrestrial diet for the population, unchanging through time. 87 Sr/ 86 Sr (on enamel and dentine) and δ 18 O (on enamel) values are consistent with occupation of the surrounding region, with one individual having a δ 18 O value consistent with a childhood spent elsewhere, in a colder climate region. These results showcase the complex reuse of this burial mound by a mostly local population over a period of about 2000 years.
Published: 2019
Full Text: View/download PDF

8. Homo luzonensis : principales caractéristiques et implications pour l’histoire évolutionnaire du genre Homo

Author: Détroit, Florent, Mijares, Armand Salvador, Corny, Julien, Daver, Guillaume, Zanolli, Clément, Dizon, Eusebio, Robles, Emil, Grün, Rainer, Piper, Philip, Histoire naturelle de l'Homme préhistorique (HNHP), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Université de Perpignan Via Domitia (UPVD), University of the Philippines (UP System), Département Homme et environnement (H&E), Muséum national d'Histoire naturelle (MNHN), Laboratoire de paléontologie, évolution, paléoécosystèmes, paléoprimatologie (PALEVOPRIM ), Université de Poitiers-Centre National de la Recherche Scientifique (CNRS), De la Préhistoire à l'Actuel : Culture, Environnement et Anthropologie (PACEA), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), National Museum of the Philippines, Research School of Earth Sciences [Canberra] (RSES), and Australian National University (ANU)
Subjects: [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, [SHS.ANTHRO-BIO]Humanities and Social Sciences/Biological anthropology, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology
Abstract: International audience; La nouvelle espèce Homo luzonensis a été décrite en 2019 à partir d’un assemblage constitué de treize éléments fossiles découverts dans la grotte de Callao (île de Luzon, Philippines) en 2007, 2011 et 2015. La datation directe de deux de ces fossiles par les séries de l’uranium indique des âges minimums respectifs de 50 000 et 67 000 ans. Dans cette présentation, nous montrons que ces spécimens présentent une combinaison de caractéristiques morphologiques primitives (i.e. ressemblant à Australopithecus) et dérivées (i.e. ressemblant à Homo sapiens) qui diffère de celle rencontrée dans toute les autres espèces du genre Homo connues jusqu’alors, y compris H. floresiensis et H. sapiens. Les implications potentielles des caractéristiques primitives observées sur les os des mains et des pieds sur les capacités manipulatrices et locomotrices d’H. luzonensis sont discutées, ainsi que les hypothèses sur l’origine de ces caractéristiques et plus généralement du taxon H. luzonensis. Ces caractéristiques pourraient avoir été héritées directement d’hominines anciens tels Australopithecus ou H. habilis, inconnus jusqu’à présent hors d’Afrique, ou alternativement avoir été héritées d’H. erectus asiatiques (de Chine et / ou d’Indonésie) et, après avoir évolué sous certaines pressions de sélection propres à l’île de Luzon, « ressembler » aux conditions primitives observées dans la tribu des hominines. Si au regard du registre connu en Asie pour les hominines fossiles la seconde hypothèse semble actuellement la plus probable, l’une ou l’autre de ces hypothèses aurait des implications majeures sur notre compréhension de l’histoire évolutionnaire récente du genre Homo.
Published: 2021

9. Digital twin for human-machine interaction with convolutional neural network

Author: Hichem Snoussi, Fei Tao, Chuang Wang, Jiakun Li, Yingjun Deng, Tian Wang, Shaanxi University of Science and Technology, Beihang University (BUAA), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Laboratoire Informatique et Société Numérique (LIST3N), Université de Technologie de Troyes (UTT), Tianjin University (TJU), State Grid Beijing Maintenance Company, Laboratoire Modélisation et Sûreté des Systèmes (LM2S), and Université de Technologie de Troyes (UTT)-Université de Technologie de Troyes (UTT)
Subjects: 0209 industrial biotechnology, action recognition, business.industry, Computer science, Mechanical Engineering, Aerospace Engineering, convolutional neural network, 02 engineering and technology, Convolutional neural network, Digital twin, Computer Science Applications, 020901 industrial engineering & automation, Human machine interaction, 0202 electrical engineering, electronic engineering, information engineering, Action recognition, 020201 artificial intelligence & image processing, Artificial intelligence, Electrical and Electronic Engineering, Intelligent manufacturing system, business, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, human-machine interaction
Abstract: International audience; Digital twin (DT) technology aims to create a virtual model of a physical entity and efficiently analyze the intelligent manufacturing system. Based on the DT, human-machine interaction (HMI) is a typical application. Deep learning technology is employed in the digital twin to realize and strengthen HMI while analyzing the physical and virtual data. The convolutional neural network (CNN) is used for analyzing visual information. For dealing with the HMI task in DT, two CNN models, Visual Geometry Group Network (VGG) and Residual Network (ResNet), are adopted. Modified 3D-VGG and 3D-ResNet models are proposed in this paper, which is an improvement over existing VGG and ResNet models. The models focus on humans’ information in videos that are captured with the HMI system’s sensors. The information, which can be regarded as the digital twin data, includes the action and the position of the human skeleton. Additionally, the proposed models are end-to-end. The experiments show that both models perform well on the human motion recognition task. The model can effectively generate skeletal data from video data. With the generated information, the human and the machine can interact well with the aid of the digital twin data analysis.
Published: 2021
Full Text: View/download PDF

10. Unraveling one billion years of geological evolution of the southeastern Amazonia Craton from detrital zircon analyses

Author: Marco Antônio Leandro Silva, Janaína N. Ávila, Cristiano Lana, Francesco Narduzzi, Paul Yves Jean Antonio, E. S. Rego, Camille Rossignol, Lívia Teixeira, Pascal Philippot, Ricardo I.F. Trindade, Romário Almeida de Souza, Instituto de Astronomia, Geofisica e Ciencias Atmosfericas da Universidade de Sao Paulo (IAGCAUSP), Université de Sao Paulo, Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Géosciences Montpellier, Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Université des Antilles (UA)-Centre National de la Recherche Scientifique (CNRS), Universidade de Santo Amaro [São Paulo] (UNISA), Universidade Federal do Sul e Sudeste do Para (UNIFESSPA), Research School of Earth Sciences [Canberra] (RSES), and Australian National University (ANU)
Subjects: geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Large igneous province, Geochemistry, Greenstone belt, 15. Life on land, Structural basin, 010502 geochemistry & geophysics, 01 natural sciences, Thermal subsidence, Craton, Paleoarchean, [SDU]Sciences of the Universe [physics], General Earth and Planetary Sciences, Sedimentary rock, Geology, 0105 earth and related environmental sciences, Zircon
Abstract: International audience; Despite representing one of the largest cratons on Earth, the early geological evolution of the Amazonia Craton remains poorly known due to relatively poor exposure and because younger metamorphic and tectonic events have obscured initial information. In this study, we investigated the sedimentary archives of the Carajás Basin to unravel the early geological evolution of the southeastern Amazonia Craton. The Carajás Basin contains sedimentary rocks that were deposited throughout a long period spanning more than one billion years from the Mesoarchean to the Paleoproterozoic. The oldest archives preserved in this basin consist of a few ca. 3.6 Ga detrital zircon grains showing that the geological roots of the Amazonia Craton were already formed by the Eoarchean. During the Paleoarchean or the early Mesoarchean (
Published: 2021
Full Text: View/download PDF

11. On The Efficiency of P ‐Wave Coda Autocorrelation in Recovering Crustal Structure: Examples From Dense Arrays in the Eastern United States

Author: Benoit Tauzin, Hrvoje Tkalčić, Chuang Wang, Thanh-Son Pham, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), 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), European Project: 793824,NoLimit, 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: geography, geography.geographical_feature_category, transitional Moho, 010504 meteorology & atmospheric sciences, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Autocorrelation, P wave, Structure (category theory), autocorrelations, Sedimentary basin, 010502 geochemistry & geophysics, seismology, 01 natural sciences, Coda, Physics::Geophysics, Geophysics, sedimentary basins, Space and Planetary Science, Geochemistry and Petrology, receiver functions, Earth and Planetary Sciences (miscellaneous), Seismology, Geology, 0105 earth and related environmental sciences
Abstract: International audience; Due to a sharp contrast in elastic properties across the basement rocks of sedimentary basins (SBs), strong reverberations are generated during the passage of seismic waves. Traditional receiver function methods become inadequate for imaging crustal structure due to the existence of these strong reverberations. We investigate the feasibility of an autocorrelation technique to extract vertical component receiver functions from teleseismic earthquake data and the efficiency of the method to image the crustal architecture in presence of a SB. The method involves spectral whitening followed by autocorrelation and stacking in the depth domain. We show promising results when using temporary seismic networks in the eastern United States. Using synthetic and field‐data examples, we demonstrate that vertical autocorrelations are more efficient than classical radial receiver functions for interpretation purposes in an SB context. We also perform a joint analysis of the amplitudes on radial and vertical receiver functions for characterizing the thickness of the Mohorovičić discontinuity (Moho). We find that the Moho in the eastern United States is a transitional layer (up to 5‐km thick) instead of a sharp boundary. Further, we point out that it is challenging to unambiguously pick and interpret reflected phases on autocorrelations because of the effects of reverberations, cross‐mode contaminations, and a narrow frequency band limiting the resolution of velocity gradients. We therefore send a message of caution for future interpretations based on this technique.
Published: 2020
Full Text: View/download PDF

12. Rare earth element and neodymium isotope tracing of sedimentary rock weathering

Author: Alexander M Piotrowski, Edward T. Tipper, Patrick De Deckker, Germain Bayon, Kazuyo Tachikawa, Nicolas Freslon, Maude Thollon, Kwangchul Jang, Nathalie Vigier, Christina S. Larkin, Thibault Lambert, Géosciences Marines (GM), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Institute of Earth Surface Dynamics, University of Lausanne, Université de Lausanne = University of Lausanne (UNIL), Laboratoire d'océanographie de Villefranche (LOV), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de la Mer de Villefranche (IMEV), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Biogéosciences [UMR 6282] (BGS), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Division of Polar Paleoenvironment, Korea Polar Research Institute (KOPRI), Department of Earth Sciences [Cambridge, UK], University of Cambridge [UK] (CAM), 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), Unité de recherche Géosciences Marines (Ifremer) (GM), Institute of Earth Surface Dynamics, Université de Lausanne (UNIL), 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, Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Work funded through an IEF Marie Curie fellowship (SI-PALEO, Grant No. FP7-PEOPLE-2012-IEF 327778), by NERC Grant (NE/P011659/1) for research into sediment compositions of large rivers, by an Australian Research Council DP grant (DP0772180) for the collection of Australian river samples., University of Lausanne (UNIL), Centre de Recherches de Climatologie [UMR Biogéosciences] (CRC), 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)-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), Bayon, G [0000-0002-6791-4953], De Deckker, P [0000-0003-3003-5143], Jang, K [0000-0003-3777-2728], Tachikawa, K [0000-0002-9522-8600], and Apollo - University of Cambridge Repository
Subjects: 010504 meteorology & atmospheric sciences, sub-01, Mid-REE enrichment, Geochemistry, Silicate weathering, Weathering, Concavity index, engineering.material, Structural basin, 010502 geochemistry & geophysics, Geologic record, 01 natural sciences, Iron oxides, chemistry.chemical_compound, Geochemistry and Petrology, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [CHIM]Chemical Sciences, 0105 earth and related environmental sciences, geography, geography.geographical_feature_category, Sulphide weathering, Neodymium isotopes, Geology, 15. Life on land, World rivers, Silicate, Craton, chemistry, 13. Climate action, Carbonate weathering, engineering, Carbonate, Sedimentary rock, Pyrite
Abstract: Chemical weathering plays an important role in sequestering atmospheric CO2, but its potential influence on global climate over geological timescales remains debated. To some extent, this uncertainty arises from the difficulty in separating the respective contribution of sedimentary and crystalline silicate rocks to past weathering rates in the geological record; two types of rocks having presumably different impact on the long-term carbon cycle. In this study, we investigate the use of rare earth element (REE) and neodymium isotopes (εNd) in leached iron oxide fractions of river sediments for tracing the origin of weathered rocks on continents. A new index, called ‘concavity index’ (CI), is defined for measuring the degree of mid-REE enrichment in geological samples, which enables the determination of the source of iron oxides in sediments, such as seawater-derived Fe-oxyhydroxide phases, ancient marine Fe oxides derived from the erosion of sedimentary rocks, and recent secondary oxides formed in soils via alteration of crystalline silicate rocks or pyrite oxidation. Using this index, we demonstrate that the εNd difference between paired Fe-oxide and detrital fractions in river sediments (defined here as ∆εNd Feox-Det) directly reflects the relative contribution of sedimentary versus crystalline silicate rocks during weathering. While rivers draining old cratons and volcanic provinces display near-zero ∆εNd Feox-Det values indicative of dominant silicate weathering (0.5 ± 1.1; n = 30), multi-lithological catchments hosting sedimentary formations yield systematically higher values (2.7 ± 1.2; n = 44), showing that sedimentary rock weathering can be traced by the occurrence of riverine Fe oxides having more radiogenic Nd isotope signatures compared to detrital fractions. This assumption is reinforced by the evidence that calculated ∆εNd Feox-Det values agree well with previous estimates for carbonate and silicate weathering rates in large river basins. Examining the influence of climate and tectonics on measured Nd isotopic compositions, we find that ∆εNd Feox-Det is strongly dependent on temperature in lowlands, following an Arrhenius-like relationship that reflects enhanced alteration of silicate rocks and formation of secondary Fe oxides in warmer climates. In contrast, in high-elevation catchments, ∆εNd Feox-Det defines striking correlation with maximum basin elevation, which we also interpret as reflecting the intensification of silicate weathering and associated Fe oxide formation as elevation decreases, due to the combined effects of thicker soils and warmer temperature. Overall, our new findings are consistent with previous assertions that the alteration of sedimentary rocks prevails in high-elevation environments, while silicate weathering dominates in floodplains. This novel approach combining REE and Nd isotopes opens new perspectives for disentangling the weathering signals of sedimentary and crystalline silicate rocks in the geologic record, which could be used in future studies to reassess the causal relationships between mountain uplift, erosion and climate throughout Earth's history.
Published: 2020
Full Text: View/download PDF

13. From 'source to sink' – A new perspective on the past dynamics of the Murray Canyon Group from benthic foraminiferal communities

Author: P. De Deckker, Elisabeth Michel, M. Mojtahid, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), 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), Paléocéanographie (PALEOCEAN), 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), 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), and 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)
Subjects: 010506 paleontology, Turbidity current, 010504 meteorology & atmospheric sciences, Bathyal foraminifera, River Murray, Fluvial, Oceanography, 01 natural sciences, Bathyal zone, Abyssal zone, 14. Life underwater, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Canyon, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, geography, geography.geographical_feature_category, Last Glacial, Abyssal plain, Paleontology, Shelf foraminifera, Turbidites, Bouma-like sequence, Turbidite, Benthic zone, Abyssal foraminifera, Geology
Abstract: We present fossil benthic foraminiferal assemblage data from marine sediment core SS02/06-GC2 located in the abyssal plain of the Murray Canyon Group (offshore South Australia). The sedimentological characteristics indicate the presence of turbidite deposits showing classical Bouma-like sequences, dated between ~40 and 12 cal ka BP. These results confirm the previous interpretation of the observed large deep-water holes in the abyssal area where the core was sampled as being gouged by surges of high-energy turbidity currents. The presence of good indicator taxa and unique assemblages occupying specific bathymetric depths allows the determination of the source origin of the sediments making the turbidites. Three distinct faunal groups are found: 1) mostly shelf species, 2) mostly bathyal species and 3) mostly abyssal species. In the sediment core, these groups present a quasi-systematic succession, with nearly all Bouma-like sequences starting with the dominance of bathyal species in the coarse-grained base, followed by the dominance of shallow species in the silty part, and finally with abyssal species in the clays. To explain such phenomena, turbidites triggered by mixed hyperpycnal/hypopycnal flow processes and turbidity currents during periods of river floods are considered for the first time within the Murray Canyon Group. They are mostly related to periods of increased fluvial discharges during wet phases in the Murray-Darling Basin.
Published: 2020
Full Text: View/download PDF

14. Accessory mineral constraints on crustal evolution: elemental fingerprints for magma discrimination

Author: Oscar Laurent, Martin Guitreau, Oliver Nebel, Esa Heilimo, Mike Fowler, Emilie Bruand, Craig Storey, Clementine Antoine, Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), University of Portsmouth, Géosciences Environnement Toulouse (GET), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Météo France-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Météo France, University of Turku, Monash University [Melbourne], ANR-10-LABX-0006/10-LABX-0006,CLERVOLC,Clermont-Ferrand centre for research on volcanism(2010), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Météo France-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Météo France-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), School of Earth and Environmental Sciences [Portsmouth], Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Geotalo, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), ANR-10-LABX-0006,CLERVOLC,Clermont-Ferrand centre for research on volcanism(2010), ANR-16-IDEX-0001,CAP 20-25,CAP 20-25(2016), Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement et la société-Institut national des sciences de l'Univers (INSU - CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), ANR: 16-IDEX-0001,CAP 20-25,CAP 20-25 (I-Site)(2017), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS), and Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)
Subjects: 010504 meteorology & atmospheric sciences, Archean, Geochemistry, NERC, [SDU.STU.PE]Sciences of the Universe [physics]/Earth Sciences/Petrography, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Geochemistry and Petrology, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Titanite, [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, Environmental Chemistry, 0105 earth and related environmental sciences, Petrogenesis, [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, geography, NE/I025573/1, geography.geographical_feature_category, Mineral, Trace element, trace element, RCUK, Geology, Craton, titanite, apatite, Magma, Adakite, engineering, Earth Sciences, Archean granitoids (TTG, sanukitoid), magma evolution through time
Abstract: International audience; doi: 10.7185/geochemlet.2006 Underexplored accessory minerals such as titanite and apatite have the potential to give insights into the nature and the petrogenesis of their host rock. Their trace element and REE-rich compositions carry a record of crystallisation history and chemical characteristics of their source. Moreover, titanite and, to a certain extent, apatite are resistant to erosion during sedimentary cycles which makes them ideal to reconstruct the history of long-eroded continental land-masses. Here we report new trace element data on apatite and titanite from granitoids of different Archean cratons and comparative granitoids from the Phanerozoic. Trace element signatures of both minerals reveal systematic chemical trends in Y, LREE and Sr contents related to the nature of their host magma, which are used to construct discrimination diagrams delineating Archean TTGs from sanukitoids, and modern adakites from S/I-type granites. By comparing Archean granitoids (TTG and sanukitoids) and their Phanerozoic counterparts (adakite and high Ba-Sr granites), we show that the robust nature of these phases makes them reliable recorders of petrogenetic information from Archean rocks, that usually have been affected by secondary processes (meta-morphism, deformation, hydrothermal activity). Applied to the rock record, both phases potentially provide detailed archives of magmatic evolution through time.
Published: 2020
Full Text: View/download PDF

15. Contribution of Electroactive Humic Substances to the Iron‐Binding Ligands Released During Microbial Remineralization of Sinking Particles

Author: Philip W. Boyd, Cécile Guieu, Matthieu Bressac, Géraldine Sarthou, Hannah Whitby, Michael J. Ellwood, 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 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), Department of Earth Ocean and Ecological Sciences [Liverpool], University of Liverpool, Institute for Marine and Antarctic Studies [Horbat] (IMAS), University of Tasmania [Hobart, Australia] (UTAS), Laboratoire d'océanographie de Villefranche (LOV), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de la Mer de Villefranche (IMEV), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), New York University [Abu Dhabi], NYU System (NYU), Antarctic Climate and Ecosystems Cooperative Research Centre (ACE-CRC), ANR-10-LABX-0019,LabexMER,LabexMER Marine Excellence Research: a changing ocean(2010), European Project: 626734,EC:FP7:PEOPLE,FP7-PEOPLE-2013-IOF,IRON-IC(2014), European Project: 609102,EC:FP7:PEOPLE,FP7-PEOPLE-2013-COFUND,PRESTIGE(2014), Institut de Recherche pour le Développement (IRD)-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 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)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), University of Tasmania (UTAS), Antarctic Climate and Ecosystems Cooperative Research Centre (ACE CRC), European Union Seventh Framework Programme (FP7/2007-2013) PIOF-GA-2012-626734, EU FP7 Marie Curie actions through the PRESTIGE programmePCOFUND-GA-2013-609102, Australian Research CouncilDP170102108DP130100679FL160100131, Meteo-France as part of the programme MISTRALS, 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 Institute for Marine and Antarctic Studies [Hobart] (IMAS)
Subjects: particle, 010504 meteorology & atmospheric sciences, Iron, 010502 geochemistry & geophysics, ligand, 01 natural sciences, Marie curie, Environmental protection, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Political science, media_common.cataloged_instance, 14. Life underwater, European union, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, media_common, degradation, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, ACL, humic, remineralisation, Geophysics, 13. Climate action, Research council, General Earth and Planetary Sciences, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract: International audience; Iron is a key micronutrient in seawater, but concentrations would be negligible without the presence of organic ligands. The processes influencing the ligand pool composition are poorly constrained, limiting our understanding of the controls on dissolved iron distributions. To address this, the release of iron and iron-binding ligands during the microbial remineralization of sinking particles was investigated by deploying in situ particle interceptor/incubator devices at subsurface sites in the Mediterranean Sea and Subantarctic. Analyses revealed that the pool of released ligands was largely dominated by electroactive humic substances (74 ± 28%). The release of ligands during remineralization ensured that concurrently released iron remained in solution, which is crucial for iron regeneration. This study presents compelling evidence of the key role of humic ligands in the subsurface replenishment of dissolved iron and thus on the wider oceanic dissolved iron inventory, which ultimately controls the magnitude of iron resupplied to the euphotic zone. Plain Language Summary Microscopic plants and animals in seawater require nutrients to survive. One of these key nutrients is iron, dissolved in seawater at very low concentrations. The growth of around half of the microscopic life in the upper ocean is dependent on the availability of this dissolved iron. These organisms form the bottom of the food chain, and their growth is linked to marine productivity and the drawdown of carbon into the deep ocean, in turn influencing climate change. Because iron tends to not dissolve easily in seawater, it must bind with compounds known as ligands, which help keep iron dissolved. However, processes controlling the composition of this ligand pool are poorly understood. As material sinks through the water column, it is broken down by marine microbes, releasing iron and ligands. Here we have studied the release of iron, ligands, and a specific type of ligand known as humic substances, during the microbial degradation of sinking particles. By doing this, we have identified a large fraction of the released ligand pool. This furthers our understanding of the processes controlling dissolved iron concentrations and distributions in ocean waters, providing key information for biogeochemical modeling and for calculating carbon sequestration in seawater.
Published: 2020
Full Text: View/download PDF

16. Magnesium in subaqueous speleothems as a potential palaeotemperature proxy

Author: Ellen Corrick, Leonardo Piccini, Henri Wong, Giovanni Zanchetta, Isabelle Couchoud, Eleonora Regattieri, Aline Govin, Alan Greig, Jon Woodhead, Ilaria Isola, Trevor Ireland, John Hellstrom, Polychronis C Tzedakis, Russell N. Drysdale, Peter Holden, School of Geography [Melbourne], Faculty of Science [Melbourne], University of Melbourne-University of Melbourne, Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), University of Pisa - Università di Pisa, Istituto Nazionale di Geofisica e Vulcanologia – Sezione di Pisa (INGV), Istituto Nazionale di Geofisica e Vulcanologia, CNR Istituto di Geoscienze e Georisorse [Pisa] (IGG-CNR), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), School of Earth Sciences [Melbourne], 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), Climat et Magnétisme (CLIMAG), 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), University College of London [London] (UCL), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Australian Nuclear Science and Technology Organisation [Australie] (ANSTO), Università degli Studi di Firenze = University of Florence (UniFI), Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Consiglio Nazionale delle Ricerche (CNR), 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), Environmental Change Research Centre, Department of Geography, University College London, and Università degli Studi di Firenze, Dipartimento di Scienze della Terra (DST)
Subjects: 010504 meteorology & atmospheric sciences, Paleoclimate, Science, Cold climate, [SDE.MCG]Environmental Sciences/Global Changes, General Physics and Astronomy, Speleothem, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, 010502 geochemistry & geophysics, Palaeoclimate, 01 natural sciences, General Biochemistry, Genetics and Molecular Biology, Proxy (climate), Article, Sedimentary depositional environment, speleothem, paleotermometers, Mg/Ca, Cave, Palaeoceanography, Paleoclimatology, Magnesium Mg2+, lcsh:Science, 0105 earth and related environmental sciences, geography, Multidisciplinary, geography.geographical_feature_category, Stable isotope ratio, speleotemi, paleoclimate, speleothem, General Chemistry, Paleotemperatures, Speleothems, Geochemistry, 13. Climate action, [SDU]Sciences of the Universe [physics], [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, lcsh:Q, Physical geography, Geology
Abstract: Few palaeoclimate archives beyond the polar regions preserve continuous and datable palaeotemperature proxy time series over multiple glacial-interglacial cycles. This hampers efforts to develop a more coherent picture of global patterns of past temperatures. Here we show that Mg concentrations in a subaqueous speleothem from an Italian cave track regional sea-surface temperatures over the last 350,000 years. The Mg shows higher values during warm climate intervals and converse patterns during cold climate stages. In contrast to previous studies, this implicates temperature, not rainfall, as the principal driver of Mg variability. The depositional setting of the speleothem gives rise to Mg partition coefficients that are more temperature dependent than other calcites, enabling the effect of temperature change on Mg partitioning to greatly exceed the effects of changes in source-water Mg/Ca. Subaqueous speleothems from similar deep-cave environments should be capable of providing palaeotemperature information over multiple glacial-interglacial cycles., Few palaeoclimate archives beyond the polar regions preserve continuous and datable paleotemperature proxy time series over multiple glacial-interglacial cycles. Here, the authors show that Mg concentrations in a subaqueous speleothem from an Italian cave track regional sea-surface temperatures over the last 350,000 years.
Published: 2020
Full Text: View/download PDF

17. Upper plate deformation and trench retreat modulated by subduction-driven shallow asthenospheric flows

Author: D. Rhodri Davies, Frédéric Gueydan, Fanny Garel, Manar Alsaif, Géosciences Montpellier, Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Université des Antilles (UA)-Centre National de la Recherche Scientifique (CNRS), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), European Project: 674899,H2020,H2020-MSCA-ITN-2015,SUBITOP(2016), and Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)
Subjects: Buoyancy, 010504 meteorology & atmospheric sciences, Slab pull, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], slab rollback, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Physics::Geophysics, Physics::Fluid Dynamics, Geochemistry and Petrology, Earth and Planetary Sciences (miscellaneous), Trailing edge, Surface plate, 0105 earth and related environmental sciences, [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, Subduction, numerical modelling, trench retreat, asthenospheric mantle flow, Geophysics, Shear (geology), Space and Planetary Science, Trench, Slab, engineering, subduction, Seismology, Geology, upper plate deformation
Abstract: International audience; Upper plate deformation within a subduction zone depends on the complex relationship between surface plate motions, trench motion, slab pull and asthenospheric flow. Previous modelling studies suggest that trench motion rates should be related to slab buoyancy, but this relationship is neither clear nor verified by observations of natural subduction systems. Trench motion is also thought to induce upper plate deformation; however, no clear correlation has been identified between the direction of trench motion and the mode of upper plate deformation. In this study, we construct 2-D thermo-mechanical models to explore the relationship between slab pull, trench retreat and upper plate deformation, focusing on subduction systems with retreating trenches. We start with quasi-steady-state subduction and introduce a positive density anomaly into the slab to transiently increase slab pull. We vary both the value of the density anomaly and the properties of the upper plate to isolate key controls on trench retreat and upper plate deformation. Our models indicate that asthenospheric flow responds to changes in slab pull and influences both trench retreat and upper plate deformation. We propose that trench retreat depends on the competition between shallow and opposite asthenospheric flows below the subducting and upper plates, and that a fast sub-slab flow can hamper trench retreat even when slab buoyancy is high. After a transient slab pull increase, the mode of upper plate deformation partly depends on the upper plate's ability to translate horizontally: an upper plate with a ridge at its trailing edge deforms by shortening, while a fixed upper plate may deform by extension. Finally, in some cases, upper plate deformation seems to allow trench retreat if the upper plate is weak enough to be deformed by the basal shear from underlying asthenospheric flow. Our results provide insights into retreating subduction systems with contrasting upper plate deformation modes, such as the compressive Andes and the extensional Aegean.
Published: 2020
Full Text: View/download PDF

18. Phase relations and melting of nominally ‘dry’ residual eclogites with variable CaO/Na2O from 3 to 5 GPa and 1250 to 1500 °C; implications for refertilisation of upwelling heterogeneous mantle

Author: Carl Spandler, Wilson A. Crichton, Judit K. Sándorné, Estelle Rose-Koga, Anne-Aziliz Pelleter, István Kovács, Anja Rosenthal, Gregory M. Yaxley, Joerg Hermann, Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), European Synchrotron Radiation Facility (ESRF), Geological and Geophysical Institute of Hungary, ANR-10-LABX-0006,CLERVOLC,Clermont-Ferrand centre for research on volcanism(2010), ANR-16-IDEX-0001,CAP 20-25,CAP 20-25(2016), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)
Subjects: Experimental petrology, 010504 meteorology & atmospheric sciences, Geochemistry, Pyroxene, Solidus, Phase relations, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Mantle (geology), [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Geochemistry and Petrology, Coesite, Petrology, 0105 earth and related environmental sciences, Peridotite, Grossular, Andesite, Geology, magmas, Residual eclogites, 13. Climate action, Heterogeneous mantle melting, visual_art, visual_art.visual_art_medium, engineering, Petrogenesis of primitive mantle-derived, Eclogite
Abstract: This study investigates the phase and melting relations of nominally ‘dry’ residual eclogites (Res2 and Res3), with varying bulk CaO/Na2O ratios (4 and 12, respectively), from ~160 (5 GPa) to ~90 km (3 GPa) depth. Garnet, clinopyroxene and minor quartz/coesite are subsolidus phases in both compositions. In contrast to Res2, in Res3, the proportions of garnet always exceeding those of clinopyroxene. This also leads to higher modal quartz/coesite in Res3 relative to Res2. In modelling melting along a near-adiabatic upwelling path with a mantle potential temperature of ~1360 °C, at 5 GPa, near-solidus andesitic Res3 partial melts are much less siliceous and sodic, and are more calcic and magnesian than the incipient dacitic melts of Res2. Continuously self-fluxed melting increases considerably from 4 to 3 GPa due to the increased breakdown of Ca-Eskolaite solid solution component in clinopyroxene along the adiabat. This causes a steepening of the solidus, but more-so for Res2 than for Res3. At 3 GPa, the near exhaustion of residual clinopyroxene causes higher melt productivity for Res3 (~60%) than for Res2 (~30%), despite both melts being of basaltic-andesite composition. Resulting Res3 melts are therefore significantly more calcic and magnesian, and less sodic than those of Res2 melts. As Res3 undergoes a higher degree of melting relative to Res2 during adiabatic ascent, Res3 eclogitic residues become significantly more refractory; with relatively higher Mg# and grossular in garnet, higher Mg# and Ca-tschermaks, and lower jadeite components of clinopyroxene, and higher garnet/clinopyroxene ratios than eclogitic Res2 residuals. In upwelling heterogenous mantle domains, the siliceous eclogitic melts formed within a body of eclogite will react with encapsulating mantle peridotite, effectively refertilising it and producing hybrid pyroxene- and garnet-rich rocks. Subsequent melting of these sources may lead to compositionaly diverse primitive mantle-derived magmas, with high Ca/Al and low Na/Ca signatures indicators of preferential melting of a heterogeneous mantle, previously refertilised by recycled Ca-rich oceanic crustal material, and primitive magmas with low Ca/Al and high Na/Ca derived from melting of mantle with a ‘normal recycled crustal material signature’. Thus, compositional magma diversity may directly reflect precursor compositions of the mantle source region.
Published: 2018
Full Text: View/download PDF

19. Arsenic Speciation in Mekong Delta Sediments Depends on Their Depositional Environment

Author: Maria P. Asta, Manon Frutschi, Pierre Le Pape, Frédéric Herman, Laurent Charlet, Rizlan Bernier-Latmani, Yuheng Wang, Barbora Bártová, Vu Hoai Cong Pham, Georgina E. King, Maya Ikogou, Phu Le Vo, Elena I. Suvorova, Guillaume Morin, Institut de minéralogie et de physique des milieux condensés (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Ecole Polytechnique Fédérale de Lausanne (EPFL), University of Bern, Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC), Ho Chi Minh City University of Technology (HCMUT), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Laboratoire de Géophysique Interne et Tectonophysique (LGIT), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Laboratoire Central des Ponts et Chaussées (LCPC)-Institut des Sciences de la Terre (ISTerre), 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)-Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Institute of Earth Sciences, Université de Lausanne (UNIL), Institut des Sciences de la Terre (ISTerre), 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])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), and Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS)
Subjects: inorganic chemicals, Geologic Sediments, Geochemistry, chemistry.chemical_element, Aquifer, 010501 environmental sciences, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Arsenic, Sedimentary depositional environment, Environmental Chemistry, Organic matter, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Groundwater, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, chemistry.chemical_classification, geography, geography.geographical_feature_category, Sediment, General Chemistry, 6. Clean water, Arsenic contamination of groundwater, Vietnam, chemistry, [SDU]Sciences of the Universe [physics], 13. Climate action, [SDE]Environmental Sciences, engineering, Environmental science, Alluvium, Pyrite, Water Pollutants, Chemical, Environmental Monitoring
Abstract: Arsenic contamination in groundwater is pervasive throughout deltaic regions of Southeast Asia and threatens the health of millions. The speciation of As in sediments overlying contaminated aquifers is poorly constrained. Here, we investigate the chemical and mineralogical compositions of sediment cores collected from the Mekong Delta in Vietnam, elucidate the speciation of iron and arsenic, and relate them to the sediment depositional environment. Gradual dissolution of ferric (oxyhydr)oxides with depth is observed down to 7 m, corresponding to the establishment of reducing conditions. Within the reduced sediment, layers originating from marine, coastal or alluvial depositional environments are identified and their age is consistent with a late Holocene transgression in the Mekong Delta. In the organic matter- and sulfur-rich layers, arsenic is present in association with organic matter through thiol-bonding and in the form of arsenian pyrite. The highest arsenic concentration (34-69 ppm) is found in the peat layer at 16 m and suggests the accumulation of arsenic due to the formation of thiol-bound trivalent arsenic (40-55%) and arsenian pyrite (15-30%) in a paleo-mangrove depositional environment (∼8079 yr BP). Where sulfur is limited, siderite is identified, and oxygen- and thiol-bound trivalent arsenic are the predominant forms. It is also worth noting that pentavalent arsenic coordinated to oxygen is ubiquitous in the sediment profile, even in reduced sediment layers. But the identity of the oxygen-bound arsenic species remains unknown. This work shows direct evidence of thiol-bound trivalent arsenic in the Mekong Delta sediments and provides insight to refine the current model of the origin, deposition, and release of arsenic in the alluvial aquifers of the Mekong Delta.
Published: 2018
Full Text: View/download PDF

20. Numerical approximation of the 3d hydrostatic Navier-Stokes system with free surface

Author: Sebastien Allgeyer, Anne Mangeney, Raouf Hamouda, Marie-Odile Bristeau, Jacques Sainte-Marie, David Froger, Fabien Souillé, Martin Vallée, Vincent Jauzein, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Numerical Analysis, Geophysics and Ecology (ANGE), Inria de Paris, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire Jacques-Louis Lions (LJLL (UMR_7598)), Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Sorbonne Université (SU), SAUR, Institut de Physique du Globe de Paris (IPGP), 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), This work has been partially funded by the ERC Contract No. ERC-CG-2013-PE10-617472 SLIDEQUAKES.The authors also acknowledge the Inria Project Lab 'Algae in Silico' for its financial support, 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), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Free surface flows, Free surface, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Kinetic interpretation, Basis function, 010103 numerical & computational mathematics, Hydrostatic assumption, 01 natural sciences, Kinetic description, FOS: Mathematics, Numerical simulations, Applied mathematics, [MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP], Mathematics - Numerical Analysis, 0101 mathematics, Navier–Stokes equations, Galerkin method, Mathematics, Numerical Analysis, Conservation law, Finite volume method, Finite volumes, Applied Mathematics, 3d model, Numerical Analysis (math.NA), Euler system, 010101 applied mathematics, Computational Mathematics, Finite volume scheme, Modeling and Simulation, Piecewise, Navier-Stokes equations, Analysis, [MATH.MATH-NA]Mathematics [math]/Numerical Analysis [math.NA]
Abstract: In this paper we propose a stable and robust strategy to approximate the 3D incompressible hydrostatic Euler and Navier–Stokes systems with free surface. Compared to shallow water approximation of the Navier–Stokes system, the idea is to use a Galerkin type approximation of the velocity field with piecewise constant basis functions in order to obtain an accurate description of the vertical profile of the horizontal velocity. Such a strategy has several advantages. It allowsto rewrite the Navier–Stokes equations under the form of a system of conservation laws with source terms,the easy handling of the free surface, which does not require moving meshes,the possibility to take advantage of robust and accurate numerical techniques developed in extensive amount for Shallow Water type systems.Compared to previous works of some of the authors, the three dimensional case is studied in this paper. We show that the model admits a kinetic interpretation including the vertical exchanges terms, and we use this result to formulate a robust finite volume scheme for its numerical approximation. All the aspects of the discrete scheme (fluxes, boundary conditions, ...) are completely described and the stability properties of the proposed numerical scheme (well-balancing, positivity of the water depth, ...) are discussed. We validate the model and the discrete scheme with some numerical academic examples (3D non stationary analytical solutions) and illustrate the capability of the discrete model to reproduce realistic tsunami waves propagation, tsunami runup and complex 3D hydrodynamics in a raceway.
Published: 2019
Full Text: View/download PDF

21. Very- and ultra-long-period seismic signals prior to and during caldera formation on La Réunion Island

Author: Valérie Ferrazzini, Geneviève Roult, Fabrice R. Fontaine, Dominique Reymond, Babak Hejrani, Hrvoje Tkalčić, A. Di Muro, Aline Peltier, Guilhem Barruol, Frédérick Massin, Laurent Michon, Thomas Staudacher, Laboratoire GéoSciences Réunion (LGSR), Université de La Réunion (UR)-Institut de Physique du Globe de Paris, Institut de Physique du Globe de Paris (IPGP), 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), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Observatoire Volcanologique du Piton de la Fournaise (OVPF), Institut de Physique du Globe de Paris, Laboratoire de Détection et de Géophysique (CEA) (LDG), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Swiss Seismological Service [ETH Zurich] (SED), Institute of Geophysics [ETH Zürich], Department of Earth Sciences [Swiss Federal Institute of Technology - ETH Zürich] (D-ERDW), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)-Department of Earth Sciences [Swiss Federal Institute of Technology - ETH Zürich] (D-ERDW), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Department of Earth Sciences [ETH Zürich] (D-ERDW), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Department of Earth Sciences [ETH Zürich] (D-ERDW), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), and Institut de Physique du Globe de Paris (IPG Paris)
Subjects: 0301 basic medicine, Seismometer, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Population, Volcanology, lcsh:Medicine, Induced seismicity, Fault (geology), Article, 03 medical and health sciences, 0302 clinical medicine, [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, Caldera, 14. Life underwater, education, lcsh:Science, Seismology, geography, education.field_of_study, Multidisciplinary, geography.geographical_feature_category, Explosive eruption, lcsh:R, Natural hazards, 030104 developmental biology, Volcano, Magma, lcsh:Q, 030217 neurology & neurosurgery, Geology
Abstract: International audience; early detection of the onset of a caldera collapse can provide crucial information to understand their formation and thus to minimize risks for the nearby population and visitors. Here, we analyse the 2007 caldera collapse of piton de la Fournaise on La Réunion Island recorded by a broadband seismic station. We show that this instrument recorded ultra-long period (ULP) signals with frequencies in the range (0.003-0.01 Hz) accompanied by very-long period (VLP) signals (between 0.02 and 0.50 Hz) prior to and during the caldera formation suggesting it is possible to detect the beginning of the collapse at depth and anticipate its surface formation. Interestingly, VLP wave packets with a similar duration of 20 s are identified prior to and during the caldera formation. We propose that these events could result from repeating piston-like successive collapses occurring through a ring-fault structure surrounding a magma reservoir from the following arguments: the source mechanism from the main collapse, the observations of slow source processes as well as observations from the field and the characteristic ring-fault seismicity. Caldera collapses are rare (only seven events over the last 100 years) and particularly destructive volcanic events that can induce catastrophic changes in the shape of a volcanic edifice and its environment 1. Identifying the occurrence of the first collapse at depth is of major importance in evaluating the triggering factors and anticipating the caldera surface formation. This detection can help to predict or at least indicate early future caldera collapses and subsequent consequences such as explosive eruptions, (e.g. those that followed the major Kīlauea Caldera collapse in 1470-1510 2), or atmospheric impacts 3. In the past two decades only four caldera collapses have been monitored by dense geophysical networks: chronologically, the 2000 Miyake-jima, Japan; the 2007 Piton de la Fournaise, La Réunion/France; the 2014-2015 Bárðarbunga, Iceland; and the 2018 Kīlauea, Hawai'i 4-7. Laboratory experiments and numerical analyses predicted the occurrence of precursory collapses at depth before the onset of the surface subsidence 8-12 but observations obtained from adequate broadband seismometers were lacking. Until the present study, the Miyake-jima caldera formation was the only known case with evidence of such deep collapses before the faults reached the surface. The deep collapses were suggested from observations of VLP seismic pulses of 20 s width 13. However, the timing of the first collapse at depth was not reported. VLP signals observed at volcanoes are generally considered having frequencies between 0.01-0.5 Hz (ref. 14) and until the 2000 Miyake-jima event, they were generally considered to result from inertial forces associated with changes in the flow of magma and gases through conduits 14. The VLP signals detected during the Miyake-jima caldera formation were explained by different physical mechanisms: (i) a buried geyser model 15 , (ii) a piston-like model 4,13,16 , and (iii) ring-faulting mechanisms related to shear failure on curved or cone-shaped fault structures 17,18. 46 step-like tilt changes (TC) were observed during the Miyake-jima caldera formation and among them 39 were accompanied by the VLP seismic signals 4,19,20. The origin of these TC associated with the VLP pulses have been attributed to either a piston model with a vertical rock column intermittently sinking into a magma reservoir 4,21 or to a magma sheet model with a large sill-like
Published: 2019
Full Text: View/download PDF

22. A new species of Homo from the Late Pleistocene of the Philippines

Author: Philip Piper, Rainer Grün, Guillaume Daver, Eusebio Z. Dizon, Armand Salvador B. Mijares, Julien Corny, Clément Zanolli, Florent Détroit, Emil Charles Robles, Histoire naturelle de l'Homme préhistorique (HNHP), Muséum national d'Histoire naturelle (MNHN)-Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS), University of the Philippines (UP System), Laboratoire de paléontologie, évolution, paléoécosystèmes, paléoprimatologie (PALEVOPRIM ), Université de Poitiers-Centre National de la Recherche Scientifique (CNRS), De la Préhistoire à l'Actuel : Culture, Environnement et Anthropologie (PACEA), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), Anthropologie Moléculaire et Imagerie de Synthèse (AMIS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), National Museum of the Philippines, Griffith University [Brisbane], Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), School of Archaeology & Anthropology, Dipartimento di Studi Umanistici, Ita, Università degli Studi di Ferrara (UniFE), Dynamique de l'évolution humaine : individus, populations, espèces [Paris] (DEHIPE), Centre National de la Recherche Scientifique (CNRS), Research School of Earth Sciences and Research School of Pacific and Asian Studies, Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Université de Perpignan Via Domitia (UPVD), and University of the Philippines
Subjects: Primates, 010506 paleontology, Pleistocene, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, Biological anthropology, [SHS.ANTHRO-BIO]Humanities and Social Sciences/Biological anthropology, Wallace Line, 01 natural sciences, Southeast asia, Cave, Genus, Animalia, 0601 history and archaeology, Chordata, 0105 earth and related environmental sciences, Taxonomy, geography, 060101 anthropology, Multidisciplinary, geography.geographical_feature_category, biology, Palaeontology, Hominidae, 06 humanities and the arts, Biodiversity, biology.organism_classification, Palaeontology, Archaeology, Biological anthropology, Homo floresiensis, Archaeology, Evolutionary biology, Homo sapiens, Mammalia, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology
Abstract: International audience; A hominin third metatarsal discovered in 2007 in Callao Cave (Northern Luzon, the Philippines) and dated to 67 thousand years ago provided the earliest direct evidence of a human presence in the Philippines. Analysis of this foot bone suggested that it belonged to the genus Homo, but to which species was unclear. Here we report the discovery of twelve additional hominin elements that represent at least three individuals that were found in the same stratigraphic layer of Callao Cave as the previously discovered metatarsal. These specimens display a combination of primitive and derived morphological features that is different from the combination of features found in other species in the genus Homo (including Homo floresiensis and Homo sapiens) and warrants their attribution to a new species, which we name Homo luzonensis. The presence of another and previously unknown hominin species east of the Wallace Line during the Late Pleistocene epoch underscores the importance of island Southeast Asia in the evolution of the genus Homo.
Published: 2019
Full Text: View/download PDF

23. Investigating the seismic and geological structure of the martian crust at the dichotomy boundary

Author: Tauzin, Benoit, Pan, Lu, Michaut, Chloé, Quantin-Nataf, Cathy, Schmerr, Nick, Perrin, Clément, Lognonné, Phillipe, Ansan, Veronique, 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), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Department of Geology [College Park], University of Maryland [College Park], University of Maryland System-University of Maryland System, 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), Université Pierre et Marie Curie - Paris 6 (UPMC)-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 Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), European Project: MSCA No. 793824,NoLiMit, 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 national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), 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)-Université de La Réunion (UR)-Université Paris Diderot - Paris 7 (UPD7)-IPG PARIS-Institut national des sciences de l'Univers (INSU - CNRS), and Laboratoire de Planétologie et de Géodynamique, Université de Nantes
Subjects: [SDU.STU.PL]Sciences of the Universe [physics]/Earth Sciences/Planetology, [SDU]Sciences of the Universe [physics], [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2019

24. Southern Europe climate oscillations at marine isotope stage 5a

Author: Chung, Yun-Chuan, Hu, Hsun-Ming, Mii, Horng-Sheng, Michel, Véronique, Valensi, Patricia, Jiang, Xiuyang, Shen, Chuan-Chou, Grant, Katharine, High-Precision Mass Spectrometry and Environment Change Laboratory (HISPEC), National Taiwan University [Taiwan] (NTU), Culture et Environnements, Préhistoire, Antiquité, Moyen-Age (CEPAM), Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), Géoazur (GEOAZUR 7329), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Histoire naturelle de l'Homme préhistorique (HNHP), Muséum national d'Histoire naturelle (MNHN)-Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Ocean and Earth Science [Southampton], and University of Southampton-National Oceanography Centre (NOC)
Subjects: Europe, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, [SDU]Sciences of the Universe [physics], oscillations, marine, isotope, stage, climate, Southern, ComputingMilieux_MISCELLANEOUS, [SHS]Humanities and Social Sciences
Abstract: Southern Europe climate oscillations at marine isotope stage 5a
Published: 2019

25. Investigating marine bio‐calcification mechanisms in a changing ocean with in vivo and high‐resolution ex vivo Raman spectroscopy

Author: Malcolm T. McCulloch, Paul Guagliardo, Christopher E. Cornwall, Aleksey Sadekov, Thomas M. DeCarlo, Steeve Comeau, Julie Trotter, Emma Thillainath, Laura Gajdzik, The University of Western Australia (UWA), Laboratoire de Morphologie Fonctionnelle et Evolutive, Université de Liège, University of Cambridge [UK] (CAM), Research School of Earth Sciences [Canberra] (RSES), and Australian National University (ANU)
Subjects: 0106 biological sciences, Aquatic Organisms, 010504 meteorology & atmospheric sciences, [SDE.MCG]Environmental Sciences/Global Changes, Carbonates, High resolution, ocean acidification, Spectrum Analysis, Raman, 010603 evolutionary biology, 01 natural sciences, Foraminifera, calcification, symbols.namesake, Calcification, Physiologic, In vivo, medicine, Environmental Chemistry, Animals, Seawater, 14. Life underwater, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, General Environmental Science, Global and Planetary Change, Ecology, biology, foraminifera, Coralline algae, Ocean acidification, Hydrogen-Ion Concentration, biology.organism_classification, medicine.disease, in vivo, Oceanography, otoliths, Technical Advance, corals, 13. Climate action, Raman spectroscopy, [SDE]Environmental Sciences, symbols, Environmental science, coralline algae, Ex vivo, Water Pollutants, Chemical, Calcification
Abstract: Ocean acidification poses a serious threat to marine calcifying organisms, yet experimental and field studies have found highly diverse responses among species and environments. Our understanding of the underlying drivers of differential responses to ocean acidification is currently limited by difficulties in directly observing and quantifying the mechanisms of bio‐calcification. Here, we present Raman spectroscopy techniques for characterizing the skeletal mineralogy and calcifying fluid chemistry of marine calcifying organisms such as corals, coralline algae, foraminifera, and fish (carbonate otoliths). First, our in vivo Raman technique is the ideal tool for investigating non‐classical mineralization pathways. This includes calcification by amorphous particle attachment, which has recently been controversially suggested as a mechanism by which corals resist the negative effects of ocean acidification. Second, high‐resolution ex vivo Raman mapping reveals complex banding structures in the mineralogy of marine calcifiers, and provides a tool to quantify calcification responses to environmental variability on various timescales from days to years. We describe the new insights into marine bio‐calcification that our techniques have already uncovered, and we consider the wide range of questions regarding calcifier responses to global change that can now be proposed and addressed with these new Raman spectroscopy tools., Newly developed in vivo and high‐resolution Raman spectroscopy analyses of marine calcifying organisms enable characterization of their mineralogy and calcification mechanisms. Insights from these new Raman spectroscopy tools are helping us understand the sensitivity of these important organisms to ocean warming and acidification.
Published: 2019
Full Text: View/download PDF

26. Multi-trace-element sea surface temperature coral reconstruction for the southern Mozambique Channel reveals teleconnections with the tropical Atlantic

Author: J. Zinke, J. P. D'Olivo, C. J. Gey, M. T. McCulloch, J. H. Bruggemann, J. M. Lough, M. M. M. Guillaume, Australian Institute of Marine Science (AIMS), The ARC Centre of Excellence for Coral Reefs Studies [Townsville, Australie] (ARC), Freie Universität Berlin, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Ecologie marine tropicale dans les Océans Pacifique et Indien (ENTROPIE [Réunion]), Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Institut de Recherche pour le Développement (IRD), Laboratoire d'Excellence CORAIL (LabEX CORAIL), Institut de Recherche pour le Développement (IRD)-Université des Antilles et de la Guyane (UAG)-École des hautes études en sciences sociales (EHESS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de La Réunion (UR)-Université de la Polynésie Française (UPF)-Université de la Nouvelle-Calédonie (UNC)-Institut d'écologie et environnement-Université des Antilles (UA), Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU), Université des Antilles (UA)-Institut d'écologie et environnement-Université de la Nouvelle-Calédonie (UNC)-Université de la Polynésie Française (UPF)-Université de La Réunion (UR)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École des hautes études en sciences sociales (EHESS)-Université des Antilles et de la Guyane (UAG)-Institut de Recherche pour le Développement (IRD), Institut de Recherche pour le Développement (IRD)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Université des Antilles et de la Guyane (UAG)-École des hautes études en sciences sociales (EHESS)-École Pratique des Hautes Études (EPHE), Université de Caen Normandie (UNICAEN), and Normandie Université (NU)-Normandie Université (NU)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)
Subjects: 010504 meteorology & atmospheric sciences, tropical Atlantic, coral reconstruction, Porites, lcsh:Life, southern Mozambique Channel, Subtropics, Tropical Atlantic, 010502 geochemistry & geophysics, 01 natural sciences, lcsh:QH540-549.5, 14. Life underwater, Reef, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, Earth-Surface Processes, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, geography, geography.geographical_feature_category, biology, lcsh:QE1-996.5, Europa Island, biology.organism_classification, lcsh:Geology, lcsh:QH501-531, Sea surface temperature, La Niña, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, 13. Climate action, Climatology, lcsh:Ecology, Geology, Teleconnection
Abstract: Here we report seasonally resolved sea surface temperatures for the southern Mozambique Channel in the SW Indian Ocean based on multi-trace-element temperature proxy records preserved in two Porites sp. coral cores. Particularly, we assess the suitability of both separate and combined Sr∕Ca and Li∕Mg proxies for improved multielement SST reconstructions. Overall, geochemical records from Europa Island Porites sp. highlight the potential of Sr∕Ca and Li∕Mg ratios as high-resolution climate proxies but also show significant differences in their response at this Indian Ocean subtropical reef site. Our reconstruction from 1970 to 2013 using the Sr∕Ca SST proxy reveals a warming trend of 0.58±0.1 ∘C in close agreement with instrumental data (0.47±0.07 ∘C) over the last 42 years (1970–2013). In contrast, the Li∕Mg showed unrealistically large warming trends, most probably caused by uncertainties around different uptake mechanisms of the trace elements Li and Mg and uncertainties in their temperature calibration. In our study, Sr∕Ca is superior to Li∕Mg to quantify absolute SST and relative changes in SST. However, spatial correlations between the combined detrended Sr∕Ca and Li∕Mg proxies compared to instrumental SST at Europa revealed robust correlations with local climate variability in the Mozambique Channel and teleconnections to regions in the Indian Ocean and southeastern Pacific where surface wind variability appeared to dominate the underlying pattern of SST variability. The strongest correlation was found between our Europa SST reconstruction and instrumental SST records from the northern tropical Atlantic. Only a weak correlation was found with ENSO, with recent warm anomalies in the geochemical proxies coinciding with strong El Niño or La Niña. We identified the Pacific–North American (PNA) atmospheric pattern, which develops in the Pacific in response to ENSO, and the tropical North Atlantic SST as the most likely causes of the observed teleconnections with the Mozambique Channel SST at Europa.
Published: 2019
Full Text: View/download PDF

27. SEASTAR : a mission to study ocean submesoscale dynamics and small-scale atmosphere-ocean processes in coastal, shelf and polar seas

Author: Gommenginger, Christine, Chapron, Bertrand, Hogg, Andy, Buckingham, Christian, Fox-Kemper, Baylor, Eriksson, Leif, Soulat, Francois, Ubelmann, Clement, Ocampo-Torres, Francisco, Nardelli, Bruno Buongiorno, Griffin, David, Lopez-Dekker, Paco, Knudsen, Per, Andersen, Ole, Stenseng, Lars, Stapleton, Neil, Perrie, William, Violante-Carvalho, Nelson, Schulz-Stellenfleth, Johannes, Woolf, Isern-Fontanet, Jordi, Ardhuin, Fabrice, Klein, Patrice, Mouche, Alexis, Pascual, Ananda, Capet, Xavier, Hauser, Daniele, Stoffelen, Morrow, Rosemary, Aouf, Lotfi, Breivik, Oyvind, Lee-Lueng, Johannessen, Johnny A., Aksenov, Yevgeny, Bricheno, Lucy, Hirschi, Joel, Martin, Adrien C. H., Adrian P., Nurser, George, Polton, Jeff, Wolf, Judith, Johnsens, Harald, Soloviev, Alexander, Jacobs, Gregg A., Collard, Groom, Steve, Kudryavtsev, Vladimir, Wilkin, John, Navarro, Victor, Babanin, Alex, Matthew, Siddorn, Saulter, Andrew, Rippeth, Tom, Emery, Bill, Maximenko, Nikolai, Romeiser, Roland, Graber, Hans, Azcarate, Aida Alvera, Hughes, Chris W., Vandemark, Doug, da Silva, Jose, Van Leeuwen, Peter Jan, Naveira-Garabato, Alberto, Gemmrich, Mahadevan, Amala, Marquez, Munro, Yvonne, Doody, Sam, Burbidge, Geoff, National Oceanography Centre [Southampton] (NOC), University of Southampton, Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), 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), Department of Earth, Environmental and Planetary Sciences [Providence], Brown University, Collecte Localisation Satellites (CLS), Centro de Investigacion Científica y de Educacion Superior de Ensenada, Consiglio Nazionale delle Ricerche [Bologna] (CNR), Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Department of Geoscience and Remote Sensing [Delft], Delft University of Technology (TU Delft), National Space Institute [Lyngby] (DTU Space), Danmarks Tekniske Universitet = Technical University of Denmark (DTU), Department of Planning [Aalborg], Aalborg University [Denmark] (AAU), Defence Science and Technology Laboratory (Dstl), Ministry of Defence (UK) (MOD), Institut océanographique Bedford - Bedford Oceanographic Institute [Dartmouth, Canada] (IOB), Department or Ocean Engineering [Rio de Janeiro], Universidade Federal do Rio de Janeiro (UFRJ), Institut für Küstenforschung / Institute of Coastal Research, Helmholtz-Zentrum Geesthacht (GKSS), School of Energy, Geoscience, Infrastruture and Society (EGIS), Heriot-Watt University [Edinburgh] (HWU), Institute of Marine Sciences / Institut de Ciències del Mar [Barcelona] (ICM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Institut Mediterrani d'Estudis Avancats (IMEDEA), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad de las Islas Baleares (UIB), Processus et interactions de fine échelle océanique (PROTEO), 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)-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), SPACE - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-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)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Royal Netherlands Meteorological Institute (KNMI), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Météo-France Direction Interrégionale Sud-Est (DIRSE), Météo-France, Norwegian Meteorological Institute [Oslo] (MET), Geophysical Institute [Bergen] (GFI / BiU), University of Bergen (UiB), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Nansen Environmental and Remote Sensing Center [Bergen] (NERSC), National Oceanography Centre (NOC), National Oceanographic Centre [Liverpool] (NOC ), Northern Research Institute Tromsø (NORUT), Halmos College of Natural Sciences and Oceanography, Nova Southeastern University (NSU), Naval Research Laboratory (NRL), OceanDataLab, Plymouth Marine Laboratory (PML), Satellite Oceanography Laboratory [St Petersburg] (SOLab), Russian State Hydrometeorological University [St.Petersburg] (RSHU), Department of Marine and Coastal Sciences [New Brunswick], School of Environmental and Biological Sciences [New Brunswick], Rutgers, The State University of New Jersey [New Brunswick] (RU), Rutgers University System (Rutgers)-Rutgers University System (Rutgers)-Rutgers, The State University of New Jersey [New Brunswick] (RU), Rutgers University System (Rutgers)-Rutgers University System (Rutgers), Starlab SLU [Barcelona, Spain], Department of Infrastructure Engineering [Melbourne], Melbourne School of Engineering [Melbourne], University of Melbourne-University of Melbourne, Met Office Hadley Centre for Climate Change (MOHC), United Kingdom Met Office [Exeter], School of Ocean Sciences [Menai Bridge], Bangor University, Colorado Center for Astrodynamics Research (CCAR), University of Colorado [Boulder], School of Ocean and Earth Science and Technology (SOEST), University of Hawai‘i [Mānoa] (UHM), Rosenstiel School of Marine and Atmospheric Science (RSMAS), University of Miami [Coral Gables], GeoHydrodynamics and Environment Research (GHER), Université de Liège, Department of Earth Ocean and Ecological Sciences [Liverpool], University of Liverpool, College of Engineering and Physical Dciences [UNH Durham] (CEPS), University of New Hampshire (UNH), Departamento de Geociencias, Ambiente e Ordenamento do Territorio (DGAOT), Universidade do Porto = University of Porto, Department of Meteorology [Reading], University of Reading (UOR), Department of Atmospheric Science [Fort Collins], Colorado State University [Fort Collins] (CSU), Ocean and Earth Science [Southampton], University of Southampton-National Oceanography Centre (NOC), Department of Physics and Astronomy [Victoria], University of Victoria [Canada] (UVIC), Woods Hole Oceanographic Institution (WHOI), Airbus Defence and Space Ltd [Portsmouth], Centre for Earth Observation Instrumentation (UK), European Commission, Institut Français de Recherche pour l'Exploitation de la Mer - Brest (IFREMER Centre de Bretagne), Technical University of Denmark [Lyngby] (DTU), 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), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Météo France, Plymouth Marine Laboratory, and Universidade do Porto
Subjects: 0106 biological sciences, air sea interactions, lcsh:QH1-199.5, 010504 meteorology & atmospheric sciences, Mixed layer, Marginal Ice Zone (MIZ), Oceanography, 01 natural sciences, Remote Sensing, Wind wave, SDG 13 - Climate Action, Cryosphere, lcsh:Science, Submesocale, Physics::Atmospheric and Oceanic Physics, SDG 15 - Life on Land, Water Science and Technology, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Global and Planetary Change, geography.geographical_feature_category, marginal ice zone, dynamics, Ocean color, Climatology, coastal marginal ice zone, satellite, Air-sea interactions, coastal, Ocean Engineering, submesoscale, lcsh:General. Including nature conservation, geographical distribution, Aquatic Science, Physics::Geophysics, along-track interferometry, SDG 14 - Life Below Water, 14. Life underwater, 0105 earth and related environmental sciences, geography, Continental shelf, 010604 marine biology & hydrobiology, Ocean current, Along-track (AT) interferometry, Sea surface temperature, upper ocean dynamics, 13. Climate action, Polar seas, lcsh:Q, radar
Abstract: 7 pages, 2 figures, High-resolution satellite images of ocean color and sea surface temperature reveal an abundance of ocean fronts, vortices and filaments at scales below 10 km but measurements of ocean surface dynamics at these scales are rare. There is increasing recognition of the role played by small scale ocean processes in ocean-atmosphere coupling, upper-ocean mixing and ocean vertical transports, with advanced numerical models and in situ observations highlighting fundamental changes in dynamics when scales reach 1 km. Numerous scientific publications highlight the global impact of small oceanic scales on marine ecosystems, operational forecasts and long-term climate projections through strong ageostrophic circulations, large vertical ocean velocities and mixed layer re-stratification. Small-scale processes particularly dominate in coastal, shelf and polar seas where they mediate important exchanges between land, ocean, atmosphere and the cryosphere, e.g., freshwater, pollutants. As numerical models continue to evolve toward finer spatial resolution and increasingly complex coupled atmosphere-wave-ice-ocean systems, modern observing capability lags behind, unable to deliver the high-resolution synoptic measurements of total currents, wind vectors and waves needed to advance understanding, develop better parameterizations and improve model validations, forecasts and projections. SEASTAR is a satellite mission concept that proposes to directly address this critical observational gap with synoptic two-dimensional imaging of total ocean surface current vectors and wind vectors at 1 km resolution and coincident directional wave spectra. Based on major recent advances in squinted along-track Synthetic Aperture Radar interferometry, SEASTAR is an innovative, mature concept with unique demonstrated capabilities, seeking to proceed toward spaceborne implementation within Europe and beyond, CG and AM received funding from the United Kingdom Centre for Earth Observation Instrumentation SEASTAR+ project (Contract No. RP10G0435A02). PVL was supported by the European Research Council (ERC) CUNDA project 694509 under the European Union Horizon 2020 Research and Innovation Program
Published: 2019
Full Text: View/download PDF

28. Trans-Dimensional Surface Reconstruction With Different Classes of Parameterization

Author: Malcolm Sambridge, Thomas Bodin, Rhys Hawkins, Laurent Husson, Gaël Choblet, 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), 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), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre (ISTerre), and 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])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: Government, 010504 meteorology & atmospheric sciences, Horizon (archaeology), Operations research, business.industry, uncertainty quantification, Software development, 010502 geochemistry & geophysics, 01 natural sciences, Geophysics, Geochemistry and Petrology, Bayesian surface reconstruction, [SDU]Sciences of the Universe [physics], Bayesian surface reconstruction, trans-dimensional, uncertainty quantification, Uncertainty quantification, trans-dimensional, business, Geology, Surface reconstruction, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: International audience; The use of Bayesian trans-dimensional sampling in 2-D and 3-D imaging problems has recently become widespread in geophysical inversion. Its benefits include its spatial adaptability to the level of information present in the data and the ability to produce uncertainty estimates. The most used parameterization in Bayesian trans-dimensional inversions is Voronoi cells. Here we introduce a general software, TransTessellate2D, that allows 2-D trans-dimensional inference with Voronoi cells and two alternative underlying parameterizations, Delaunay triangulation with linear interpolation and Clough-Tocher interpolation, which utilize the same algorithm but result in either C 0 or C 1 continuity. We demonstrate that these alternatives are better suited to the recovery of smooth models, and show that the posterior probability solution is less susceptible to multimodalities which can complicate the interpretation of model parameter uncertainties.
Published: 2019
Full Text: View/download PDF

29. Assessing the robustness of Antarctic temperature reconstructions over the past 2 millennia using pseudoproxy and data assimilation experiments

Author: F. Klein, N. J. Abram, M. A. J. Curran, H. Goosse, S. Goursaud, V. Masson-Delmotte, A. Moy, R. Neukom, A. Orsi, J. Sjolte, N. Steiger, B. Stenni, M. Werner, UCL - SST/ELI/ELIC - Earth & Climate, Centre Georges Lemaître for Earth and Climate Research [Louvain] (TECLIM), Earth and Life Institute [Louvain-La-Neuve] (ELI), Université Catholique de Louvain = Catholic University of Louvain (UCL)-Université Catholique de Louvain = Catholic University of Louvain (UCL), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Australian Antarctic Division (AAD), Australian Government, Department of the Environment and Energy, 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), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), 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 de glaciologie et géophysique de l'environnement (LGGE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Antarctic Climate and Ecosystems Cooperative Research Centre (ACE-CRC), Oeschger Centre for Climate Change Research (OCCR), University of Bern, Lund University [Lund], Lamont-Doherty Earth Observatory (LDEO), Columbia University [New York], University of Ca’ Foscari [Venice, Italy], Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), 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), and 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)
Subjects: 010506 paleontology, 010504 meteorology & atmospheric sciences, δ18O, lcsh:Environmental protection, Stratigraphy, 01 natural sciences, Data assimilation, Ice core, lcsh:Environmental pollution, lcsh:TD169-171.8, 14. Life underwater, 910 Geography & travel, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Global and Planetary Change, Paleontology, 550 Earth sciences & geology, lcsh:Environmental sciences, 0105 earth and related environmental sciences, lcsh:GE1-350, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Coupled model intercomparison project, Palaeontology, Pseudoproxy, Covariance, 13. Climate action, Settore GEO/08 - Geochimica e Vulcanologia, Paleoclimate Modelling Intercomparison Project, Climatology, lcsh:TD172-193.5, Climate model, Geology
Abstract: The Antarctic temperature changes over the past millennia remain more uncertain than in many other continental regions. This has several origins: (1) the number of high-resolution ice cores is small, in particular on the East Antarctic plateau and in some coastal areas in East Antarctica; (2) the short and spatially sparse instrumental records limit the calibration period for reconstructions and the assessment of the methodologies; (3) the link between isotope records from ice cores and local climate is usually complex and dependent on the spatial scales and timescales investigated. Here, we use climate model results, pseudoproxy experiments and data assimilation experiments to assess the potential for reconstructing the Antarctic temperature over the last 2 millennia based on a new database of stable oxygen isotopes in ice cores compiled in the framework of Antarctica2k (Stenni et al., 2017). The well-known covariance between δ18O and temperature is reproduced in the two isotope-enabled models used (ECHAM5/MPI-OM and ECHAM5-wiso), but is generally weak over the different Antarctic regions, limiting the skill of the reconstructions. Furthermore, the strength of the link displays large variations over the past millennium, further affecting the potential skill of temperature reconstructions based on statistical methods which rely on the assumption that the last decades are a good estimate for longer temperature reconstructions. Using a data assimilation technique allows, in theory, for changes in the δ18O–temperature link through time and space to be taken into account. Pseudoproxy experiments confirm the benefits of using data assimilation methods instead of statistical methods that provide reconstructions with unrealistic variances in some Antarctic subregions. They also confirm that the relatively weak link between both variables leads to a limited potential for reconstructing temperature based on δ18O. However, the reconstruction skill is higher and more uniform among reconstruction methods when the reconstruction target is the Antarctic as a whole rather than smaller Antarctic subregions. This consistency between the methods at the large scale is also observed when reconstructing temperature based on the real δ18O regional composites of Stenni et al. (2017). In this case, temperature reconstructions based on data assimilation confirm the long-term cooling over Antarctica during the last millennium, and the later onset of anthropogenic warming compared with the simulations without data assimilation, which is especially visible in West Antarctica. Data assimilation also allows for models and direct observations to be reconciled by reproducing the east–west contrast in the recent temperature trends. This recent warming pattern is likely mostly driven by internal variability given the large spread of individual Paleoclimate Modelling Intercomparison Project (PMIP)/Coupled Model Intercomparison Project (CMIP) model realizations in simulating it. As in the pseudoproxy framework, the reconstruction methods perform differently at the subregional scale, especially in terms of the variance of the time series produced. While the potential benefits of using a data assimilation method instead of a statistical method have been highlighted in a pseudoproxy framework, the instrumental series are too short to confirm this in a realistic setup.
Published: 2019
Full Text: View/download PDF

30. Pre-Ribosomal RNA Processing in Human Cells: From Mechanisms to Congenital Diseases

Author: Simon Lebaron, Maxime Aubert, Marie-Françoise O'Donohue, Pierre-Emmanuel Gleizes, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Laboratoire de biologie moléculaire eucaryote (LBME), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre de Biologie Intégrative (CBI), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Diamond–Blackfan anemia, Ribosomal Proteins, [SDV]Life Sciences [q-bio], lcsh:QR1-502, Review, [SDV.BC]Life Sciences [q-bio]/Cellular Biology, Biology, Primary transcript, Biochemistry, Ribosome, lcsh:Microbiology, 03 medical and health sciences, exonucleases, medicine, Protein biosynthesis, Humans, Disease, RNA Processing, Post-Transcriptional, Molecular Biology, Organism, ribosomopathies, ComputingMilieux_MISCELLANEOUS, 030304 developmental biology, 0303 health sciences, ribosomal stress, 030305 genetics & heredity, RNA, Ribosomal RNA, medicine.disease, ribosomal RNAs (rRNAs), endonucleases, Cell biology, RNA processing, RNA, Ribosomal, Nucleic Acid Conformation, RNA Cleavage, Ribosomes
Abstract: Ribosomal RNAs, the most abundant cellular RNA species, have evolved as the structural scaffold and the catalytic center of protein synthesis in every living organism. In eukaryotes, they are produced from a long primary transcript through an intricate sequence of processing steps that include RNA cleavage and folding and nucleotide modification. The mechanisms underlying this process in human cells have long been investigated, but technological advances have accelerated their study in the past decade. In addition, the association of congenital diseases to defects in ribosome synthesis has highlighted the central place of ribosomal RNA maturation in cell physiology regulation and broadened the interest in these mechanisms. Here, we give an overview of the current knowledge of pre-ribosomal RNA processing in human cells in light of recent progress and discuss how dysfunction of this pathway may contribute to the physiopathology of congenital diseases.
Published: 2018
Full Text: View/download PDF

31. Primary Silica-rich Picrite and High-Ca Boninite Melt Inclusions in Pyroxenite Veins from the Kamchatka Sub-arc Mantle

Author: Dmitri A. Ionov, Oliver Nebel, N. Shimizu, Richard J. Arculus, Nicole Métrich, Antoine Bénard, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Géosciences Montpellier, Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Woods Hole Oceanographic Institution (WHOI), Institut de Physique du Globe de Paris (IPGP), 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), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Université des Antilles (UA)-Centre National de la Recherche Scientifique (CNRS), and 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)
Subjects: 010504 meteorology & atmospheric sciences, Mantle wedge, partial melting, Geochemistry, island arc, melt inclusions, 010502 geochemistry & geophysics, Picrite basalt, 01 natural sciences, Mantle (geology), high field strength elements, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Geochemistry and Petrology, boninite, Xenolith, Petrology, Amphibole, 0105 earth and related environmental sciences, Melt inclusions, Partial melting, picrite, mantle wedge, Geophysics, 13. Climate action, Websterite, mantle xenolith, subduction, Geology, pyroxenite
Abstract: International audience; Island arc picrites and boninites are magnesian magmatic rocks believed to be generated by high degrees of melting of depleted mantle sources fluxed by subduction-derived, volatile-rich components. These magmas can be probes of both the mantle wedge protoliths and subduction components, but are rare among other, usually more evolved, types of arc lavas. Furthermore, many arc picrites and boninites show evidence for late-stage differentiation prior to or during eruption, masking their primary, mantle-derived geochemical signatures. We report textural and chemical data on spinel-hosted melt inclusions of mantle origin in amphibole-bearing websterite veins cross-cutting spinel harzburgite xenoliths from the active andesitic Avacha volcano (south Kamchatka, Russia). The data are used to constrain the composition and origin of melts that formed the websterite veins in the sub-arc lithospheric mantle. The melt inclusions typically contain euhedral orthopyroxene and clinopyroxene and occasionally minor amphibole in silicate glass. The melt inclusions were homogenized using heating stages and gas-mixing furnaces. The homogenized glasses range from subalkaline primitive silica-rich picrite and high-Ca boninite (>15 wt % MgO, 48–54 wt % SiO2) to rhyolite. High-Ca boninite glasses have moderate volatile and low heavy rare earth element contents and elevated Cs, Rb, Ba, U, Sr, and Li abundances, with extremely high U/Th. In turn, the glasses display no negative spikes in the high field strength elements Nb, Ta, Zr, Hf, and Ti. We show that the silica-rich picrite and high-Ca boninite liquids in this study formed by high degrees of melting (>25%), at volatile under-saturation, of hybrid melt-depleted but silica-rich mantle sources at ≥1·5 GPa. The hybrid sources formed in two stages: first, by extraction of ∼15% melt from the convecting mantle to form a refractory protolith, which was subsequently enriched in silica via interaction with subduction-derived components prior to or during remelting in the mantle wedge. The subduction-derived components were enriched in fluid-mobile elements and probably oxidized. Overall, our results suggest that silica-rich picrites and high-Ca boninites can be primary melts in mature subduction zones and differentiate within the mantle wedge and the deep arc crust to form more evolved andesite magmas.
Published: 2016
Full Text: View/download PDF

32. A comprehensive chronology of the Neanderthal site Moula-Guercy, Ardèche, France

Author: Emmanuel Desclaux, Malte Willmes, Leslie Kinsley, Evelyne Crégut-Bonnoure, Alban Defleur, Véronique Michel, Fang Fang, Alexa Benson, Rainer Grün, Thibaud Saos, Katerina Douka, Richard Armstrong, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Research School of Earth Sciences and Research School of Pacific and Asian Studies, University of Oxford [Oxford], Culture et Environnements, Préhistoire, Antiquité, Moyen-Age (CEPAM), Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), Géoazur (GEOAZUR 7329), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Museum Requien, Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), Laboratoire Départemental de Préhistoire du Lazaret (LDPL), Département des Alpes-Maritimes, Karolinska Institutet [Stockholm], Histoire naturelle de l'Homme préhistorique (HNHP), Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN), Aix-Marseille Université - Faculté de médecine (AMU MED), Aix Marseille Université (AMU), 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), University of Oxford, Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Muséum national d'Histoire naturelle (MNHN)-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), 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: 010506 paleontology, Archeology, geography, geography.geographical_feature_category, Neanderthal, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, 010504 meteorology & atmospheric sciences, biology, Biostratigraphy, 01 natural sciences, law.invention, Sequence (geology), Paleontology, Cave, Stratigraphy, law, biology.animal, Radiocarbon dating, Tephra, ComputingMilieux_MISCELLANEOUS, Geology, 0105 earth and related environmental sciences, Chronology
Abstract: The Baume (cave) Moula-Guercy, in southeast France, contains an important sedimentary sequence, which includes the remains of a cannibalised group of Neanderthals. The chronology of the upper layers of the cave is currently constrained by a thermoluminescence date of 72 ± 12 ka, obtained from a tephra deposit (layer VI). The middle and lower layers of the cave have been constrained by biostratigraphy, pointing towards the end of MIS 5 for the Neanderthal bearing layer XV. In order to refine the chronology of the site, we applied radiocarbon, 40Ar/39Ar, U-series and ESR dating analyses. Radiocarbon dates on bone samples from layer IV showed ages older than 50 ka. 40Ar/39Ar dating on sanidines from tephra of layer VI revealed, that these volcanic minerals derived probably from the Hercynian basement, and thus provided no tangible chronological constrain. Combined CSUS/ESR results on faunal teeth place layer IV at the end of MIS 3 to MIS 4, in agreement with the radiocarbon dates and in stratigraphic order with the thermoluminescence age for layer VI. Layer VIII, with only one sample, is tentatively placed to the end of MIS 4. The age estimates for layer XIV are not conclusive, preventing an age estimation for this layer. The younger age result for layer XIV does not agree with the stratigraphy and biostratigraphy of the site and more direct dating of material from this layer is needed to resolve this discrepancy. Located just below, the crucial Neanderthal bearing layer XV is placed to the end of MIS 5 and younger than MIS 6, in agreement with the climatological and chronological deductions from the stratigraphy and biostratigraphy of the site. Direct U-series analyses on two Neanderthal teeth agree with an age for layer XV corresponding to at least MIS 5 sensu lato. The U-series results on the Neanderthal tooth 3525 show that U-mobilisation even into small teeth is highly complex, but nevertheless give an indication that this sample corresponds to MIS 5e. This is in agreement with the CSUS/ESR results from faunal teeth as well as the stratigraphy and biostratigraphy of the cave. The refined chronology corroborates the existing stratigraphic and biostratigraphic framework. Moula-Guercy layer XV, with its many human remains showing cannibalism, now stands as a reference site for this particular aspect of human behaviour.
Published: 2016
Full Text: View/download PDF

33. The Ranger uranium deposit, northern Australia: Timing constraints, regional and ore-related alteration, and genetic implications for unconformity-related mineralisation

Author: Roger G. Skirrow, Tehani Kuske, Richard Armstrong, Etienne Deloule, Julien Mercadier, Geoscience Australia, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), GeoRessources, Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL)-Centre de recherches sur la géologie des matières premières minérales et énergétiques (CREGU)-Institut national des sciences de l'Univers (INSU - CNRS), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Centre de Recherches Pétrographiques et Géochimiques (CRPG), and Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Unconformity-related uranium deposits, 010504 meteorology & atmospheric sciences, Metamorphic rock, Geochronology, Geochemistry, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, chemistry.chemical_element, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Hydrothermal alteration, Pine Creek Orogen, Petrography, Uraninite, Geochemistry and Petrology, Titanite, Breccia, Metasomatism, 0105 earth and related environmental sciences, Geology, Uranium, Uranium ore, chemistry, Ranger 1 deposit, engineering, Economic Geology
Abstract: The Ranger 1 unconformity-related uranium deposit in the Northern Territory of Australia is one of the world's largest uranium deposits and has ranked in the top two Australian producers of uranium in recent years. Mineralisation at the Ranger, Jabiluka and other major unconformity-related deposits in the Alligator Rivers Uranium Field (ARUF) occurs in Paleoproterozoic metamorphic basement rocks immediately beneath the unconformity with the Paleo- to Mesoproterozoic McArthur Basin. The sites of uranium mineralisation and associated alteration at the Ranger 1 deposit (Number 3 orebody) were fundamentally controlled by reactivated shear zones that were initiated during the regional Nimbuwah tectonothermal event. The timing of shearing at medium metamorphic grade was constrained by ion microprobe U–Pb dating of zircons in two pegmatites, one weakly foliated (1867.0 ± 3.5 Ma) and another that is unfoliated and cuts the shear fabric (1862.8 ± 3.4 Ma). The younger age of ~ 1863 Ma represents the minimum age of D1 shearing during the Nimbuwah event at the Ranger 1 deposit (Number 3 orebody). Titanite within veins of amphibole-plagioclase-apatite yielded an ion microprobe U–Pb age of 1845.4 ± 4.2 Ma, which represents a previously unrecognised hydrothermal event in the ARUF. Based on previous data, retrograde hydrothermal alteration during D2 reactivation of D1 shear zones is interpreted to have occurred at ~ 1800 Ma during the regional Shoobridge tectonothermal event. Detailed paragenetic observations supported by whole-rock geochemical data from the Ranger 1 deposit (Number 3 orebody) reveal a sequence of post-D2 hydrothermal events, as follows. (1) Intense magnesium-rich chlorite alteration and brecciation, focussed within schists of the Upper Mine Sequence in the Cahill Formation. (2) Silicification of Lower Mine Sequence carbonate rock units and overlying schist units, comprising quartz ± Mg-foitite (tourmaline) ± muscovite ± pyrite ± marcasite, and rare uraninite (early U1). (3) Formation of main stage uranium ore and heterolithic breccias including clasts of olivine–phyric dolerite, with breccia matrix composed of uraninite (U1), Mg-chlorite ± Mg-foitite and minor pyrite and chalcopyrite. (4) A second generation of uraninite (U2) veinlets with disordered graphitic carbon and quartz of hydrothermal origin. (5) Late-stage veinlets of massive uraninite (U3). As inferred in a previous study and confirmed herein, olivine–phyric dolerite dykes at Ranger are mineralised and chloritised, and are geochemically similar to the regional Oenpelli Dolerite. A maximum age for uranium mineralisation at the Ranger 1 deposit is therefore set by the age of the Oenpelli Dolerite (~ 1723 Ma). In-situ ion microprobe U–Pb analysis of texturally oldest U1 uraninite yielded a discordia array with a 206 Pb/ 238 U- 207 Pb/ 235 U upper intercept age of 1688 ± 46 Ma. The oldest individual ion microprobe 207 Pb– 206 Pb age is 1684 ± 7 Ma whereas the oldest age determined by in-situ electron microprobe chemical dating of U1 uraninite is ~ 1646 Ma. Another sample containing both U1 and U2 uraninite yielded discordant data with a 206 Pb/ 238 U– 207 Pb/ 235 U upper intercept age of 1421 ± 68 Ma. When the 207 Pb/ 206 Pb ages are considered the data are suggestive of U2 uraninite formation and possible resetting of the U1 age between ~ 1420 Ma and ~ 1040 Ma. All ion microprobe analyses of U1 and U2 uraninite indicate variable and possibly repeated lead loss. In contrast ion microprobe U–Pb dating of the third generation of uraninite (U3) yielded several near-concordant analyses and a 206 Pb/ 238 U– 207 Pb/ 235 U upper intercept age of 474 ± 6 Ma. This age is supported by electron microprobe chemical ages of U3 uraninite between 515 Ma and 385 Ma. The new results constrain the timing of initial uranium mineralisation at the Ranger 1 deposit (Number 3 orebody) to the period ~ 1720 Ma to ~ 1680 Ma, which just overlaps with a previous U–Pb age of 1737 ± 20 Ma for uraninite-rich whole-rock samples. Our results are consistent with individual laser-ICPMS 207 Pb/ 206 Pb and chemical ages of uraninite as old as 1690–1680 Ma reported from other deposits and prospects in the ARUF. Whole-rock geochemical data in this study of the Ranger 1 deposit (Number 3 orebody) and in other studies in the ARUF demonstrate that zones of intense chloritisation associated with uranium mineralisation experienced large metasomatic gains of Mg, U, Co, Ni, Cu and S and losses of Si, Na, Ca, Sr, Ba, K, Rb, Y and the light REE. More broadly in the ARUF, a regionally extensive illite–hematite ± kaolinite-bearing ‘paleoregolith’ zone in basement beneath the McArthur Basin exhibits depletion of about half of its uranium as well as major losses in Na, Sr, Pb, Ba and minor losses of Mg. These features together with new petrographic observations suggest this zone is a regional sub-McArthur Basin alteration zone produced by interaction with diagenetic or hydrothermal fluids of primary basinal origin, rather than representing a low-temperature paleo-weathering zone before the deposition of the McArthur Basin, as previously suggested. Based on these results and a synthesis of previous work, a new multi-stage model is proposed for the Ranger 1 ore-forming mineral system that may apply to other major unconformity-related uranium deposits in the ARUF and which may be used for targeting new deposits in the region. As in most recent models, oxidised diagenetic brines within the McArthur Basin are envisaged as crucial in mobilising uranium. However, a different architecture of fluid flow is proposed involving the sub-unconformity regional basement alteration zone as a preferential source of leached uranium. Possibly driven by convection during regional magmatism at ~ 1725–1705 Ma, oxidised basinal brines were drawn downwards and laterally through fault networks and fractures in the regional sub-unconformity alteration zone, leaching uranium from hematite-altered basement rocks. Simultaneously within deeper and lateral parts of the hydrothermal system, Mg-metasomatism produced chloritic alteration and brines with increased acidity and silica content (from the desilicification of the basement rock), analogous to processes described in sub-seafloor hydrothermal systems. Silicification occurred locally (e.g., Ranger deposit) within upflow zones of convective systems due to decreases in temperature and/or pressure of the brines and/or CO 2 generation during carbonate dissolution. Interruptions to convection during transient regional extensional or strike-slip tectonic events resulted in generalised lateral and downwards flow of fluids from the McArthur Basin through deepened zones of sub-unconformity alteration, transferring leached uranium into reactivated shear zones within the basement. The main stage of uraninite precipitation at the Ranger deposit and elsewhere in the ARUF is proposed to have occurred between ~ 1720 Ma and ~ 1680 Ma as a result of reduction of oxidised and evolved basin-derived ore fluids during reaction with pre-existing Fe 2 + -bearing minerals and/or mixing of the ore fluids with basement-reacted silica-rich brines. A second, volumetrically minor but locally high-grade, stage of uraninite mineralisation was associated with hydrothermal disordered carbon and quartz of presently unknown origin. Available data suggest formation between ~ 1420 Ma and ~ 1040 Ma. Almost a billion years later at ~ 475 Ma, fluids capable of mobilising uranium again resulted in uraninite (U3) deposition as sparse veinlets in the Ranger deposit, representing the first documentation of uranium mineralisation of this age in the region.
Published: 2016
Full Text: View/download PDF

34. Improvement of laser ablation in situ micro-analysis to identify diagenetic alteration and measure strontium isotope ratios in fossil human teeth

Author: Leslie Kinsley, Malte Willmes, Maxime Aubert, Stephen Eggins, Rainer Grün, Marie-Hélène Moncel, Richard Armstrong, Research School of Earth Sciences [Canberra] (RSES), and Australian National University (ANU)
Subjects: Archeology, Strontium, Laser ablation, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, Enamel paint, Isotope, Chemistry, 010401 analytical chemistry, Analytical technique, Analytical chemistry, chemistry.chemical_element, Mineralogy, 010502 geochemistry & geophysics, Tooth enamel, 01 natural sciences, Isotopes of strontium, 0104 chemical sciences, medicine.anatomical_structure, stomatognathic system, visual_art, visual_art.visual_art_medium, medicine, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Isotope analysis
Abstract: Strontium isotope ratios measured in fossil human teeth are a powerful tool to investigate past mobility patterns. In order to apply this method, the sample needs to be investigated for possible diagenetic alteration and a least destructive analytical technique needs to be employed for the isotopic analysis. We tested the useability of U, Th, and Zn distribution maps to identify zones of diagenetic overprint in human teeth. Areas with elevated U concentrations in enamel were directly associated with diagenetic alterations in the Sr isotopic composition. Once suitable domains within the tooth are identified, strontium isotope ratios can be determined either with micro-drilling followed by TIMS analysis or in situ LA-MC-ICP-MS. Obtaining accurate 87Sr/86Sr isotope ratios from LA-MC-ICP-MS is complicated by the potential occurrence of a significant direct interference on mass 87 from a polyatomic compound. We found that this polyatomic compound is present in our analytical setup but is Ar rather than Ca based, as was previously suggested. The effect of this interference can be significantly reduced by tuning the instrument for reduced oxide levels. We applied this improved analytical protocol to a range of human and animal teeth and compared the results with micro-drilling strontium isotopic analysis using TIMS. Tuning for reduced oxide levels allowed the measurement of accurate strontium isotope ratios from human and animal tooth enamel and dentine, even at low Sr concentrations. The average offset between laser ablation and solution analysis using the improved analytical protocol is 38 ± 394 ppm (n = 21, 2σ). LA-MC-ICP-MS thus provides a powerful alternative to micro-drilling TIMS for the analysis of fossil human teeth. This method can be used to untangle diagenetic overprint from the intra-tooth isotopic variability, which results from genuine changes in 87Sr/86Sr isotope ratios related to changes in food source, and by extension mobility.
Published: 2016
Full Text: View/download PDF

35. Mitigating Human IAPP Amyloidogenesis In Vivo with Chiral Silica Nanoribbons

Author: Sijie Lin, Reiko Oda, Feng Ding, Ava Faridi, Pouya Faridi, Mei Zhao, Thomas P. Davis, Anthony W. Purcell, Jie Gao, Guotao Peng, Aleksandr Kakinen, Yutaka Okazaki, Yunxiang Sun, Pu Chun Ke, Ibrahim Javed, Department of Applied Chemistry and Biochemistry, Kumamoto University, Research Centre for Plant RNA Signaling, College of Life and Environmental Sciences, Hangzhou Normal University, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Chimie et Biologie des Membranes et des Nanoobjets (CBMN), École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut de Chimie du CNRS (INC)-Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), Nanjing University of Aeronautics and Astronautics [Nanjing] (NUAA), Institut Européen de Chimie et Biologie (IECB), and Université de Bordeaux (UB)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: silica nanoribbons, Amyloid, [SDV]Life Sciences [q-bio], Nucleation, chirality, Peptide, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Article, Biomaterials, chemistry.chemical_compound, Amyloid disease, In vivo, Humans, General Materials Science, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, amyloidogenesis, Viability assay, chemistry.chemical_classification, Chemistry, Nanotubes, Carbon, toxicity, Stereoisomerism, [CHIM.MATE]Chemical Sciences/Material chemistry, General Chemistry, 021001 nanoscience & nanotechnology, Silicon Dioxide, 0104 chemical sciences, Islet Amyloid Polypeptide, human IAPP, silica nanoribbons, chirality, toxicity, amyloidogenesis, Biophysics, Thioflavin, human IAPP, 0210 nano-technology, Chirality (chemistry), Biotechnology
Abstract: International audience; Amyloid fibrils generally display chirality, a feature which has rarely been exploited in the development of therapeutics against amyloid diseases. This study reports, for the first time, the use of mesoscopic chiral silica nanoribbons against the in vivo amyloidogenesis of human islet amyloid polypeptide (IAPP), the peptide whose aggregation is implicated in type 2 diabetes. The thioflavin T assay and transmission electron microscopy show accelerated IAPP fibrillization through elimination of the nucleation phase and shortening of the elongation phase by the nanostructures. Coarse-grained simulations offer complementary molecular insights into the acceleration of amyloid aggregation through their nonspecific binding and directional seeding with the nanostructures. This accelerated IAPP fibrillization translates to reduced toxicity, especially for the right-handed silica nanoribbons, as revealed by cell viability, helium ion microscopy, as well as zebrafish embryo survival, developmental, and behavioral assays. This study has implicated the potential of employing chiral nanotechnologies against the mesoscopic enantioselectivity of amyloid proteins and their associated diseases.
Published: 2018
Full Text: View/download PDF

36. Wintertime stress, nursing, and lead exposure in Neanderthal children

Author: Dani Dumitriu, Tanya M. Smith, Rachel Wood, Christine Austin, Shara E. Bailey, Rainer Grün, Renaud Joannes-Boyau, Stewart Fallon, Daniel R. Green, Hannah F. James, Manish Arora, Marie-Hélène Moncel, Ian S. Williams, Chemistry, Department of Human Evolution [Leipzig], Max Planck Institute for Evolutionary Anthropology [Leipzig], Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Southern Cross GeoScience, Southern Cross University (SCU), Biological Sciences, Columbia University [New York], Australian National University (ANU), Research School of Earth Sciences and Research School of Pacific and Asian Studies, Histoire naturelle de l'Homme préhistorique (HNHP), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Research School of Earth Sciences [Canberra] (RSES), Physics of Fluids, University of Twente [Netherlands], Max Planck Institute for Evolutionary Anthropology, Southern Cross GeoScience, Southern Cross University, Military Road, PO Box 157, Lismore, NSW 2480, Australia, Southern Cross University, and Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)
Subjects: 010506 paleontology, Neanderthal, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, Climate change, 010502 geochemistry & geophysics, 01 natural sciences, [SHS]Humanities and Social Sciences, stomatognathic system, biology.animal, Animals, Research Articles, ComputingMilieux_MISCELLANEOUS, Neanderthals, 0105 earth and related environmental sciences, Multidisciplinary, biology, Fossils, Ecology, Radiometric Dating, SciAdv r-articles, Environmental Exposure, Environmental variation, 3. Good health, stomatognathic diseases, Geography, Animals, Newborn, Lead, Human evolution, 13. Climate action, general, Anthropology, Interglacial, Lead exposure, Seasons, Tooth, Research Article
Abstract: Elemental records in teeth reveal prehistoric seasons of Neanderthal birth, weaning, childhood illness, and neurotoxic exposures., Scholars endeavor to understand the relationship between human evolution and climate change. This is particularly germane for Neanderthals, who survived extreme Eurasian environmental variation and glaciations, mysteriously going extinct during a cool interglacial stage. Here, we integrate weekly records of climate, tooth growth, and metal exposure in two Neanderthals and one modern human from southeastern France. The Neanderthals inhabited cooler and more seasonal periods than the modern human, evincing childhood developmental stress during wintertime. In one instance, this stress may have included skeletal mobilization of elemental stores and weight loss; this individual was born in the spring and appears to have weaned 2.5 years later. Both Neanderthals were exposed to lead at least twice during the deep winter and/or early spring. This multidisciplinary approach elucidates direct relationships between ancient environments and hominin paleobiology.
Published: 2018
Full Text: View/download PDF

37. Erosion of the Southern Alps of New Zealand during the last deglaciation

Author: Faye E Nelson, Thierry Adatte, Olivier Beyssac, Ruohong Jiao, Simon C. Cox, Frédéric Herman, Helen L. Neil, German Research Centre for Geosciences - Helmholtz-Centre Potsdam (GFZ), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Institut de Géologie et d'Hydrogéologie, Université de Neuchâtel (UNINE), Department of Physics (Trinity College Dublin), Trinity College Dublin, National Institute of Water and Atmospheric Research [Wellington] (NIWA), and Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010504 meteorology & atmospheric sciences, [SDU]Sciences of the Universe [physics], Erosion, Deglaciation, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Geology, Physical geography, [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology, [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology, 010502 geochemistry & geophysics, 01 natural sciences, 0105 earth and related environmental sciences
Abstract: During the Quaternary, periodic glaciations transformed mountain landscapes. However, characterizing the way in which mountain erosion changes between glacier- and river-dominated conditions has been elusive. Here, using samples from an offshore sedimentary core, we estimated the spatial distribution of erosion in the southern part of the Southern Alps of New Zealand during a full transition from the Last Glacial Maximum (LGM), ca. 20 ka, to the last millennium. Raman spectroscopy analyses of carbonaceous material revealed a marked change in the sediment provenance, which we interpreted to reflect the evolving erosion pattern of the mountain range. Over the Holocene, since at least ca. 9 ka, erosion was focused on the chlorite zone schist within the upper reaches of the valleys (>15–20 km distance from the mountain front), possibly dominated by large-magnitude landslides. During the last glaciation, the proportion of sediments from the biotite schist and higher-grade metamorphic rocks in the lower-lying areas closer to the mountain front (
Published: 2018
Full Text: View/download PDF

38. The IRHUM (Isotopic Reconstruction of Human Migration) database – bioavailable strontium isotope ratios for geochemical fingerprinting in France

Author: Maxime Aubert, Ian Moffat, Rainer Grün, Bruno Maureille, Malte Willmes, Christophe Falguères, Stephen Eggins, Richard Armstrong, Leslie Kinsley, Linda McMorrow, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Muséum national d'Histoire naturelle (MNHN), De la Préhistoire à l'Actuel : Culture, Environnement et Anthropologie (PACEA), Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), and Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, chemistry.chemical_element, Sample (statistics), Information repository, 010502 geochemistry & geophysics, computer.software_genre, 01 natural sciences, Archaeological science, préhistoire, 0601 history and archaeology, lcsh:Environmental sciences, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, lcsh:GE1-350, Strontium, 060102 archaeology, Database, lcsh:QE1-996.5, Sampling (statistics), 06 humanities and the arts, Isotopes of strontium, Data set, Metadata, lcsh:Geology, chemistry, General Earth and Planetary Sciences, Environmental science, computer
Abstract: Strontium isotope ratios (87Sr / 86Sr) are a key geochemical tracer used in a wide range of fields including archaeology, ecology, food and forensic sciences. These applications are based on the principle that the Sr isotopic ratios of natural materials reflect the sources of strontium available during their formation. A major constraint for current studies is the lack of robust reference maps to evaluate the source of strontium isotope ratios measured in the samples. Here we provide a new data set of bioavailable Sr isotope ratios for the major geologic units of France, based on plant and soil samples (Pangaea data repository doi:10.1594/PANGAEA.819142). The IRHUM (Isotopic Reconstruction of Human Migration) database is a web platform to access, explore and map our data set. The database provides the spatial context and metadata for each sample, allowing the user to evaluate the suitability of the sample for their specific study. In addition, it allows users to upload and share their own data sets and data products, which will enhance collaboration across the different research fields. This article describes the sampling and analytical methods used to generate the data set and how to use and access the data set through the IRHUM database. Any interpretation of the isotope data set is outside the scope of this publication.
Published: 2018
Full Text: View/download PDF

39. Pedo-sedimentary constituents as paleoenvironmental proxies in the Sudano-Sahelian belt during the Late Quaternary (southwestern Chad Basin)

Author: David Sebag, Nathalie Diaz, Pierre Deschamps, Geoffroy de Saulieu, Yannick Garcin, Pierre G. Valla, Eric P. Verrecchia, Georgina E. King, Frédéric Herman, Fabienne Dietrich, Alain Durand, Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Hydrosciences Montpellier (HSM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), University of Bern, Institut des Sciences de la Terre (ISTerre), 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])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire de Chimie Physique Macromoléculaire (LCPM), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Institute of Earth and Environmental Science [Potsdam], University of Potsdam = Universität Potsdam, Patrimoines Locaux et Gouvernance (PALOC), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD), 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), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Faculté de Géosciences et Environnement, Université de Lausanne = University of Lausanne (UNIL), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL), University of Potsdam, 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), Université de Lausanne (UNIL), Centre National de la Recherche Scientifique (CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU), 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 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), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), 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), and 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)
Subjects: 010506 paleontology, Archeology, 010504 meteorology & atmospheric sciences, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, EAU DU SOL, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, PALEOENVIRONNEMENT, Vertisol, 01 natural sciences, DATATION, law.invention, chemistry.chemical_compound, VERTISOL, law, ddc:550, CARBONATE, Radiocarbon dating, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, QUATERNAIRE, Global and Planetary Change, PEDOGENESE, Soil organic matter, Geology, Last Glacial Maximum, 15. Life on land, ISOTOPE RADIOACTIF, Pedogenesis, chemistry, PALEOCLIMAT, 13. Climate action, LUMINESCENCE, [SDE]Environmental Sciences, Carbonate, Sedimentary rock, Institut für Geowissenschaften, Physical geography, MOUSSON, Quaternary
Abstract: Climate and environmental changes since the Last Glacial Maximum in the tropical zone of West Africa are usually inferred from marine and continental records. In this study, the potential of carbonate pedo-sedimentary geosystems, i.e. Vertisol relics, to record paleoenvironmental changes in the southwestern part of Chad Basin are investigated. A multi-dating approach was applied on different pedogenic organo-mineral constituents. Optically stimulated luminescence (OSL) dating was performed on the soil K-rich feldspars and was combined with radiocarbon dating on both the inorganic (C-14(inorg)) and organic carbon (C-14(org)) soil fractions. Three main pedo-sedimentary processes were assessed over the last 20 ka BP: 1) the soil parent material deposition, from 18 ka to 12 ka BP (OSL), 2) the soil organic matter integration, from 11 cal ka to 8 cal ka BP (C-14(org)), and 3) the pedogenic carbonate nodule precipitation, from 7 cal ka to 5 cal ka BP (C-14(inorg)). These processes correlate well with the Chad Basin stratigraphy and West African records and are shown to be related to significant changes in the soil water balance responding to the evolution of continental hydrology during the Late Quaternary. The last phase affecting the Vertisol relics is the increase of erosion, which is hypothesized to be due to a decrease of the vegetation cover triggered by (i) the onset of drier conditions, possibly strengthened by (ii) anthropogenic pressure. Archaeological data from Far North Cameroon and northern Nigeria, as well as sedimentation times in Lake Tilla (northeastern Nigeria), were used to test these relationships. The increase of erosion is suggested to possibly occur between c. 3 cal ka and 1 cal ka BP. Finally, satellite images revealed similar geosystems all along the Sudano-Sahelian belt, and initial C-14(inorg) ages of the samples collected in four sites gave similar ages to those reported in this study. Consequently, the carbonate pedo-sedimentary geosystems are valuable continental paleoenvironmental archives and soil water balance proxies of the semiarid tropics of West Africa. (C) 2018 Elsevier Ltd. All rights reserved.
Published: 2018
Full Text: View/download PDF

40. Globally asynchronous sulphur isotope signals require re-definition of the Great Oxidation Event

Author: Ernesto Pecoits, Elodie Muller, Christophe Thomazo, Bryan A. Killingsworth, Pierre Cartigny, Vincent Busigny, Franck Baton, Tom Caquineau, Janaína N. Ávila, Martin J. Van Kranendonk, Trevor Ireland, Pascal Philippot, Svetlana G. Tessalina, Stefan V. Lalonde, Institut de Physique du Globe de Paris (IPGP), 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), Géosciences Montpellier, Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Université des Antilles (UA)-Centre National de la Recherche Scientifique (CNRS), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), 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), John de Laeter Centre for Isotope Research, Curtin University [Perth], Planning and Transport Research Centre (PATREC)-Planning and Transport Research Centre (PATREC), 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), School of Biological, Earth and Environmental Sciences [Sydney] (BEES), University of New South Wales [Sydney] (UNSW), Work supported by grants from the Programme National de Planétologie and the São Paulo Research Foundation (FAPESP, grant 2015/16235-2), from the European Union Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 708117, and from ARC DP140103393., ANR-11-IDEX-0005,USPC,Université Sorbonne Paris Cité(2011), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), and ANR-11-IDEX-0005-02/10-LABX-0023,UnivEarthS,Earth - Planets - Universe: observation, modeling, transfer(2011)
Subjects: Multidisciplinary, 010504 meteorology & atmospheric sciences, Atmospheric oxygen, Science, Earth science, Great Oxygenation Event, General Physics and Astronomy, Sulfur cycle, Weathering, General Chemistry, 010502 geochemistry & geophysics, Sulphur isotope, 01 natural sciences, General Biochemistry, Genetics and Molecular Biology, Article, Diagenesis, 13. Climate action, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Geochronology, lcsh:Q, Sedimentary rock, lcsh:Science, Geology, 0105 earth and related environmental sciences
Abstract: The Great Oxidation Event (GOE) has been defined as the time interval when sufficient atmospheric oxygen accumulated to prevent the generation and preservation of mass-independent fractionation of sulphur isotopes (MIF-S) in sedimentary rocks. Existing correlations suggest that the GOE was rapid and globally synchronous. Here we apply sulphur isotope analysis of diagenetic sulphides combined with U-Pb and Re-Os geochronology to document the sulphur cycle evolution in Western Australia spanning the GOE. Our data indicate that, from ~2.45 Gyr to beyond 2.31 Gyr, MIF-S was preserved in sulphides punctuated by several episodes of MIF-S disappearance. These results establish the MIF-S record as asynchronous between South Africa, North America and Australia, argue for regional-scale modulation of MIF-S memory effects due to oxidative weathering after the onset of the GOE, and suggest that the current paradigm of placing the GOE at 2.33–2.32 Ga based on the last occurrence of MIF-S in South Africa should be re-evaluated., The Great Oxidation Event (GOE) is considered to have occurred at 2.33–2.32 Ga based on the last occurrence of MIF-S in South Africa. Here, based on sulphur isotope analysis of samples from Western Australia, the authors show preservation of MIF-S beyond 2.31 Ga and call for a re-evaluation of GOE timing.
Published: 2018
Full Text: View/download PDF

41. Evidence in Variscan Corsica of a brief and voluminous Late Carboniferous to Early Permian volcanic-plutonic event contemporaneous with a high-temperature/low-pressure metamorphic peak in the lower crust

Author: Alain Cocherie, Philippe Rossi, C. Mark Fanning, Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Research School of Earth Sciences [Canberra] (RSES), and Australian National University (ANU)
Subjects: Upper Carboniferous, Alkaline, geography, geography.geographical_feature_category, Felsic, Continental crust, Lower Permian, Batholith, Corsica, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Metamorphism, Geology, Magma chamber, 15. Life on land, High temperature, Granulite, Volcanic rock, Calc-alkaline, Paleontology, U-Pb zircon dating, Southern Variscan realm, Volcano-plutonic relationship, Zircon
Abstract: The U2 group of plutonic rocks constituting the main exposed part of the Corsica-Sardinia batholith (CSB) was emplaced from 308 to 275 Ma (the early Visean U1 group of Mg-K intrusions is not considered here). Field evidence earlier established volcanic-plutonic relationships in the U2 group of calc-alkaline intrusions of the CSB, though detailed chronological data were still lacking. Large outcrops of U2 volcanic formations are restricted to the less eroded zone north-west of the Porto-Ponte Leccia line in Corsica, but volcanic and volcano-sedimentary formations were widely eroded elsewhere since Permian times. They probably covered most of the batholith before the Miocene, as testified by the volcanic nature of the pebbles that form much of the Early Miocene conglomerates of eastern Corsica. U-Pb zircon dating (SHRIMP) was used for deciphering the chronology and duration of different volcanic pulses and for better estimating the time overlap between plutonic and volcanic rock emplacement in the CSB. The obtained ages fit well with field data, showing that most of the U2 and U3 volcanic formations were emplaced within a brief time span of roughly 15 m.y., from 293 to 278 Ma, coeval with most U2 monzogranodiorites and leucomonzogranites (295–280 Ma), alkaline U3 complexes (about 288 Ma), and mafic-ultramafic tholeiitic complexes (295–275 Ma). The same chronological link between deep-seated magma chambers and eruptions was identified in the Pyrenees. These results correlate with U-Pb zircon dating of HT-LP granulites from the Variscan deep crust exhumed along the “European” margin of the thinned Tethys margin in Corsica and Calabria. Here, the peak of the low-pressure/high-temperature metamorphism was dated at about 285–280 Ma. Our results throw light on the condition of magma production during the orogenic collapse in the southern Variscan realm. While juvenile tholeiitic basaltic magma was produced by the melting of spinel mantle lithosphere, all fertile protoliths melted in a brief period during the HT-LP peak in lower continental crust, leading to massive emplacement of large felsic U2 calc-alkaline and minor U3 A-type volcano-plutonic formations over about 15 Ma.
Published: 2015
Full Text: View/download PDF

42. Solubility and speciation of REE in high temperature fluids: insights from in situ XAS studies

Author: Jean-Louis Hazemann, John Mavrogenes, Marion Louvel, Barbara Etschmann, Denis Testemale, Joël Brugger, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), School of Earth Sciences [Melbourne], Faculty of Science [Melbourne], University of Melbourne-University of Melbourne, Matériaux, Rayonnements, Structure (MRS), Institut Néel (NEEL), and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: In situ, X-ray absorption spectroscopy, 010504 meteorology & atmospheric sciences, Inorganic chemistry, Rare earth, 010502 geochemistry & geophysics, Geotechnical Engineering and Engineering Geology, 01 natural sciences, 13. Climate action, Geochemistry and Petrology, Genetic algorithm, Earth and Planetary Sciences (miscellaneous), [CHIM]Chemical Sciences, Solubility, Geology, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: The increasing demand for rare earth elements (La to Yb, +Sc and Y) from the green and communication industries calls for a better understanding of the processes leading to their concentration in t...
Published: 2017
Full Text: View/download PDF

43. Conodont apatite δ88/86Sr and δ44/40Ca compositions and implications for the evolution of Palaeozoic to early Mesozoic seawater

Author: K. Rankenburg, Malcolm T. McCulloch, Julie Trotter, Sandrine Le Houedec, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), School of Earth and Environment (UWA), and The University of Western Australia (UWA)
Subjects: Radiogenic nuclide, 010504 meteorology & atmospheric sciences, Paleozoic, biology, Stable isotope ratio, Geochemistry, Geology, 010502 geochemistry & geophysics, biology.organism_classification, 01 natural sciences, chemistry.chemical_compound, chemistry, 13. Climate action, Geochemistry and Petrology, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Ordovician, Carbonate, Seawater, Late Devonian extinction, Conodont, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: We present high precision (TIMS double spike) stable isotope measurements of both δ 44/40 Ca and δ 88/86 Sr together with radiogenic 87 Sr/ 86 Sr ratios determined from conodont apatite. These data represent five intervals ranging from the early Ordovician to late Triassic. The conodont δ 44/40 Ca values (relative to NIST 915a) range from − 0.47‰ to + 0.15‰, with an apparent shift to more positive values between the early Silurian and late Devonian/early Carboniferous, similar to the brachiopod-based marine δ 44/40 Ca record (Farkas et al., 2007a). We calculated a δ 44/40 Ca seawater-bio-apatite fractionation factor of about − 1.9‰, which allowed us to reconstruct a palaeo-seawater δ 44/40 Ca record from bio-apatites. Despite a slightly positive offset of about + 0.2 to + 0.5‰, the δ 44/40 Ca record obtained from bio-apatites is consistent with the previously reported δ 44/40 Ca seawater record inferred from carbonates. We find that unlike the carbonate δ 44/40 Ca records, the δ 88/86 Sr measurements from conodont apatite show unexpectedly large variations (up to ~ 1‰), with ratios ranging from − 0.6‰ to 0.3‰. These reconnaissance data reveal a reasonable correlation between δ 88/86 Sr and radiogenic 87 Sr/ 86 Sr* (r 2 = 0.60, n = 13, p = 0.002), suggesting that the controls from differential weathering regimes and/or continental crustal compositions buffered ancient seawater compositions.
Published: 2017
Full Text: View/download PDF

44. Geodynamic implications for zonal and meridional isotopic patterns across the northern Lau and North Fiji Basins

Author: Allison A. Price, Richard J. Arculus, Frances E. Jenner, Mark D. Kurz, Raul Brens, Janne Blichert-Toft, Matthew G. Jackson, James B. Gill, Jerzy S. Blusztajn, Laboratoire de Sciences de la Terre (LST), 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), Department of Marine Chemistry and Geochemistry (WHOI), Woods Hole Oceanographic Institution (WHOI), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), 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)-Centre National de la Recherche Scientifique (CNRS)
Subjects: geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Subduction, Lau Basin, Lineament, Geochemistry, Ocean island basalt, Structural basin, 010502 geochemistry & geophysics, 01 natural sciences, Plume, Geophysics, Oceanography, Volcano, 13. Climate action, Geochemistry and Petrology, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Hotspot (geology), 14. Life underwater, Geology, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: We present new Sr-Nd-Pb-Hf-He isotopic data for sixty-five volcanic samples from the northern Lau and North Fiji Basin. This includes forty-seven lavas obtained from forty dredge sites spanning an east-west transect across the Lau and North Fiji basins, ten ocean island basalt (OIB)-type lavas collected from seven Fijian islands, and eight OIB lavas sampled on Rotuma. For the first time we are able to map clear north-south and east-west geochemical gradients in 87Sr/86Sr across the northern Lau and North Fiji Basins: lavas with the most geochemically enriched radiogenic isotopic signatures are located in the northeast Lau Basin, while signatures of geochemical enrichment are diminished to the south and west away from the Samoan hotspot. Based on these geochemical patterns and plate reconstructions of the region, these observations are best explained by the addition of Samoa, Rurutu, and Rarotonga hotspot material over the past 4 Ma. We suggest that underplated Samoan material has been advected into the Lau Basin over the past ∼4 Ma. As the slab migrated west (and toward the Samoan plume) via rollback over time, younger and hotter (and therefore less viscous) underplated Samoan plume material was entrained. Thus, entrainment efficiency of underplated plume material was enhanced, and Samoan plume signatures in the Lau Basin became stronger as the trench approached the Samoan hotspot. The addition of subducted volcanoes to the Cook-Austral Volcanic Lineament material, first from the Rarotonga hotspot, then followed by the Rurutu hotspot, contributes to the extreme geochemical signatures observed in the northeast Lau Basin.
Published: 2017
Full Text: View/download PDF

45. Chlorine and fluorine partition coefficients and abundances in sub-arc mantle xenoliths (Kamchatka, Russia): Implications for melt generation and volatile recycling processes in subduction zones

Author: Mark A. Kendrick, Kenneth T. Koga, Richard J. Arculus, Antoine Bénard, N. Shimizu, Oliver Nebel, Dmitri A. Ionov, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Laboratoire Magmas et Volcans (LMV), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement et la société-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Université Jean Monnet [Saint-Étienne] (UJM), Woods Hole Oceanographic Institution (WHOI), Géosciences Montpellier, Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Université des Antilles (UA)-Centre National de la Recherche Scientifique (CNRS), Monash University, Centre National de la Recherche Scientifique and Institut National des Sciences de l’Univers (PNP project, theme SEDI-TPS to D. A.), the Australian Research Council (DE120100513 to O. N. and DP120104240 to R. J. A and O. N.), ANR-10-LABX-0006,CLERVOLC,Clermont-Ferrand centre for research on volcanism(2010), ANR-16-IDEX-0001,CAP 20-25,CAP 20-25(2016), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), and Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)
Subjects: Peridotite, 010504 meteorology & atmospheric sciences, Mantle wedge, Partial melting, Geochemistry, Partition coefficients, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Pyroxene, Fluorine, Subduction, 010502 geochemistry & geophysics, 01 natural sciences, Mantle (geology), peridotite, Island-arc, 13. Climate action, Geochemistry and Petrology, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Metasomatism, Chlorine, Geology, Amphibole, 0105 earth and related environmental sciences, Melt inclusions
Abstract: We report chlorine (Cl) and fluorine (F) abundances in minerals, interstitial glasses, and melt inclusions in 12 andesite-hosted, spinel harzburgite xenoliths and crosscutting pyroxenite veins exhumed from the sub-arc lithospheric mantle beneath Avacha volcano in the Kamchatka Arc (NE Russia). The data are used to calculate equilibrium mineral-melt partition coefficients ( D mineral / melt ) for Cl and F relevant to subduction-zone processes and unravel the history of volatile depletion and enrichment mechanisms in an arc setting. Chlorine is ∼100 times more incompatible in pyroxenes ( D Cl mineral / melt = 0.005–0.008 [±0.002–0.003]) than F ( D F mineral / melt = 0.50–0.57 [±0.21–0.24]), which indicates that partial melting of mantle sources leads to strong depletions in Cl relative to F in the residues. The data set in this study suggests a strong control of melt composition on D Cl , F pyroxene / melt , in particular H2O contents and Al/(Al + Si), which is in line with recent experiments. Fluorine is compatible in Ca-amphibole in the ‘wet’ sub-arc mantle ( D F amphibole / melt = 3.5–3.7 [±1.5]) but not Cl ( D Cl amphibole / melt = 0.03–0.05 [±0.01–0.03]), indicating that amphibole may fractionate F from Cl in the mantle wedge. The inter-mineral partition coefficients for Cl and F in this study are consistent amongst different harzburgite samples, whether they contain glass or not. In particular, disseminated amphibole hosts much of the Cl and F bulk rock budgets of spinel harzburgites ( D Cl amphibole / pyroxene up to 14 and D F amphibole / pyroxene up to 40). Chlorine and fluorine are variably enriched (up to 1500 ppm Cl and 750 ppm F) in the parental arc picrite and boninite melts of primitive pyroxenite veins (and related melt inclusions) crosscutting spinel harzburgites. Based on the data in this study, the main inferences on the behaviour of Cl and F during melting and metasomatic processes in the sub-arc mantle are as follow: (i) Melting models show that most depleted mantle protoliths of intra-oceanic arc sources can have extremely low Cl/F (0.002–0.007) before being overprinted by subduction-derived components. (ii) Chlorine has a higher percolation distance in the mantle than F. Even for small fluid or melt volumes, Cl and F signatures of partial melting are overprinted by those of pervasive percolation, which increases Cl/F in percolating agents and bulk peridotites during chromatographic interaction and/or amphibole-forming metasomatic reactions. These processes ultimately control the bulk Cl and F compositions of the residual mantle lithosphere beneath arcs, and likely in other tectonic settings. (iii) Fluxed melting models suggest that Cl enrichment in arc picrite and boninite melts in this study, and in many arc melt inclusions reported in the literature, could be related to the infiltration of high Cl/F fluids derived from subducted serpentinite or altered crust in mantle wedge sources. However, these high Cl/F signatures should be re-evaluated with new models in light of the possible overprint of pervasive percolation effects in the mantle. The breakdown of amphibole (and/or mica) in the deep metasomatised mantle at higher pressure and temperature conditions than in the slab may explain, at least in part, the positive correlations between F abundances and Cl/F in primitive arc melt inclusions and slab depth.
Published: 2017
Full Text: View/download PDF

46. Silica-enriched mantle sources of subalkaline picrite-boninite-andesite island arc magmas

Author: Dmitri A. Ionov, Oliver Nebel, Antoine Bénard, Richard J. Arculus, Sarlae R. B. McAlpine, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Monash University [Melbourne], Géosciences Montpellier, and Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Université des Antilles (UA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Peridotite, 010504 meteorology & atmospheric sciences, Mantle wedge, Geochemistry, Crust, Silica enrichment, Subduction, 010502 geochemistry & geophysics, 01 natural sciences, Mantle (geology), Picrite, 13. Climate action, Geochemistry and Petrology, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Hotspot (geology), Transition zone, Island arc, Xenolith, Geology, Primary melt, 0105 earth and related environmental sciences, Boninite
Abstract: Primary arc melts may form through fluxed or adiabatic decompression melting in the mantle wedge, or via a combination of both processes. Major limitations to our understanding of the formation of primary arc melts stem from the fact that most arc lavas are aggregated blends of individual magma batches, further modified by differentiation processes in the sub-arc mantle lithosphere and overlying crust. Primary melt generation is thus masked by these types of second-stage processes. Magma-hosted peridotites sampled as xenoliths in subduction zone magmas are possible remnants of sub-arc mantle and magma generation processes, but are rarely sampled in active arcs. Published studies have emphasised the predominantly harzburgitic lithologies with particularly high modal orthopyroxene in these xenoliths; the former characteristic reflects the refractory nature of these materials consequent to extensive melt depletion of a lherzolitic protolith whereas the latter feature requires additional explanation. Here we present major and minor element data for pristine, mantle-derived, lava-hosted spinel-bearing harzburgite and dunite xenoliths and associated primitive melts from the active Kamchatka and Bismarck arcs. We show that these peridotite suites, and other mantle xenoliths sampled in circum-Pacific arcs, are a distinctive peridotite type not found in other tectonic settings, and are melting residues from hydrous melting of silica-enriched mantle sources. We explore the ability of experimental studies allied with mantle melting parameterisations (pMELTS, Petrolog3) to reproduce the compositions of these arc peridotites, and present a protolith (‘hybrid mantle wedge’) composition that satisfies the available constraints. The composition of peridotite xenoliths recovered from erupted arc magmas plausibly requires their formation initially via interaction of slab-derived components with refractory mantle prior to or during the formation of primary arc melts. The liquid compositions extracted from these hybrid sources are higher in normative quartz and hypersthene (i.e., they have a more silica-saturated character) in comparison with basalts derived from prior melt-depleted asthenospheric mantle beneath ridges. These primary arc melts range from silica-rich picrite to boninite and high-Mg basaltic andesite along a residual spinel harzburgite cotectic. Silica enrichment in the mantle sources of arc-related, subalkaline picrite-boninite-andesite suites coupled with the amount of water and depth of melting, are important for the formation of medium-Fe (‘calc-alkaline’) andesite-dacite-rhyolite suites, key lithologies forming the continental crust.
Published: 2017
Full Text: View/download PDF

47. Deep crustal fracture zones control fluid escape and the seismic cycle in the Cascadia subduction zone

Author: Bruno Reynard, Benoit Tauzin, Jean-Philippe Perrillat, Eric Debayle, Thomas Bodin, 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), Laboratoire de Sciences de la Terre (LST), 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), Institut de physique du globe de Strasbourg (IPGS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), 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: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, 010504 meteorology & atmospheric sciences, Subduction, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Continental crust, North American Plate, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Crust, 010502 geochemistry & geophysics, 01 natural sciences, Geophysics, Space and Planetary Science, Geochemistry and Petrology, Receiver function, Earth and Planetary Sciences (miscellaneous), Episodic tremor and slip, Forearc, Seismology, Geology, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Terrane
Abstract: Seismic activity and non-volcanic tremors are often associated with fluid circulation resulting from the dehydration of subducting plates. Tremors in the overriding continental crust of several subduction zones suggest fluid circulation at shallower depths, but potential fluid pathways are still poorly documented. Using receiver function analysis in the Cascadia subduction zone, we provide evidence for a seismic discontinuity near 15 km depth in the crust of the overriding North American plate. This interface is segmented, and its interruptions are spatially correlated with conductive regions of the forearc and shallow swarms of seismicity and non-volcanic tremors. These observations suggest that fluid circulation in the overriding plate is controlled by fault zones separating blocks of accreted terranes. These zones constitute fluid escape routes that may influence the seismic cycle by releasing fluid pressure from the megathrust.
Published: 2017
Full Text: View/download PDF

48. Observation and modeling of the seismic seiches triggered in the Gulf of Corinth (Greece) by the 2011 M w 9.0 Tohoku earthquake

Author: Canitano, Alexandre, Bernard, Pascal, Allgeyer, Sébastien, Institute of Earth Sciences [Tapei] (IES Sinica), Academia Sinica, Institut de Physique du Globe de Paris (IPGP), 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), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), and CRLNET
Subjects: Greece, Tohoku earthquake, Gulf of Corinth, Basin oscillations, Numerical modeling, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Seismic seiches
Abstract: International audience; The study reports an unusual water level rise in the Gulf of Corinth, central Greece, during the passing of theseismic waves of the remote 2011 Mw 9.0 Tohoku earthquake. The seismic seiches were recorded by a tide-gaugelocated in the marina of the island of Trizonia, in the western side of the gulf. The cross-analysis between theground motion and the water level changes shows that seiching was initiated by the arrival of the earlier S-wavesand then enhanced by the surface waves. The seiching concerns five domains with periods ranging from minuteto about 7 min and with water level changes of a few millimeters to a few centimeters. The main seiching periodis about 5–7 min and the related water level has a maximum trough-to-peak amplitude of about 6–8 cm.Numerical simulation of the seismic seiches, based on the shallow water equations, allows us to model reasonablywell the amplitude of the seiches for most of the period domains, excepted those for the main seichingperiod at 7 min, which are underestimated by a factor of about 2–3. The largest bathymetric structures of thegulf to be excited in a seiche mode, with eigenperiods of hundreds of seconds, are a few kilometers in size.
Published: 2017
Full Text: View/download PDF

49. A Subsolidus Olivine Water Solubility Equation for the Earth's Upper Mantle

Author: PADRON NAVARTA, Jose Alberto, Hermann, J., Géosciences Montpellier, Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Université des Antilles (UA)-Centre National de la Recherche Scientifique (CNRS), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), and Universität Bern [Bern]
Subjects: deepwater cycle, hydrous defects, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], rheology, titanium, subduction zones, olivine, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
Abstract: International audience; The pressure and temperature sensitivity of the two most important point hydrous defects in mantle olivine involving Si vacancies (associated to trace amounts of titanium [TiChu‐PD] or exclusively to Si vacancies [Si]) was investigated at subsolidus conditions in a fluid‐saturated natural peridotite from 0.5 to 6 GPa (approximately 20–200 km depth) at 750 to 1050°C. Water contents in olivine were monitored in sandwich experiments with a fertile serpentine layer in the middle and olivine and pyroxene sensor layers at the border. Textures and mineral compositions provide evidence that olivine completely recrystallized during the weeklong experiments, whereas pyroxenes displayed only partial equilibration. A site‐specific water solubility law for olivine has been formulated based on the experiments reconciling previous contradictory results from low‐ and high‐pressure experiments. The site‐specific solubility laws permit to constrain water incorporation into olivine in the subducting slab and the mantle wedge, as these are rare locations on Earth where fluid‐present conditions exist. Chlorite dehydration in the hydrated slab is roughly parallel to the isopleth of 50 ± 20 ppm wt H2O in olivine, a value which is independent of the pressure and temperature trajectory followed by the slab. Hydrous defects are dominated by [Si] under the relevant conditions for the mantle wedge affected by fluids coming from the slab dehydration (slab‐adjacent low viscosity/seismic low‐velocity channel, P > 3 GPa). In cold subduction zones at 5.5 km from the slab surface the storage capacity of the mantle wedge at depths of 100–250 km ranges from 400 to 2,000 ppm wt H2O.
Published: 2017
Full Text: View/download PDF

50. Range expansion of the Asian native Giant Resin Bee Megachile sculpturalis in France

Author: Geslin, B., Aubert, M., Genoud, M., Andrieu-Ponel, Valérie, Westrich, P., Le Féon, V., Leydet, Michelle, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Research School of Earth Sciences [Canberra] (RSES), and Australian National University (ANU)
Subjects: [SDE] Environmental Sciences, [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2017

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Journal

Database

Publisher

148 results on '"Research School of Earth Sciences [Canberra] (RSES)"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources