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1. THE SPATIO-TEMPORAL VARIABILITY OF MAXIMUM FLOW IN THE UZ HYDROGRAPHICAL BASIN

Author: I.D. MIFTODE and GH. ROMANESCUAle xandru Ioan Cuza University of Iasi, Faculty of Geography and Geology, Department of Geography, Bd. Carol I
Subjects: maximum flow, maximum specific flow, Pearson III distribution low, exceeding probabilities, regionalization relations, Uz watershed, Meteorology. Climatology, QC851-999
Abstract: The analysis of the maximum flow, resulting from the influences of several miscellaneous control factors, leads to the empirical knowledge of the quantitative and qualitative hydrological characteristics of the rivers. The temporal and spatial variability of the maximum flow has been analyzed in this paper, based on the study of the monthly and annual maximum discharges recorded between 1985-2006, at the Valea Uzului, Cremenea, and Darmanesti hydrometric stations, in the Uz watershed. The data is provided by the Water Basin Administration Siret from Bacău which for this study was statistically processed. For the assessment of the maximum flows with different exceeding probabilities, the Pearson III empirical and theoretical curves have been utilized. The concluding results have been obtained using hydrologic regionalization relations; these take into account the specific maximum flows (qmaxp%) with different insurances, the average altitude (Hm) and the area (F) of the drainage basin (Hm/√F). By selecting maximum flows with values exceeding the flooding stage (FS), the occurrence frequency has been established in the studied area. The highest floods in the Uz hydrographical basin have occurred in the months of June-July.
Published: 2016
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2. The Permian–Triassic boundary section at Baghuk Mountain, Central Iran: carbonate microfacies and depositional environment

Author: Heuer, Franziska, Leda, Lucyna, Moradi-Salimi, Hemen, Gliwa, Jana, Hairapetian, Vachik, Korn, Dieter, Museum Für Naturkunde, Leibniz Institute for Research On Evolution and Biodiversity, Berlin, Germany, Geology Department, Faculty of Science, University of Isfahan, Isfahan, Iran, Eurasia Department and Beijing Branch Office, German Archaeological Institute, Berlin, Germany, and Department of Geology, Islamic Azad University, Isfahan (Khorasgan) BranchIsfahan, Iran
Subjects: Extinction event, Global and Planetary Change, Ecology, Permian, biology, Central Iran, ddc:563, Microbialites, Early Triassic, Geochemistry, Paleontology, Geology, biology.organism_classification, Permian–Triassic boundary, Claraia, Sedimentary depositional environment, chemistry.chemical_compound, chemistry, Sponges, Carbonate microfacies, Subaerial, Carbonate, Sedimentary rock, Ecology, Evolution, Behavior and Systematics
Abstract: Sections at Baghuk Mountain, 45 km NNW of Abadeh (Central Iran), have excellent exposures of fossiliferous marine Late Permian to Early Triassic sedimentary successions. Detailed bed-by-bed sampling enables the analysis of microfacies changes of three successive rock units across the Permian–Triassic boundary. The Late Permian Hambast Formation is mainly the result of biogenic carbonate production. Its carbonate microfacies is dominated by biogen-rich and bioturbated nodular limestones, indicating a well-oxygenated aphotic to dysphotic environment. The biogen-dominated carbonate factory in the Permian ceased simultaneously with the main mass extinction pulse, which is marked by a sharp contact between the Hambast-Formation and the overlaying Baghuk Member (= ‘Boundary Clay’). The clay and silt deposits of the Baghuk Member with some carbonate beds show only a few signs of bioturbation or relics of benthic communities. The Early Triassic Claraia Beds are characterised by a partly microbially induced carbonate production, which is indicated by frequent microbialite structures. The depositional environment does not provide evidence of large amplitude changes of sea level or subaerial exposure during the Permian–Triassic boundary interval. The deposition of the Baghuk Mountain sediments took place in a deep shelf environment, most of the time below the storm wave base., Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659, Museum für Naturkunde – Leibniz-Institut für Evolutions- und Biodiversitätsforschung (3498)
Published: 2021
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3. Evolution of the Lower Permian Rochlitz volcanic system, Eastern Germany: reconstruction of an intra-continental supereruption

Author: Hübner, Marcel, Breitkreuz, Christoph, Repstock, Alexander, Schulz, Bernhard, Pietranik, Anna, Lapp, Manuel, Heuer, Franziska, Institute of Geology, TU Bergakademie Freiberg, Freiberg, Germany, Saxon State Office for Environment, Agriculture and Geology, Department of Geology, Freiberg, Germany, Institute of Mineralogy, TU Bergakademie Freiberg, Freiberg, Germany, Institute of Geological Science, University of Wrocław, Wrocław, Poland, and Museum of Natural Science, Leibniz Institute for Research on Evolution and Biodiversity, Berlin, Germany
Subjects: Underplating, 010504 meteorology & atmospheric sciences, Lava, Geochemistry, Pyroclastic rock, 010502 geochemistry & geophysics, VEI 8 fissure eruption, 01 natural sciences, δ18O in zircon, Ti-in-biotite thermobarometer, Rhyolite, Magma, General Earth and Planetary Sciences, Caldera, Monotonous rhyolites, Magma mixing, ddc:552.2, Monotonous intermediates, Geology, Fiamme, 0105 earth and related environmental sciences, Zircon
Abstract: Extensional tectonics in the Late Paleozoic Central Europe was accompanied by rift magmatism that triggered voluminous intracontinental caldera-forming eruptions. Among these, the Lower Permian Rochlitz Volcanic System (RVS) in the North Saxon Volcanic Complex (Eastern Germany, Saxony) represents a supereruption (VEI 8, estimated volume of 1056 km3) of monotonous rhyolites followed by monotonous intermediates. Mapping, petrography, whole-rock geochemistry along with mineral chemistry and oxygen isotopes in zircon display its complex eruption history and magma evolution. Crystal-rich (> 35 vol%), rhyolitic Rochlitz-α Ignimbrite with strong to moderate welding compaction erupted in the climactic stage after reheating of the magma by basaltic injections. Due to magma mixing, low-volume trachydacitic-to-rhyolitic Rochlitz-β Ignimbrite succeeded, characterized by high Ti and Zr-values and zircon with mantle δ18O. Randomly oriented, sub-horizontally bedded fiamme, and NW–SE striking subvolcanic bodies and faults suggest pyroclastic fountaining along NW–SE-oriented fissures as the dominant eruption style. Intrusion of the Leisnig and the Grimma Laccoliths caused resurgence of the Rochlitz caldera forming several peripheral subbasins. In the post-climactic stage, these were filled with lava complexes, ignimbrites and alluvial to lacustrine sediments. Significant Nb and Ta anomalies and high Nb/Ta ratios (11.8–17.9) display a high degree of crustal contamination for the melts of the RVS. Based on homogenous petrographic and geochemical composition along with a narrow range of δ18O in zircon Rochlitz-α Ignimbrite were classified as monotonous rhyolites. For the Rochlitz-β Ignimbrites, underplating and mixing with basic melts are indicated by Mg-rich annite–siderophyllite and δ18O, Technische Universität Bergakademie Freiberg (3135)
Published: 2021
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4. Karastic features associated with unconformity surfaces, a case study from the United Arab Emirates

Author: El-Sayed, Mohamed I
Published: 2000
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5. Earth curvature effects on subduction morphology: Modeling subduction in a spherical setting with the fast multipole boundary element method

Author: Roma Tre University, Rome, Italy - Geology Department, UCL - FSA/MECA - Département de mécanique, ETH Zurich, CH-8092, Switzerland - Geophysical Fluid Dynamics, ETH Zurich, CH-8092, Switzerland - Computational Science and Engineering Laboratory, Morra, Gabriele, Chatelain, Philippe, Tackley, Paul, Koumoutsakos, Petros, Roma Tre University, Rome, Italy - Geology Department, UCL - FSA/MECA - Département de mécanique, ETH Zurich, CH-8092, Switzerland - Geophysical Fluid Dynamics, ETH Zurich, CH-8092, Switzerland - Computational Science and Engineering Laboratory, Morra, Gabriele, Chatelain, Philippe, Tackley, Paul, and Koumoutsakos, Petros
Abstract: We present the first application in geodynamics of a (Fast Multipole) Accelerated Boundary Element Method (Accelerated-BEM) for Stokes flow. The approach offers the advantages of a reduced number of computational elements and linear scaling with the problem size. We show that this numerical method can be fruitfully applied for the simulation of several geodynamic systems at the planetary scale in spherical coordinates, and we suggest a general approach for modeling combined mantle convection and plate tectonics. The first part of the paper is devoted to the technical exposition of the new approach, while the second part focuses on the effect played by Earth curvature on the subduction of a very wide oceanic lithosphere (W = 6,000 km and W = 9,000 km), comparing the effects of two different planetary radii (ER = 6,371 km, 2ER = 2 9 6,371 km), corresponding to an ‘‘Earth-like’’ model (ER) and to a ‘‘flat Earth’’ one (2ER). The results show a distinct difference between the two models: while the slab on a ‘‘flat Earth’’ shows a slight undulation, the same subducting plate on the ‘‘Earth-like’’ setting presents a dual behavior characterized by concave curvature at the edges and by a folding with wavelength of the order of magnitude of 1,000 km at the center of the slab.
Published: 2009

6. TEM and AEM constraints on the origin and significance of chlorite-mica stacks in slates: an example from Central Wales, U.K.

Author: Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109-1063, U.S.A., British Geological Survey, Keyworth, Nottingham NG12 5GG, U.K., Geology Department, Birkbeck College, Malet Street, London WC1E 7HX, U.K., Li, Gejing, Peacor, Donald R., Merriman, R.J., Roberts, B., Van der Pluijm, Ben A., Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109-1063, U.S.A., British Geological Survey, Keyworth, Nottingham NG12 5GG, U.K., Geology Department, Birkbeck College, Malet Street, London WC1E 7HX, U.K., Li, Gejing, Peacor, Donald R., Merriman, R.J., Roberts, B., and Van der Pluijm, Ben A.
Abstract: Chlorite-mica stacks (grains of intergrown chlorite and white mica) in a matrix of fine-grained white mica and chlorite have been studied using XRD, SEM, EMPA, TEM and AEM methods. The stacks occur in a weakly cleaved Llandoverian mudstone, central Wales, which has a white mica (illite) crystallinity index of 0.35[deg] [Delta]2[phi] corresponding to the lower anchizone. White mica occurs as packets (100 A to 8 [mu]m thick) interleaved with dominant chlorite packets in stacks, with both apparent coherent interfaces or cross-cutting small angle boundaries with chlorite layers. It is well-crystallized 2M1 polytype with phengitic composition and low paragonite component [Na/(Na + K) 2 crystals surround stacks and occur within chlorite, and white mica is Ti-rich compared to matrix white mica. Fine-grained white mica and chlorite in the matrix have two different orientations: one parallel to hedding and one parallel to cleavage, which is approximately 30-50[deg] to bedding. Matrix white mica is predominantly a 2M1 polytype, but some cleavage-parallel white mica is 3T and some bedding-parallel white mica is 1Ma. It is Na-rich [(Na/(Na + K) ~ 0.14-0.42] and relatively heterogeneous; some discrete paragonite and phengitic muscovite are observed to coexist in the cleavage orientation. Matrix white mica and chlorite each contain less Fe than corresponding white mica and chlorite in stacks. Both matrix and stack chlorite are one-layer polytypes. The data imply that chlorite in the stacks is largely derived from the replacement of volcanogenic biotite and other ferromagnesian minerals (probably via intermediate expandable trioctahedral phyllosilicates). Most intergrowths of chlorite and mica in stacks formed by mica replacement of chlorite and altered biotite along cleavage fissures. Subsequent deformation caused further modification of pre-existing chlorite-mica stacks whereas partial dissolution of stacks and bedding-parallel matrix phyllosilicates resulted in the formation of c
Published: 2006

7. Synthesis, characterization, and dispersion properties of hydroxyapatite prepared by mechanochemical–hydrothermal methods

Author: Chen, Chun-Wei, Oakes, Charles S., ByrappaPresent address: University of Mysore, Kullaiah, Geology, Department of, 21, P. B. No., Mysore-570006, In, Riman, Richard E., Brown, Kelly, TenHuisen, Kevor S., and Janas, Victor F.
Abstract: Thermodynamic modeling was utilized to identify reaction conditions to prepare phase-pure hydroxyapatite particulates HA by mechanochemical–hydrothermal M–H methods using CaOH2and NH42HPO4as precursors. The resulting HA powders were characterized by X-ray diffraction, infra-red spectroscopy, thermogravimetry, and transmission electron microscopy, nitrogen adsorption and dynamic light scattering methods. Choosing reaction conditions in the 99 yield region of the CaO–P2O5–NH4OH–H2O phase-pure equilibrium system, nearly stoichiometric and nanostructured HA powders were prepared at room temperature in as little as 1 h. The minimum time to obtain phase-pure HA was 8 h from the conventional attrition mill. As-prepared powders were found to be highly agglomerated with a mass-weighted mean diameter of 2.6 µm in deionized water and average agglomeration number AAN as high as 4.5 × 106. Dispersion studies revealed that the appropriate use of dispersants could reduce the mass-weighted mean diameter and AAN. In the presence of sodium polyacrylate, the mass-weighted mean diameter and AAN were 217 nm and 1600, respectively.
Published: 2004
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8. Revised geology and mineral potential of the Colville Indian Reservation, Washington, 1984.

Author: Colville Confederated Tribes Geology Department. and Colville Confederated Tribes Geology Department.
Abstract: The recent comprehensive appraisal has added substantially to the knowledge of the area's geology and mineral deposits, indicating several potential exploration targets and suggesting that many important deposits remain to be discovered. Significant hypotheses are as follows: the Colville batholith is compositionally zoned with the Sanpoil Volanics derived from its deep interior; it was the source of all the known mineral deposits; fractures produced by crustal extension controlled the emplacement of the most important deposits and the porphyry dykes; and emplacement of the dykes interrupted metal-concentrating processes within the batholith, ending the main period of mineral deposition. Detailed recommendations are made for future exploration. Many of the smaller vein deposits would be profitable to mine if a custon mill were located in the area to reduce bulk transport costs. The report concludes with a selected bibliography., The recent comprehensive appraisal has added substantially to the knowledge of the area's geology and mineral deposits, indicating several potential exploration targets and suggesting that many important deposits remain to be discovered. Significant hypotheses are as follows: the Colville batholith is compositionally zoned with the Sanpoil Volanics derived from its deep interior; it was the source of all the known mineral deposits; fractures produced by crustal extension controlled the emplacement of the most important deposits and the porphyry dykes; and emplacement of the dykes interrupted metal-concentrating processes within the batholith, ending the main period of mineral deposition. Detailed recommendations are made for future exploration. Many of the smaller vein deposits would be profitable to mine if a custon mill were located in the area to reduce bulk transport costs. The report concludes with a selected bibliography.

9. Measurements of Saharan dust aerosols over the Eastern Mediterranean using elastic backscatter-Raman lidar, spectrophotometric and satellite observations in the frame of the EARLINET project

Author: Department of Physics ; Department of Physics, Laboratory of Atmospheric Physics ; Laboratory of Atmospheric Physics, Department of Geology ; Department of Geology, Euro-Mediterranean Center on Insular Coastal Dynamics ; Euro-Mediterranean Center on Insular Coastal Dynamics, Papayannis, A., Balis, D., Amiridis, V., Chourdakis, G., Tsaknakis, G., Zerefos, C., Castanho, A. D. A., Nickovic, S., Kazadzis, S., Grabowski, J., Department of Physics ; Department of Physics, Laboratory of Atmospheric Physics ; Laboratory of Atmospheric Physics, Department of Geology ; Department of Geology, Euro-Mediterranean Center on Insular Coastal Dynamics ; Euro-Mediterranean Center on Insular Coastal Dynamics, Papayannis, A., Balis, D., Amiridis, V., Chourdakis, G., Tsaknakis, G., Zerefos, C., Castanho, A. D. A., Nickovic, S., Kazadzis, S., and Grabowski, J.
Abstract: International audience, We report on the vertical distributions of Saharan dust aerosols over the N.E. Mediterranean region, which were obtained during a typical dust outbreak on August 2000, by two lidar systems located in Athens and Thessaloniki, Greece, in the frame of the European EARLINET project. MODIS and ground sun spectrophotometric data, as well as air-mass backward trajectories confirmed the existence of Saharan dust in the case examined, which was also successfully forecasted by the DREAM dust model. The lidar data analysis for the period 2000?2002 made possible, for the first time, an estimation of the vertical extent of free tropospheric dust layers (mean values of the aerosol backscatter and extinction coefficients and the extinction-to-backscatter ratio (lidar ratio, LR) at 355 nm), as well as a seasonal distribution of Saharan dust outbreaks over Greece, under cloud-free conditions. A mean value of the lidar ratio at 355 nm was obtained over Athens (52.81±1.02 sr) and over Thessaloniki (44.19±1.72 sr) during the Saharan dust outbreaks. The corresponding aerosol optical thickness (AOT) at 355 nm, in the altitude range 0?5 km, was 0.69±0.12 and 0.65±0.10 for Athens and Thessaloniki, respectively (within the dust layer the AOT was 0.23 and 0.21, respectively). Air-mass back-trajectory analysis performed in the period 2000?2002 for all Saharan dust outbreaks over the N. E. Mediterranean indicated the main pathways followed by the dust aerosols.

10. A proto-monsoonal climate in the late Eocene of Southeast Asia: Evidence from a sedimentary record in central Myanmar

Author: Huasheng Huang, Robert J. Morley, Alexis Licht, Guillaume Dupont-Nivet, Daniel Pérez-Pinedo, Jan Westerweel, Zaw Win, Day Wa Aung, Eko Budi Lelono, Galina N. Aleksandrova, Ramesh K. Saxena, Carina Hoorn, Institute for Biodiversity and Ecosystem Dynamics (IBED), University of London [London], 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), University of Potsdam = Universität Potsdam, Géosciences Rennes (GR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), University of Amsterdam [Amsterdam] (UvA), Memorial University of Newfoundland = Université Memorial de Terre-Neuve [St. John's, Canada] (MUN), Geology Department, Shwe Bo University, Sagaing Region, Geology Department, University of Yangon, Pyay Rd, Yangon, Badan Geologi, Geological Institute of the Russian Academy of Sciences, Russian Academy of Sciences [Moscow] (RAS), Birbal Sahni Institute of Palaeosciences, China Scholarship Council (CSC grant 201604910677), University of Amsterdam, ANR-19-ERC7-0007,DISPERSAL,Un contrôle tectonique ou climatique sur la dispersion des premiers primates ? Investigation de la dynamique des espèces invasives au cours des temps géologiques(2019), European Project: 649081,H2020,ERC-2014-CoG,MAGIC(2015), Ecosystem and Landscape Dynamics (IBED, FNWI), and IBED (FNWI)
Subjects: Diversity, Monsoon, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, Bioclimatic analysis, [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, Sequence biostratigraphy, General Earth and Planetary Sciences, Palynology, Southeast Asia
Abstract: International audience; The Burma Terrane has yielded some of the earliest pieces of evidence for monsoonal rainfall in the Bay of Bengal. However, Burmese ecosystems and their potential monsoonal imprint remain poorly studied. This study focuses on the late Eocene Yaw Formation (23° N) in central Myanmar, which was located near the equator (c. 5° N) during the Eocene. We quantitatively assessed the past vegetation, climate, and depositional environments with sporomorph diagrams, bioclimatic analysis, and sequence biostratigraphy. We calculated the palynological diversity and drew inferences with rarefaction analysis by comparing with four other middle to late Eocene tropical palynofloras. Palynological results highlight a high floristic diversity for the palynoflora throughout the section formed by six pollen zones characterized by different vegetation. They indicate that lowland evergreen forests and swamps dominated in the Eocene Burmese deltaic plains while terra firma areas were occupied by seasonal evergreen, seasonally dry, and deciduous forests. This vegetation pattern is typical to what is found around the Bay of Bengal today and supports a monsoon-like climate at the time of the Yaw Formation. Bioclimatic analysis further suggests that in the late Eocene, the Yaw Formation was more seasonal, drier, and cooler compared to modern-day climate at similar near-equatorial latitude. More seasonal and drier conditions can be explained by a well-marked seasonal migration of the Intertropical Convergence Zone (ITCZ), driver of proto-monsoonal rainfall. Cooler temperatures in the late Eocene of central Myanmar may be due to the lack of adequate modern analogues for the Eocene monsoonal climate, while those found at other three Eocene Asian paleobotanical sites (India and South China) may be caused by the effect of canopy evapotranspirational cooling. Our data suggest that paleoenvironmental change including two transgressive-regressive depositional sequences is controlled by global sea level change, which may be driven by climate change and tectonics. The high diversity of the Yaw Formation palynoflora, despite well-marked seasonality, is explained by its cross-roads location for plant dispersals between India and Asia.
Published: 2023
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11. Dynamics of pedogenic carbonate growth in the tropical domain of Myanmar

Author: A. Licht, J. Kelson, S. Bergel, A. Schauer, S. V. Petersen, A. Capirala, K. W. Huntington, G. Dupont‐Nivet, Zaw Win, Day Wa Aung, 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), University of Washington [Seattle], University of Michigan [Ann Arbor], University of Michigan System, Géosciences Rennes (GR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Geology Department, Shwe Bo University, Sagaing Region, Geology Department, University of Yangon, Pyay Rd, Yangon, University of Washington, European Project: 649081,H2020,ERC-2014-CoG,MAGIC(2015), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), and Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Geophysics, Geochemistry and Petrology, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences
Abstract: International audience; Pedogenic carbonate is widespread at mid latitudes where warm and dry conditions favor soil carbonate growth from spring to fall. The mechanisms and timing of pedogenic carbonate formation are more ambiguous in the tropical domain, where long periods of soil water saturation and high soil respiration enhance calcite dissolution. This paper provides stable carbon, oxygen and clumped isotope values from Quaternary and Miocene pedogenic carbonates in the tropical domain of Myanmar, in areas characterized by warm (>18°C) winters and annual rainfall up to 1700 mm. We show that carbonate growth in Myanmar is delayed to the driest and coldest months of the year by sustained monsoonal rainfall from mid spring to late fall. The range of isotopic variability in Quaternary pedogenic carbonates can be solely explained by temporal changes of carbonate growth within the dry season, from winter to early spring. We propose that high soil moisture year-round in the tropical domain narrows carbonate growth to the driest months and makes it particularly sensitive to the seasonal distribution of rainfall. This sensitivity is also enabled by high winter temperatures, allowing carbonate growth to occur outside the warmest months of the year. This high sensitivity is expected to be more prominent in the geological record during times with higher temperatures and greater expansion of the tropical realm. Clumped isotope temperatures, δ13C and δ18O values of tropical pedogenic carbonates are impacted by changes of both rainfall seasonality and surface temperatures; this sensitivity can potentially be used to track past tropical rainfall distribution.
Published: 2022
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12. Fossil wood: a key to understand paleoenvironmental and biogeographic evolutions in South and Southeast Asia

Author: Nicolas Gentis, Anais Boura, Dario De Franceschi, Alexis Licht, Zaw Win, Day Wa Aung, Centre de Recherche en Paléontologie - Paris (CR2P), Muséum national d'Histoire naturelle (MNHN)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Sorbonne Université (SU), 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), Geology Department, Shwe Bo University, Sagaing Region, and Geology Department, University of Yangon, Pyay Rd, Yangon
Subjects: [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology
Abstract: International audience; Monsoons are the defining climatic phenomenon of South and Southeast Asia. Monsoons are primarily controlled by topographic effects caused by Asian uplifts such as the Tibetan Plateau, the Himalayas or the Indo-Burman Ranges; their establishment during the Cenozoic and their evolution are yet not fully understood. Myanmar stands along the Bengal Bay, in the core engine of the South Asian monsoon, and is thus a relevant area of investigation. The country is separated today from India by the Indo-Burman Ranges. Fossil wood specimens from Myanmar offers the opportunity to follow the local evolution of the ecosystems and the biogeographical evolution of some taxa. A first comparison between the Pondaung (late Middle Eocene) and Natma (late Lower Miocene to early Middle Miocene) Formations allows us to identify long-term floristic changes. Eocene forest assemblages present taxa affiliated with modern analogues of dry dipterocarp forests (such as Sal, Shorea robusta C.F. Gaertn.). By contrast, Miocene forests are more analogous to modern tropical rainforests dominated by dipterocarps adapted to wetter conditions. These changes could first indicate a stronger monsoon regime during the Miocene than the Eocene, potentially due to regional uplift. From a biogeographical standpoint, these results support an emergence of the Dipterocarpaceae family in a dry seasonal climate, followed by a diversification and spreading toward everwet tropical zones. We also identify species similar to those of modern mangroves in both formations, confirming the continuous presence of this ecosystem in South Asia since at least since the middle Eocene. The expansion of the study to other geological units of Myanmar dating from the Paleocene, the Eocene, the Oligocene and the Miocene offers the possibility to draw up a more global overview of the climatic and biogeographic evolution of South Asia.
Published: 2021

13. Fossil woods from the middle Miocene of Myanmar: implications for the evolution of Dipterocarpaceae

Author: Nicolas Gentis, Alexis Licht, Anaïs Boura, Za Win, Day Wa Aung, Guillaume Dupont-Nivet, Muséum national d'Histoire naturelle (MNHN), 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), Centre de Recherche en Paléontologie - Paris (CR2P), Muséum national d'Histoire naturelle (MNHN)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Sorbonne Université (SU), Geology Department, Shwe Bo University, Sagaing Region, and Geology Department, University of Yangon, Pyay Rd, Yangon
Subjects: [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology
Abstract: International audience; The paleobotanical record of Myanmar is poorly documented despite its importance for understanding the evolution of Asian rainforests, often dominated today by Dipterocarpaceae. The middle Eocene of Myanmar has yielded some of the earliest Dipterocarpaceae of the paleobotanical record, associated with seasonally dry forests that are today common in monsoonal areas of India. Here, we describe 17 species of fossil woods (including 4 new species) collected in the middle Miocene Natma Formation, central Myanmar. These species share affinities with modern Fabaceae, Dipterocarpaceae, Burseraceae, Moraceae and Cupressaceae. They include a great variety of fossil dipterocarps (7 species) similar to the one found in modern rainforests of peninsular Southeast Asia. The presence of fossil dipterocarp species typical of wet evergreen forests contrasts with Burmese Eocene dry dipterocarp assemblages and indicates wetter conditions in the Miocene. Our paleoenvironmental reconstructions support a late Paleogene adaptation of dipterocarps to everwet ecosystems, as suggested by previous physiological and biogeographic studies.
Published: 2020

14. The Pre‐Obduction to Post‐Obduction Evolution of the Sivas Ophiolite (Turkey) and Implications for the Precollisional History of Eastern Anatolia

Author: Kaan Sevki Kavak, Jean-Paul Callot, Geoffroy Mohn, Jean-Claude Ringenbach, Alexey Ulianov, Etienne Legeay, Laboratoire des Fluides Complexes et leurs Réservoirs (LFCR), Centre National de la Recherche Scientifique (CNRS)-Université de Pau et des Pays de l'Adour (UPPA)-TOTAL FINA ELF, Centre scientifique et Technique Jean Feger (CSTJF), TOTAL FINA ELF, Université de Cergy Pontoise (UCP), Université Paris-Seine, Institute of Mineralogy and Geochemistry, Université de Lausanne (UNIL), Department of Geological Engineering [Sivas, Turkey], Cumhuriyet University [Sivas, Turkey], and Legeay, E., E2S UPPA CNRS/TOTAL/University of Pau and Pays Adour, Laboratoire Des Fluides Complexes Et Leurs Reservoirs-IPRA, UMR5150, Pau, France, Structural Geology Department, Total SA, CSTJF, Pau, France -- Mohn, G., Géosciences Environnement Cergy, Université de Cergy-Pontoise, Cergy-Pontoise, France -- Callot, J.-P., E2S UPPA CNRS/TOTAL/University of Pau and Pays Adour, Laboratoire Des Fluides Complexes Et Leurs Reservoirs-IPRA, UMR5150, Pau, France -- Ringenbach, J.-C., Structural Geology Department, Total SA, CSTJF, Pau, France -- Ulianov, A., Institut des Sciences de la Terre, Université de Lausanne, Lausanne, Switzerland -- Kavak, K.S., Department of Geological Engineering, Sivas Cumhuriyet University, Sivas, Turkey
Subjects: eastern Tauride, 010504 meteorology & atmospheric sciences, Geochemistry, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, 15. Life on land, 010502 geochemistry & geophysics, Ophiolite, 01 natural sciences, ophiolite belt, Obduction, supraophiolite basin, Sivas basin, Geophysics, Geochemistry and Petrology, obduction, Sivas ophiolite, Geology, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: The Anatolian block preserves remnants of Tethyan oceanic basins consumed by north dipping subduction zones until the Late Cretaceous prior to Paleogene collision. The Sivas Basin, which belongs to the Maastrichtian to Cenozoic Central Anatolian basins, is located in a key position limited to the north and the south by respectively the Pontides and Tauride ophiolitic bodies and to the west by the Kırşehir block. This study focuses on the southern margin of the Sivas Basin, where an obducted ophiolite is capped by Maastrichtian-Paleocene sediments. We present new field observations, with U-Pb zircon dating on magmatic rocks and geochemical analyses to (1) unravel the pre-obduction nature and origin of the ophiolitic basement and (2) describe the post-obduction tectonosedimentary evolution. The pre-obduction evolution shows that (i) the Sivas ophiolite is characterized by serpentinized peridotites, with minor magmatic intrusions, (ii) the top of the serpentinized mantle is characterized by a cataclastic deformation with ophicalcites interpreted as an extensional detachment fault, (iii) the U-Pb zircon dating of two magmatic intrusions yield age of 91.49 ± 0.8 Ma and 72.7 ± 0.5 Ma, and (iv) petrological and geochemical data show that the magmatic intrusions were affected by hydrothermal metamorphism. These data suggest that the Sivas ophiolite may have recorded forearc hyperextension in frame of a Late Cretaceous suprasubduction zone. The post-obduction evolution is characterized by the deposition of a Maastrichtian-Paleocene carbonate platform on the ophiolite, followed by clastic sediments containing reworked ophiolitic and Tauride Mesozoic clasts. ©2019. American Geophysical Union. All Rights Reserved., Total Université de Lausanne Universitat de Barcelona, This work results from a research agreement between TOTAL and University of Pau and Pays Adour. Sivas C?mhuriyet University, most particularly H. Temiz, is thanked for support and collaboration during the fieldwork. Mary Ford (University of Lorraine) is warmly thanked for comments. We thank Josep-Serra Kiel (University of Barcelona) and J?r?mie Gaillot (Total, CSTJF) for identifying Maastrichtian-Paleocene microfossil and interesting discussions on Late Cretaceous evolution of the basin. Othmar M?ntener (University of Lausanne), Jaume Verg?s (University of Barcelona) are thanked for fruitful discussions. We also acknowledge the field party: C. Kergaravat, A. Pichat, C. Ribes, C. Bonnel, and B. Rouby (University of Pau). Benoit Petri is thanked for his help for the use of Isoplot software. The authors acknowledge the details reviews by M. Maffione, A. Okay, D. van Hinsbergen, and two anonymous reviewers. Eventually, the Associate Editor F. Rossetti is thanked for his comments as well as the Editor Laurent Jolivet for his advice. Geochemistry and U-Pb dating are presented in their entirety in both manuscript and in the supporting information. Tectonosedimentary data can be obtained from cited references.
Published: 2019
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15. Metal anomaly prospection at cerrado. Example for the use of si-phytoliths at Riacho dos Machado region, Minas Gerais, Brazil

Author: Fernandes-Horn, Heloiza Márcia, Horn, Adolf Heinrich, Sampaio, Regynaldo Arruda, Rodrigues, Marcio Neves, Duarte, Luana, Bilal, Essaïd, Baggio-Filho, Hernando, Claret Torres, Isabela, Federal University of Minas Gerais (UFMG), Instituto de Ciências Agrárias, Universidade Federal de Minas Gerais, Environmental Geochemistry Laboratory, Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), Geology Department Geoscience Institute, École des Mines de Saint-Étienne (Mines Saint-Étienne MSE), Institut Mines-Télécom [Paris] (IMT), Université de Lyon, Centre National de la Recherche Scientifique (CNRS), Environnement Ville Société (EVS), Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-École nationale supérieure d'architecture de Lyon (ENSAL)-École des Mines de Saint-Étienne (Mines Saint-Étienne MSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-École Nationale des Travaux Publics de l'État (ENTPE)-Université Jean Monnet [Saint-Étienne] (UJM)-Université Jean Moulin - Lyon 3 (UJML), Université de Lyon-Université Lumière - Lyon 2 (UL2)-École normale supérieure - Lyon (ENS Lyon), Centre Sciences des Processus Industriels et Naturels (SPIN-ENSMSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Département Procédés pour l'Environnement et Géoressources (PEG-ENSMSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-École des Mines de Saint-Étienne (Mines Saint-Étienne MSE), Universidade Federal dos Vales do Jequitinhonha e Mucuri = Federal University of Jequitinhonha and Mucuri Vallays (UFJMV), Campus Juscelino Kubitschek, Geography Department, Geoscience Institute, Federal University of Minas Gerais - Instituto de Ciências Agrárias-Campus Avançado, Federal University of Minas Gerais - Environmental Geochemistry Laboratory Geology Department, Geoscience Institute, Federal University of Jequitinhonha and Mucuri Valleys - Campus Juscelino Kubitschek, Federal University of Minas Gerais - Geography Department, Geoscience Institute, Universidade Federal de Minas Gerais = Federal University of Minas Gerais [Belo Horizonte, Brazil] (UFMG), Environnement, Ville, Société (EVS), École normale supérieure de Lyon (ENS de Lyon)-École des Mines de Saint-Étienne (Mines Saint-Étienne MSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université Lumière - Lyon 2 (UL2)-Université Jean Moulin - Lyon 3 (UJML), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet - Saint-Étienne (UJM)-École Nationale des Travaux Publics de l'État (ENTPE)-École nationale supérieure d'architecture de Lyon (ENSAL)-Centre National de la Recherche Scientifique (CNRS)
Subjects: QE1-996.5, Chemistry, prospecção de metais, plantas, Geology, Si-Fitólitos, Cerrado, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Plants, Si-Phytoliths, Savannah, QD1-999, Metal prospection
Abstract: International audience; The target area of this work is a heavy metal anomaly in the surroundings of a gold mine and a lead mining complex. This work investigated the distribution of selected heavy elements in soil samples and Si-Phytoliths from plants. The aim was to verify if metal contents are indicative for metal anomalies in the soil. Plants and soil samples were collected in profiles over granitic-gneissic rocks, which form the basement, in tectonized contact with the overlaying sedimentary units belonging to the Riacho dos Machados Group, part of the Espinhaço Super Group. The whole rock substrate is covered by lateritic to arenitic soils with different exposure depths. Metal-rich fluid invaded these units, forming metal anomalies culming in Zn-Pb-Au deposits, like that of Salobre-Porteirinha. After appropriate preparation, the samples were, analyzed by ICP-OES (Si-Phytoliths) and FRX (soil). Anomalies in the investigated profile are indicated by high metal contents in the Si-Phytoliths of the selected species. Using different species the metal concentration in different depths can be determined in a simple and easy way. The Si-Phytolith concentrations seem to reproduce better the rock metal anomalies than the soil samples.; O alvo deste trabalho é uma anomalia de metais pesados nos arredores de uma mina de ouro em uma mineração de chumbo. Este estudo investigou a distribuição dos elementos pesados selecionados em amostras de solo e em Si-Fitólitos de plantas. O objetivo foi verificar se o conteúdo de metais nos Si-Fitólitos é indicativo para anomalias destes metal no solo ou substrato. Plantas e amostras de solo foram coletadas em perfis de solos sobre rochas gnáissicograníticas, que formam o embasamento e que estão em contato tectônico com as unidades sedimentares superiores, pertencentes ao Grupo Riacho dos Machados, parte do Supergrupo Espinhaço. O embasamento é coberto por solos lateríticos a areniticos, com profundidades de exposição diferente. Fluido rico em metal invadiu estas unidades, formando anomalias de metais que chegaram a depósitos econômicos de Pb-Zn-Au, como o de Salobre-Porteirinha e Riacho dos Machados. Após a preparação adequada, as amostras foram, analisadas por ICP-OES (amostras de Si-Phytoliths) e FRX (amostras de solo). Anomalias no perfil investigado são indicadas pelo alto conteúdo de metal na Si-Phytoliths das espécies selecionadas. A concentração de metal em diferentes profundidades usando diferentes espécies pode ser simples e fácilmente executada. As concentrações de Si-Phytolith parecem reproduzir melhor as anomalias metálicas do substrato de rocha do que as amostras de solo.
Published: 2018
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16. The high-pressure phase of boron, γ-B28: Disputes and conclusions of 5 years after discovery

Author: Oleksandr O. Kurakevych, Carlo Gatti, Artem R. Oganov, Vladimir L. Solozhenko, Y. Le Godec, Department of Geosciences [Stony Brook], Stony Brook University [The State University of New York] ( SBU ), Department of Physics and Astronomy [Stony Brook], New York Center for Computational Sciences ( NYCCS ), Brookhaven National Laboratory-Stony Brook University [The State University of New York] ( SBU ), Geology Department, Moscow State University, Geology Department, Laboratoire des Sciences des Procédés et des Matériaux ( LSPM ), Université Paris 13 ( UP13 ) -Université Sorbonne Paris Cité ( USPC ) -Institut Galilée-Centre National de la Recherche Scientifique ( CNRS ), CNR ISTM Istituto di Scienze e Tecnologie Molecolari, CNR ISTM, Institut de minéralogie, de physique des matériaux et de cosmochimie ( IMPMC ), 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 ), Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY), New York Center for Computational Sciences (NYCCS), Brookhaven National Laboratory [Upton, NY] (BNL), U.S. Department of Energy [Washington] (DOE)-UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE)-UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), Laboratoire des Sciences des Procédés et des Matériaux (LSPM), Centre National de la Recherche Scientifique (CNRS)-Université Sorbonne Paris Cité (USPC)-Institut Galilée-Université Paris 13 (UP13), 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), UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE), Université Paris 13 (UP13)-Institut Galilée-Université Sorbonne Paris Cité (USPC)-Centre National de la Recherche Scientifique (CNRS), CNR ISTM Istituto di Scienze e Tecnologie Molecolar, Institut de minéralogie et de physique des milieux condensés (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), and Université Pierre et Marie Curie - Paris 6 (UPMC)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Equation of state, Materials science, chemistry.chemical_element, Thermodynamics, 02 engineering and technology, high pressure phase, 01 natural sciences, Inorganic Chemistry, Physics - Chemical Physics, Phase (matter), 0103 physical sciences, General Materials Science, Isostructural, 010306 general physics, Boron, Phase diagram, high-pressure phase, Condensed Matter - Materials Science, high, [ PHYS.COND.CM-GEN ] Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], γ B28, 021001 nanoscience & nanotechnology, Hybrid functional, pressure phase, chemistry, Chemical bond, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], gamma-B28, Density functional theory, boron, 0210 nano-technology
Abstract: International audience; --The γ B28 phase is a recently established high pressure phase of boron. Its structure consists of icosahedral B12 clusters and B2 dumbbells in a NaCl type arrangement (B2)δ+(B12)δ- and displays a sig nificant charge transfer δ ~ 0.5-0.6. The discovery of this phase proved to be essential for the understand ing and construction of the phase diagram of boron. It was first experimentally obtained as a pure boron allotrope in early 2004 and its structure was discovered in 2006. This paper reviews recent results and con tentious issues related to the equation of state, hardness, putative isostructural phase transformation at ~40 GPa, and debates on the nature of chemical bonding in this phase. Our analysis confirms that (a) calcula tions based on density functional theory give an accurate description of its equation of state, (b) the reported isostructural phase transformation in γ B28 is an artifact, (c) the best estimate of hardness of this phase is 50 GPa, (d) chemical bonding in this phase has a significant degree of ionicity. Apart from pre senting an overview of the previous results within a consistent view grounded in experiment, thermody namics and quantum mechanics, we present new results on Bader charges in γ B28 using different levels of quantum mechanical theory (GGA, exact exchange, and HSE06 hybrid functional), and show that the earlier conclusion about a significant degree of a partial ionicity in this phase is very robust. An additional insight into the nature of the partial ionicity is obtained from a number of boron structures theoretically constructed in this work.
Published: 2011
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17. Possible use of Si-Phytoliths in metal anomaly prospection. Example from Riacho dos Machado region, Cerrado, Minas Gerais, Brazil

Author: Heloiza Márcia Fernandes-horn, Adolf Heinrich Horn, Regynaldo Arruda Sampaio, Hernando Baggio, Márcio Neves Rodrigues, Luana Duarte, Izabelle de Paula Sousa, Adelaide Cristielle Barbosa da Silva, Essaid Bilal, Agronomic Institute (IGA), Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), Instituto de Geociências [Minas Gerais] (IG - UFMG), Universidade Federal de Minas Gerais, Environmental Geochemistry Laboratory, Geology Department Geoscience Institute, Instituto de Ciências Agrárias, Universidade Federal dos Vales do Jequitinhonha e Mucuri = Federal University of Jequitinhonha and Mucuri Vallays (UFJMV), Centre Sciences des Processus Industriels et Naturels (SPIN-ENSMSE), École des Mines de Saint-Étienne (Mines Saint-Étienne MSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Environnement, Ville, Société (EVS), École normale supérieure de Lyon (ENS de Lyon)-École des Mines de Saint-Étienne (Mines Saint-Étienne MSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université Lumière - Lyon 2 (UL2)-Université Jean Moulin - Lyon 3 (UJML), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet - Saint-Étienne (UJM)-École Nationale des Travaux Publics de l'État (ENTPE)-École nationale supérieure d'architecture de Lyon (ENSAL)-Centre National de la Recherche Scientifique (CNRS), Département GéoSciences et Environnement (GSE-ENSMSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-SPIN, IGA-Agronomic Institute, Post-Graduation (Msc) in Agronomy-UFMG-Federal University of Minas Gerais, Environmental Geochemistry Laboratory-Geology Department Geoscience Institute-UFMG-Federal University of Minas Gerais, ICA-UFMG--Federal University of Minas Gerais, UFVJM-Federal University of Jequitinhonha and Mucuri Valleys, Environnement Ville Société (EVS), Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-École nationale supérieure d'architecture de Lyon (ENSAL)-École des Mines de Saint-Étienne (Mines Saint-Étienne MSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-École Nationale des Travaux Publics de l'État (ENTPE)-Université Jean Monnet [Saint-Étienne] (UJM)-Université Jean Moulin - Lyon 3 (UJML), and Université de Lyon-Université Lumière - Lyon 2 (UL2)-École normale supérieure - Lyon (ENS Lyon)
Subjects: plants, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDE]Environmental Sciences, metals, Metais, Cerrado, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, prospection, Si-Phytoliths, Plantas
Abstract: This work investigates the distribution of selected heavy elements in soil samples and Si-Phytoliths from plants. The aim is to verify if metal contents are indicative for metal anomalies in the soil. Samples were collected in profiles near the Riacho dos Machados Goldmine. Granitic-gneissic rocks, in tectonized contact with the overlaying rocks, form the basis of the investigated region, which belongs to the Rio dos Machados Group of the Espinhaço Super Group. The whole rock substrate is covered by lateritic to arenitic soils with different exposure depths. Metal-rich fluid invaded this unit, forming metal anomalies, forming Zn-Pb-Au deposits, like that of Salobre-Porteirinha. After appropriate preparation, the samples were analyzed by ICP-OES (Si-Phytoliths) and XRF (soil). Anomalies in the investigated profile are indicated by high metal contents in the Si-Phytoliths of the selected species. Using different species, the metal concentration at different depths can be determined. Este trabalho investiga a distribuição de elementos pesados selecionados em amostras de solo e Si-Fitólitos de plantas. O objetivo é verificar se os teores de metais são indicativos de anomalias metálicas no solo. As amostras foram coletadas em perfis próximos à Mina Riacho dos Machados. Rochas granítico-gnáissicas, em contato tectonizado com as rochas sobrepostas, formam a base da região investigada, que pertence ao Grupo Rio dos Machados do Super Grupo Espinhaço. Todo o substrato rochoso é coberto por solos lateríticos a areníticos com diferentes profundidades de exposição. Fluido rico em metais invadiu esta unidade, formando anomalias metálicas, formando depósitos de Zn-Pb-Au, como o de Salobre-Porteirinha. Após o devido preparo, as amostras foram analisadas por ICP-OES (Si-Phytoliths) e XRF (solo). Anomalias no perfil investigado são indicadas por altos teores de metais nos Si-Fitólitos das espécies selecionadas. Usando diferentes espécies, a concentração de metal em diferentes profundidades pode ser determinada.
Published: 2016

18. Fine-scale sedimentary architecture of the upper part of the Jezero western delta front

Author: Gupta, Sanjeev, Bell III, J.F., Caravaca, Gwénaël, Mangold, Nicolas, Stack‐Morgan, Katie, Kanine, Oak, Tate, Christian, Tice, Michael M., Williams, Amy, Russell, Patrick, Núñez, Jorge, Dromart, Gilles, Williams, R, Le Mouélic, Stéphane, Barnes, Robert, Annex, Andrew, Paar, Gerhard, Holm-Alwmark, Sanna, Rice, Melissa S., Rice, James, Horgan, Briony, Grotzinger, John, Maki, Justin, Hickman Lewis, Keyron, Kah, Lindah, Shuster, David L., Simon, Justin I., Minitti, Michelle, Siebach, Kirsten, Gasnault, Olivier, Wiens, Roger, Maurice, Sylvestre, Farley, Kenneth A., Department of Earth Science and Engineering [Imperial College London], Imperial College London, Arizona State University [Tempe] (ASU), Institut de recherche en astrophysique et planétologie (IRAP), 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), 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)-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), Laboratoire de Planétologie et Géosciences [UMR_C 6112] (LPG), Université d'Angers (UA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST), Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Division of Geological and Planetary Sciences [Pasadena], California Institute of Technology (CALTECH), Cornell University [New York], Texas A&M University [College Station], Department of Geological Sciences [Gainesville] (UF|Geological), University of Florida [Gainesville] (UF), Department of Earth, Planetary and Space Sciences [Los Angeles] (EPSS), University of California [Los Angeles] (UCLA), University of California (UC)-University of California (UC), Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), 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), Planetary Science Institute [Tucson] (PSI), Joanneum Research, University of Copenhagen = Københavns Universitet (UCPH), Geology Department, Western Washington University, Western Washington University (WWU), School of Earth and Space Exploration [Tempe] (SESE), Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, The Natural History Museum [London] (NHM), The University of Tennessee [Knoxville], Berkeley Geochronology Center (BGC), NASA Johnson Space Center (JSC), NASA, Planetary Geosciences Institute [Knoxville], Department of Earth and Planetary Sciences [Knoxville], The University of Tennessee [Knoxville]-The University of Tennessee [Knoxville], Rice University [Houston], and Lunar and Planetary Institute
Subjects: Jezero crater, delta, [SDU.STU.PL]Sciences of the Universe [physics]/Earth Sciences/Planetology, [SDU]Sciences of the Universe [physics], Mars 2020, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Mars, sedimentology
Abstract: International audience; Orbital and rover observations of relict geomorphic features and stratigraphic architectures indicate Mars once had a warmer, wetter climate. Constraining the character, relative timing and persistence of ancient aqueous activity on Mars is possible through detailed interrogation of the stratal geometry of aqueously deposited sedimentary bodies. Such analyses inform interpretations of Martian climate evolution, potential habitability, and search strategies for rocks that might contain potential biosignatures. NASA’s Mars 2020 Perseverance rover mission is seeking signs of ancient life in Jezero crater and is collecting a cache of Martian rock and soil samples for planned return to Earth by a future mission.A prominent sedimentary fan deposit at the western margin of Jezero crater has been interpreted to be a riverdelta that built into an ancient lake basin during the Late Noachian-Early Hesperian epochs on Mars (~3.6-3.8Ga) [1, 2]. The Perseverance rover landed on 18 February 2021 ~2.2 km from the western fan. In March-April 2022, the rover conducted a rapid traverse along the eastern and southeastern side of Jezero fan onlyobtaining a few remote sensing observations along the way. In April 2022, the rover arrived at the base of theancient delta in the Three Forks region of the crater floor adjacent to the delta front (Fig. 1). During the ‘rapidtraverse’ and the exploration of two sections at the delta front - Cape Nukshak and Hawksbill Gap –Perseverance obtained striking images from the Mastcam-Z and SuperCam’s Remote Micro-Imagerinstruments of the stratigraphy exposed stratigraphically higher up in the fan’s erosional front [3]. Images providenew views of the stratigraphy exposed in the erosional front of the western Jezero delta; in particular, showingsections of the delta previously not visible from long distance observations and at much higher resolution.Here, we report its stratigraphy and sedimentology, which provide new constraints on the nature of the fandeposits, and therefore paleoenvironmental implications.
Published: 2023

19. Fine-Scale Sedimentary Architecture of the Jezero Western Delta Front

Author: Gupta, Sanjeev, Bell, Jim F., Caravaca, Gwénaël, Kanine, Oak, Mangold, Nicolas, Stack, Kathryn, Tate, Christian, Tice, Michael M., Williams, Amy, Russell, Patrick, Núñez, Jorge, Dromart, Gilles, Williams, Rebecca M. E., Le Mouélic, Stéphane, Barnes, Robert, Annex, Andrew, Paar, Gerhard, Holm-Alwmark, Sanna, Rice, Melissa S., Rice, James, Horgan, Briony, Grotzinger, John, Maki, Justin, Hickman-Lewis, Keyron, Kah, Linda, Shuster, David L., Simon, Justin I., Minitti, Michelle, Siebach, Kirsten, Gasnault, Olivier, Wiens, Roger, Maurice, Sylvestre, Farley, Kenneth A., Department of Earth Science and Engineering [Imperial College London], Imperial College London, Arizona State University [Tempe] (ASU), Institut de recherche en astrophysique et planétologie (IRAP), 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), 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)-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), Division of Geological and Planetary Sciences [Pasadena], California Institute of Technology (CALTECH), Laboratoire de Planétologie et Géosciences [UMR_C 6112] (LPG), Université d'Angers (UA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST), Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Cornell University [New York], Texas A&M University [College Station], Department of Geological Sciences [Gainesville] (UF|Geological), University of Florida [Gainesville] (UF), Department of Earth, Planetary and Space Sciences [Los Angeles] (EPSS), University of California [Los Angeles] (UCLA), University of California (UC)-University of California (UC), Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), 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), Planetary Science Institute [Tucson] (PSI), Joanneum Research, University of Copenhagen = Københavns Universitet (UCPH), Geology Department, Western Washington University, Western Washington University (WWU), School of Earth and Space Exploration [Tempe] (SESE), Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, The Natural History Museum [London] (NHM), The University of Tennessee [Knoxville], Berkeley Geochronology Center (BGC), NASA Johnson Space Center (JSC), NASA, Planetary Geosciences Institute [Knoxville], Department of Earth and Planetary Sciences [Knoxville], The University of Tennessee [Knoxville]-The University of Tennessee [Knoxville], Rice University [Houston], and American Geophysical Union
Subjects: gibert-delta, Jezero crater, delta, [SDU.STU.PL]Sciences of the Universe [physics]/Earth Sciences/Planetology, [SDU]Sciences of the Universe [physics], [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, Mars 2020, sedimentology, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, sedimentary architecture
Abstract: International audience; A key exploration target for the Perseverance rover mission is a sedimentary fan deposit at the western margin of Jezero crater, which has been interpretated to be a river delta that built into a lake basin during the Late Noachian-Early Hesperian epochs on Mars (~3.6-3.8 Ga). Images from the Mastcam-Z and SuperCam Remote Micro-Imager instruments provide striking views of the stratigraphy exposed in the fan’s erosional front. Here, we report its stratigraphy and sedimentology, which place constraints on the nature of the fan deposits and their paleoenvironmental implications.Multiple Mastcam-Z mosaics show spectacular views of the stratigraphy of a prominent embayment in the delta scarp that has been informally named Hawksbill Gap, the lower section of which the rover is investigating and sampling. The prominent cliffs of the eastern and western margin of Hawksbill Gap show distinctive stratal geometries with complex stratigraphic relations. The basal succession comprises poorly exposed thinly bedded, planar laminated sandstones that are interpreted as the deposits of low-density turbidity currents. A locally prominent, resistant unit named Rocky Top comprises planar stratified pebbly sandstones also likely to be high-density turbidite deposits. The stratigraphic mid-sections of the scarps are characterized by packages of decameter-scale inclined tabular strata. These tabular beds are locally conglomeratic but predominantly comprise finer-than-conglomerate lithologies, likely pebbly sandstones. Interstratified within these are poorly sorted matrix-supported conglomerates interpreted to be debris flow deposits. The inclined strata are overlain across a sharp truncation surface by generally planar parallel thin-bedded horizontal strata that we interpret as topset beds. Conglomerate beds containing bouldersare located within the overlying topset strata. The stratal patterns are broadly consistent with deposition in a Gilbert-type delta setting with basal strata representing deposition from sediment gravity flows, inclined strata representing foreset beds, and overlying topset beds deposition from fluvial processes in a delta top environment. The boulder conglomerates indicate sediment-transport on the delta top by episodic high-discharge floods.
Published: 2022

20. Pressure-Induced Stabilization and Insulator-Superconductor Transition of BH

Author: Guang-Rui Qian, Gilles Frapper, Andriy O. Lyakhov, Chao-Hao Hu, Artem R. Oganov, Huai-Ying Zhou, Qiang Zhu, Stony Brook University [SUNY] (SBU), State University of New York (SUNY), Guilin University of Electronic Technology, Geology Department, Geology Department, Moscow State University, Moscow 119992, Institut de Chimie des Milieux et Matériaux de Poitiers (IC2MP), and Université de Poitiers-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Ab initio, General Physics and Astronomy, chemistry.chemical_element, Insulator (electricity), 02 engineering and technology, 01 natural sciences, 7. Clean energy, Metal, chemistry.chemical_compound, Metastability, 0103 physical sciences, 010306 general physics, Boron, Superconductivity, [CHIM.ORGA]Chemical Sciences/Organic chemistry, [CHIM.CATA]Chemical Sciences/Catalysis, 021001 nanoscience & nanotechnology, Crystallography, chemistry, Covalent bond, visual_art, visual_art.visual_art_medium, 0210 nano-technology, [CHIM.OTHE]Chemical Sciences/Other, Diborane
Abstract: International audience; Diborane (B2H6), a high energy density material, was believed to be stable in a wide P, T interval. A systematic investigation of the B-H system using the ab initio variable-composition evolutionary simulations shows that boron monohydride (BH) is thermodynamically stable and can coexist with solid B, H2, and B2H6 in a wide pressure range above 50 GPa. B2H6 becomes unstable and decomposes into the Ibam phase of BH and H2 (C2/c) at 153 GPa. The semiconducting layered Ibam structure of BH at 168 GPa transforms into a metallic phase with space group P6/mmm and a 3D topology with strong B-B and B-H covalent bonds. The Ibam-P6/mmm transformation pathway suggests the possibility of obtaining the metastable Pbcm phase on cold decompression of the P6/mmm phase. The electron-phonon coupling calculations indicate that P6/mmm-BH is a phonon-mediated superconductor with a critical temperature of superconductivity (Tc) of 14.1-21.4 K at 175 GPa.
Published: 2013
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21. Chlorophyll and turbidity concentrations deduced from MODIS as an index of water quality of the Gulf of Gabes in 2009

Author: Rim Katlane, Cecile DUPOUY, Fouad Zargouni, 1 University of Sciences, Geology Department, Geomatic and Structural, Université de Tunis, CE, Institut méditerranéen d'océanologie (MIO), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Toulon (UTLN)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Toulon (UTLN), University of Sciences, Geology Department, Geomatic and Structural Ge, AUF, Collaboration publication avec Rim Katlane, Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), and Pin, Thierry
Subjects: [SDE.MCG] Environmental Sciences/Global Changes, MODIS, [SDE.MCG]Environmental Sciences/Global Changes, chlorophyll, Gulf of Gabes, turbidity
Abstract: Optical remote sensing was used to provide scientific information to support environmental management in the Gulf of Gabes located on the southeastern coast of Tunisia. This region is characterized by a shallow continental shelf with semi-diurnal tides. Since the early 1970s, industrial activity in this area may have contributed to the degradation of ecosystem biodiversity due to problems of eutrophication and the disappearance of benthic and planktonic species. Previous studies assessing the long term effects of anthropogenic and natural discharges on the Gulf of Gabes were based on regular seaborne measurements of total suspended matter, Secchi depth, turbidity, chlorophyll and temperature. However, these are often costly and difficult to obtain. The objective of this study is to carry out an optical remote sensing analysis with supporting in situ measurements of chlorophyll to monitor water quality and the impact of industrial discharges in the Gulf of Gabes. To start with, data provided both by the optical sensor and by our in situ sampling methods is described. Then, semi-empirical algorithms (OC3, OC5) are presented which are used to process Moderate Resolution Imaging Spectrometer MODIS data for retrieval of chlorophyll (CHL) and a validated algorithm for TU. A comparison was made between the derived estimates CHL and TU and the concurrent bio-optical in situ measurements at stations representing the coast and open ocean and produced significant correlations. The results obtained therefore confirm the high sensitivity and useful spatial coverage of MODIS data to provide a significant tool to accurately assess water quality parameters.
Published: 2012

22. Active surface faulting or landsliding in the Lower Tagus Valley (Portugal)? A solved controversy concerning the Vila Chã de Ourique site

Author: Fernando Marques, Paula M. Figueiredo, Luis Matias, João Cabral, Geology Department, Faculty of Sciences, and LATTEX/Instituto Dom Luiz, Universidade de Lisboa (ULISBOA), Geology Department, Faculty of Sciences, and CGUL, and Department of Geographic Engineering, Geophysics and Energy, Faculty of Sciences, and CeGUL/Instituto Dom Luiz
Subjects: Landsliding, 010504 meteorology & atmospheric sciences, Outcrop, Borehole, Induced seismicity, 010502 geochemistry & geophysics, 01 natural sciences, Alluvial plain, Surface faulting, Tectonics, Geophysics, Paleoseismicity, Geochemistry and Petrology, Mainland Portugal, Thrust fault, Alluvium, Structural geology, Lower Tagus Valley, Seismology, Geology, 0105 earth and related environmental sciences
Abstract: International audience; The Lower Tagus Valley has experienced significant (M 6-7) historical seismicity, evidencing the presence of seismogenic faults. These are still deficiently known due to the low strain rates and the recent alluvial sedimentation of the Tagus River that buries most of the structures, though Paleoseismic evidence was allegedly found by a research team in the Tagus valley, at a site 60 km N of Lisbon, near Vila Chã de Ourique (VCO). According to this team, trenching at the VCO site exposed an active thrust fault, evidencing the surface rupture of a large earthquake that occurred in 1531. Our studies performed at this site, comprising field observations with a reappraisal of the trench outcrops previously excavated, borehole drilling, soil mechanics laboratory testing, and seismic reflection acquisition, pointed to the alternative interpretation that the outcropping structures are gravitational and not of tectonic origin. The interpretation of new outcrops crosscutting the structures exposed at the trenches, as well as newly acquired high-resolution seismic reflection data, definitely exclude the active thrust fault explanation and support a gravitational slip model for all the observed structures. Gravitational slip in the river bank slope was promoted by low shear strength clays and high pore water pressure coupled with slope toe river erosion. Gravitational slides must have occurred prior to development of the present sedimentation level of the Tagus alluvial plain, which was attained in the last few thousand years as indicated by borehole data and estimations of sedimentation rates.
Published: 2010
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23. The Mastcam-Z Radiometric Calibration Targets on NASA's Perseverance Rover: Derived Irradiance Time-Series, Dust Deposition, and Performance over the First 350 Sols on Mars

Author: M. Merusi, K. B. Kinch, M. B. Madsen, J. F. Bell, J. N. Maki, A. G. Hayes, J. Joseph, J. R. Johnson, M. Rice, E. A. Cloutis, D. Applin, M. T. Lemmon, A. F. Vaughan, J. I. Núñez, E. Jensen, J. Z. Kristensen, K. Paris, E. Cisneros, M. R. Kennedy, O. Gasnault, Niels Bohr Institute [Copenhagen] (NBI), Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH), ASU School of Earth and Space Exploration (SESE), Arizona State University [Tempe] (ASU), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Department of Astronomy, Cornell University, Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Geology Department, Western Washington University, Western Washington University (WWU), Department of Geography [Winnipeg], University of Winnipeg, Space Science Institute [Boulder] (SSI), United States Geological Survey (USGS), School of Earth and Space Exploration [Tempe] (SESE), Institut de recherche en astrophysique et planétologie (IRAP), 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), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and 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)
Subjects: [SDU.STU.PL]Sciences of the Universe [physics]/Earth Sciences/Planetology, General Earth and Planetary Sciences, Environmental Science (miscellaneous)
Abstract: The Mastcam-Z radiometric calibration targets mounted on the NASA's Perseverance rover proved to be effective in the calibration of Mastcam-Z images to reflectance (I/F) over the first 350 sols on Mars. Mastcam-Z imaged the calibration targets regularly to perform reflectance calibration on multispectral image sets of targets on the Martian surface. For each calibration target image, mean radiance values were extracted for 41 distinct regions of the targets, including patches of color and grayscale materials. Eight strong permanent magnets, placed under the primary target, attracted magnetic dust and repelled it from central surfaces, allowing the extraction of radiance values from eight regions relatively clean from dust. These radiances were combined with reflectances obtained from laboratory measurements, a one-term linear fit model was applied, and the slopes of the fits were retrieved as estimates of the solar irradiance and used to convert Mastcam-Z images from radiance to reflectance. Derived irradiance time series are smoothly varying in line with expectations based on the changing Mars-Sun distance, being only perturbed by a few significant dust events. The deposition of dust on the calibration targets was largely concentrated on the magnets, ensuring a minimal influence of dust on the calibration process. The fraction of sunlight directly hitting the calibration targets was negatively correlated with the atmospheric optical depth, as expected. Further investigation will aim at explaining the origin of a small offset observed in the fit model employed for calibration, and the causes of a yellowing effect affecting one of the calibration targets materials.
Published: 2022
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24. Soil macroinvertebrate communities: A world‐wide assessment

Author: Patrick Lavelle, Jérôme Mathieu, Alister Spain, George Brown, Carlos Fragoso, Emmanuel Lapied, Adriana De Aquino, Isabelle Barois, Edmundo Barrios, Maria Eleusa Barros, Jose Camilo Bedano, Eric Blanchart, Mark Caulfield, Yamileth Chagueza, Jun Dai, Thibaud Decaëns, Anahi Dominguez, Yamileth Dominguez, Alexander Feijoo, Patricia Folgarait, Steven J. Fonte, Norma Gorosito, Esperanza Huerta, Juan Jose Jimenez, Courtland Kelly, Gladys Loranger, Robelio Marchão, Raphael Marichal, Catarina Praxedes, Leonardo Rodriguez, Guillaume Rousseau, Laurent Rousseau, Nuria Ruiz, Catalina Sanabria, Juan Carlos Suarez, Jerôme Ebagnerin Tondoh, Anne De Valença, Steven J. Vanek, Joel Vasquez, Elena Velasquez, Emily Webster, Chi Zhang, Institut d'écologie et des sciences de l'environnement de Paris (iEES Paris ), Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), perso, Adresse personnelle, Brazilian Agricultural Research Corporation (Embrapa), Instituto de Ecologia (INECOL), Taxonomia International Foundation, FAO Plant Production and Protection Division (FAO), Food and Agriculture Organization of the United Nations [Rome, Italie] (FAO), National University of Río Cuarto = Universidad Nacional de Río Cuarto (UNRC), Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Montpellier, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Colorado State University [Fort Collins] (CSU), Wageningen University and Research [Wageningen] (WUR), Universidad Nacional de Colombia [Bogotà] (UNAL), South China Agricultural University (SCAU), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Montpellier, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de Montpellier (UM), Universidad del Atlántico (UA), Universidad Tecnológica de Pereira [Colombie] (UTP), Universidad Nacional de Quilmes (UNQ), EI Colegio de la Frontera Sur (ECOSUR), Consejo Nacional de Ciencia y Tecnología [Mexico] (CONACYT), Instituto Pirenaico de Ecologia = Pyrenean Institute of Ecology (IPE), Université des Antilles (Pôle Guadeloupe), Université des Antilles (UA), Agrosystèmes Biodiversifiés (UMR ABSys), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre International de Hautes Etudes Agronomiques Méditerranéennes - Institut Agronomique Méditerranéen de Montpellier (CIHEAM-IAMM), Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Montpellier, Département Performances des systèmes de production et de transformation tropicaux (Cirad-PERSYST), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Museu Paraense Emílio Goeldi [Belém, Brésil] (MPEG), Universidad de la Amazonia [Caquetá], Universidade Estadual do Maranhão = State University of Maranhão (UEMA), Agence Nationale de la Recherche (ANR), Universidad del Valle [Cali] (Univalle), Université Nangui Abrogoua (UNA), Instituto de Investigaciones de la Amazonía Peruana (IIAP), Universidad Nacional de la Amazonía Peruana [Loreto, Perou] (UNAP), University of California [Davis] (UC Davis), University of California (UC), Empresa Brasileira de Pesquisa Agropecuária (Embrapa), Ministério da Agricultura, Pecuária e Abastecimento [Brasil] (MAPA), Governo do Brasil-Governo do Brasil, Geology Department, FCEFQyN, ICBIA-CONICET (National Scientific and Technical Research Council), National University of Río Cuarto, Farming Systems Ecology, College of Natural Resources and Environment, Université Paul-Valéry - Montpellier 3 (UPVM)-École Pratique des Hautes Études (EPHE), Soil Physics and Land Management Group, Instituto Pirenaico de Ecologìa = Pyrenean Institute of Ecology [Zaragoza] (IPE - CSIC), Department of biodiversity conservation and ecosystem restoration, Faculté des sciences exactes et naturelles (UFR SEN), Université des Antilles (UA)-Université des Antilles (UA), Centro de Pesquisa Agropecuária dos Cerrados, Embrapa Cerrados Planaltina, Coordenação de Zoologia, and We are grateful to Drs John Donaldson and Stella Zerbino for providing data from Australia and Uruguay, respectively, for the Macrofauna database.
Subjects: Global and Planetary Change, Ecology, Macrofauna database, P34 - Biologie du sol, Farm Systems Ecology Group, Bodemfysica en Landbeheer, soil ecology, Soil Physics and Land Management, communities, land cover, soil macroinvertebrates, L20 - Écologie animale, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, network analysis, Ecology, Evolution, Behavior and Systematics
Abstract: International audience; Aim: Macroinvertebrates comprise a highly diverse set of taxa with great potential as indicators of soil quality. Communities were sampled at 3,694 sites distributed world-wide. We aimed to analyse the patterns of abundance, composition and network characteristics and their relationships to latitude, mean annual temperature and rainfall, land cover, soil texture and agricultural practices. Location: Sites are distributed in 41 countries, ranging from 55 degrees S to 57 degrees N latitude, from 0 to 4,000 m in elevation, with annual rainfall ranging from 500 to >3,000 mm and mean temperatures of 5-32 degrees C. Time period: 1980-2018. Major taxa studied: All soil macroinvertebrates: Haplotaxida; Coleoptera; Formicidae; Arachnida; Chilopoda; Diplopoda; Diptera; Isoptera; Isopoda; Homoptera; Hemiptera; Gastropoda; Blattaria; Orthoptera; Lepidoptera; Dermaptera; and "others". Methods: Standard ISO 23611-5 sampling protocol was applied at all sites. Data treatment used a set of multivariate analyses, principal components analysis (PCA) on macrofauna data transformed by Hellinger's method, multiple correspondence analysis for environmental data (latitude, elevation, temperature and average annual rainfall, type of vegetation cover) transformed into discrete classes, coinertia analysis to compare these two data sets, and bias-corrected and accelerated bootstrap tests to evaluate the part of the variance of the macrofauna data attributable to each of the environmental factors. Network analysis was performed. Each pairwise association of taxonomic units was tested against a null model considering local and regional scales, in order to avoid spurious correlations. Results: Communities were separated into five clusters reflecting their densities and taxonomic richness. They were significantly influenced by climatic conditions, soil texture and vegetation cover. Abundance and diversity, highest in tropical forests (1,895 +/- 234 individuals/m(2)) and savannahs (1,796 +/- 72 individuals/m(2)), progressively decreased in tropical cropping systems (tree-associated crops, 1,358 +/- 120 individuals/m(2); pastures, 1,178 +/- 154 individuals/m(2); and annual crops, 867 +/- 62 individuals/m(2)), temperate grasslands (529 +/- 60 individuals/m(2)), forests (232 +/- 20 individuals/m(2)) and annual crops (231 +/- 24 individuals/m(2)) and temperate dry forests and shrubs (195 +/- 11 individuals/m(2)). Agricultural management decreased overall abundance by
Published: 2022
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25. Invasion of a Widespread, Non‐Native Grass Causes Downstream Reductions in Bioavailable Silica

Author: Laura D. Triplett, Zachary Wagner, Michal Tal, Karin M. Kettenring, Geology Department, Gustavus Adolphus College, 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), and Utah State University (USU)
Subjects: 0106 biological sciences, 010504 meteorology & atmospheric sciences, Ecology, 010604 marine biology & hydrobiology, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Biogeochemistry, Sediment, 15. Life on land, Riparian ecology, 01 natural sciences, Nutrient, Downstream (manufacturing), Environmental science, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Earth-Surface Processes, Water Science and Technology
Abstract: International audience
Published: 2020
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26. A preliminary study of paleotsunami deposit along the south coast of East Java: Pacitan-Banyuwangi

Author: Aswan, null [Geology Department, Faculty of Earth Sciences and Technology - Bandung Institute of Technolog, Bandung (Indonesia)]
Published: 2015
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27. Hadean zircon formed due to hydrated ultramafic protocrust melting

Author: Oleg Melnik, Anastassia Y. Borisova, Brigitte Stoll, Ilya N. Bindeman, Georges Ceuleneer, Anne Nédélec, Gleb S. Pokrovski, Oleg G. Safonov, Michael J. Toplis, Andrew Y. Bychkov, Klaus Peter Jochum, Andrey A. Gurenko, W. A. Bohrson, Nail R. Zagrtdenov, Ulrike Weis, Geology Department, Moscow State University, Moscow 119992, 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), 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), 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), and 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)
Subjects: 010504 meteorology & atmospheric sciences, Ultramafic rock, [SDU]Sciences of the Universe [physics], Hadean, Geochemistry, Geology, 010502 geochemistry & geophysics, 01 natural sciences, 0105 earth and related environmental sciences, Zircon
Abstract: Hadean zircons, from the Jack Hills (Western Australia) and other localities, are currently the only window into the earliest terrestrial felsic crust, the formation of which remains enigmatic. Based upon new experimental results, generation of such early crust has been hypothesized to involve the partial melting of hydrated peridotite interacting with basaltic melt at low pressure (
Published: 2021
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28. Derivation of Hawaiian rejuvenated magmas from deep carbonated mantle sources: A review of experimental and natural constraints

Author: Anastassia Y. Borisova, Romain Tilhac, Geology Department, Moscow State University, Moscow 119992, 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), 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), Ministerio de Ciencia e Innovación (España), European Commission, 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), and 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)
Subjects: Pyroxenit, 010504 meteorology & atmospheric sciences, Geochemistry, Review, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Mantle sources of carbonatite melts, Mantle (geology), Rejuvenated stage, Xenolith, Metasomatism, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Melt inclusions, Basalt, Nephelinite, Hawaiian magmatism, Carbonatite metasomatism, Melilite, 13. Climate action, [SDU]Sciences of the Universe [physics], Carbonatite, engineering, General Earth and Planetary Sciences, Open-system melting, Geology
Abstract: The role of carbon-rich or carbonatitic melts as an important metasomatizing agent in the Earth's mantle is supported by direct and indirect evidence of their involvement, ranging from the presence of erupted carbonatitic lavas to metasomatic reactions documented in minerals and melt inclusions from mantle xenoliths. Carbonatite metasomatism in hot-spot settings, and more particularly in the mantle sources of rejuvenated Hawaiian lavas, has long been suspected. However, an unequivocal geochemical tracer of carbonated mantle sources in alkaline volcanic suites is still missing. We here examine high-quality major- and trace-element compositions of ~400 primitive Hawaiian lavas (MgO = 8.5–21 wt%, SiO = 37–50 wt%) and associated xenoliths, focusing on those erupted during rejuvenated stages of activity of the Hawaiian hot spot, Pacific Ocean. The rejuvenated-stage alkaline lavas are the most enriched in volatile elements among the four-stage Hawaiian lavas. Our compilation shows that these rejuvenated-stage lavas range from melilite/nephelinite to transitional basalts and are characterized by low-Si and high-Na, -K and -Ca contents, along with the enrichment of REE, Th and Ba relative to K, Hf, Zr, Ti and Nb. Their trace-element systematics argues against derivation from a homogeneous lherzolitic or pyroxenitic source, regardless of the involvement of residual garnet or hydrous phases. Based on a comprehensive review of natural and experimental constraints on partitioning between carbonatites and mantle minerals and numerical simulations of open-system melting, we show that it is rather consistent with carbonatite metasomatism in their source. Variations in SiO, CaO, alkali contents and trace-element proxies such as Hf/Sm also specify temporal variations in the depth of melting and/or the respective contribution of lherzolites and pyroxenites in a hybrid (probably asthenospheric) source fluxed by carbonatitic melts. We suggest that this episode took place ≤4.2 Ma at temperatures and pressures in excess of 1100 °C and 2 GPa. The low-solidus carbonatite melts were likely generated following a time lag which allowed for cooling of the plume and likely derived from an ancient (>1Ga), recycled mantle, or lower mantle, source in the Hawaiian plume, in good agreement with Sr-Nd-Hf-Os isotope systematics and other chemical and mineralogical features of Hawaiian rejuvenated lavas and xenoliths. The identification of a deep carbonated mantle source for Hawaiian rejuvenated volcanic series is also in line with noble gas and light stable isotope systematics and suggests that the interaction between carbonatite melts and peridotites/pyroxenites may be a critical process explaining the compositional variability of many oceanic island magmas., We are grateful to L.V. Dmitriev, F.A. Frey, N. Mattielli, D. Weis, J. Scoates, V. Kamenetsky, M. Grégoire, M. Rabinowicz for their very helpful comments and suggestions, and to M.S.N. Carpenter for the English proofreading. Editor Arturo Gomez-Tuena, M. Bizimis and an anonymous reviewer are also thanked for their constructive criticism which significantly improved this paper. Romain Tilhac acknowledges a “ Juan de la Cierva-formación ” Fellowship ( FJC2018-036729 ) granted by the Spanish Ministry of Science and Innovation and co-funded by the European Development Fund and the European Social Fund.
Published: 2021
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29. The trisulfur radical ion S 3 •− controls platinum transport by hydrothermal fluids

Author: Elsa Desmaele, Maria A. Kokh, Denis Testemale, Jean-Louis Hazemann, Elena F. Bazarkina, Antonino Marco Saitta, Anastassia Y. Borisova, Clément Laskar, Gleb S. Pokrovski, G. Ferlat, Rodolphe Vuilleumier, 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), 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), Institut für Geowissenschaften [Potsdam], Universität Potsdam, Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Matériaux, Rayonnements, Structure (MRS), Institut Néel (NEEL), 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)-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), Geological Department, Moscow State University, Lomonosov Moscow State University (MSU), 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), Geology Department, Moscow State University, Moscow 119992, 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), University of Potsdam = Universität Potsdam, École normale supérieure - Paris (ENS-PSL), Matériaux, Rayonnements, Structure (NEEL - MRS), Processus d'Activation Sélective par Transfert d'Energie Uni-électronique ou Radiatif (UMR 8640) (PASTEUR), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and ANR-16-CE31-0017,RADICALS,Les radicaux de soufre et leurs applications pour les ressources minérales, l'évolution des magmas et la géochimie isotopique(2016)
Subjects: 010504 meteorology & atmospheric sciences, Sulfide, Inorganic chemistry, hydrothermal fluid, chemistry.chemical_element, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Hydrothermal circulation, chemistry.chemical_compound, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Trisulfur, platinum group elements, Hydrothermal synthesis, [CHIM.COOR]Chemical Sciences/Coordination chemistry, platinum, 0105 earth and related environmental sciences, trisulfur ion, chemistry.chemical_classification, Multidisciplinary, Aqueous solution, chemistry, [SDU]Sciences of the Universe [physics], 13. Climate action, sulfur, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], engineering, Hydroxide, Noble metal, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Platinum, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
Abstract: International audience; Platinum group elements (PGE) are considered to be very poorly soluble in aqueous fluids in most natural hydrothermal–magmatic contexts and industrial processes. Here, we combined in situ X-ray absorption spectroscopy and solubility experiments with atomistic and thermodynamic simulations to demonstrate that the trisulfur radical ion S 3 •− forms very stable and soluble complexes with both Pt II and Pt IV in sulfur-bearing aqueous solution at elevated temperatures (∼300 °C). These Pt-bearing species enable (re)mobilization, transfer, and focused precipitation of platinum up to 10,000 times more efficiently than any other common inorganic ligand, such as hydroxide, chloride, sulfate, or sulfide. Our results imply a far more important contribution of sulfur-bearing hydrothermal fluids to PGE transfer and accumulation in the Earth’s crust than believed previously. This discovery challenges traditional models of PGE economic concentration from silicate and sulfide melts and provides new possibilities for resource prospecting in hydrothermal shallow crust settings. The exceptionally high capacity of the S 3 •− ion to bind platinum may also offer new routes for PGE selective extraction from ore and hydrothermal synthesis of noble metal nanomaterials.
Published: 2021
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30. Experimental diopsidite: Implications for natural diopsidite genesis through fluid-melt-mantle peridotite reaction

Author: Michael J. Toplis, Anastassia Y. Borisova, Oleg G. Safonov, Georges Ceuleneer, Nail R. Zagrtdenov, Geology Department, Moscow State University, Moscow 119992, Géosciences Environnement Toulouse (GET), 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), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), 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), 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), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), 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)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, 010504 meteorology & atmospheric sciences, Diopsidite, Hydrated peridotite, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Mantle (geology), Oceanic lithosphere, Geochemistry and Petrology, Lithosphere, Transition zone, Petrology, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Peridotite, Diopside, Partial melting, Forsterite, Mantle-crust transition zone, Igneous rock, Geophysics, 13. Climate action, [SDU]Sciences of the Universe [physics], visual_art, engineering, visual_art.visual_art_medium, Melt-rock reaction experiment Editorial handling: A. R. Chakhmouradian
Abstract: International audience; Occurrences of diopsidites, rocks made predominantly of gem-like diopside whose composition precludes a purely igneous origin, allow tracking the pathway of high-temperature fluids and fluid-saturated melts in the oceanic lithosphere in vicinity of the mantle-crust transition zone (the Moho) and the adjacent mantle in an oceanic setting. We have experimentally explored the origin of the mantle diopsidites by reacting serpentinite with synthetic haplobasaltic glass (corresponding to anorthite-diopside eutectic at 0.1 MPa pressure) at 900 and 1250 °C, and 0.2 GPa pressure for 120 h. At 900 °C, no reaction is observed in the sample; in contrast, in the experimental runs heated to 1250 °C, we distinguish two mineral associations (1) early Al-poor diopside [Mg# = Mg/(Mg + Fe) = 99 ± 1; Al2O3 = 1.9 ± 1.6 wt%] with the diopside-hosted forsterite (Fo 99.2 ± 0.1) inclusions and (2) late Al-enriched diopside (Mg# = 98 ± 1; Al2O3 = 3.7 ± 2.8 wt%). Our experiments confirm that mantle diopsidites can be produced at ≥ 1100 °C in response to partial melting of hydrated peridotite (serpentinite) in the presence of haplobasaltic melt and aqueous fluid at the conditions typical of the mantle-crust transition zone and the shallow mantle beneath oceanic spreading ridges.
Published: 2021
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31. Early Sasanian landscape modification: New geoarchaeological evidence from the Ardashir Pond in southwest Iran (Palace of Ardashir, third century CE)

Author: Andrew C. Parnell, Cyril Aubert, Alireza Askari-Chaverdi, François Demory, Abdolmajid Naderi-Beni, Nicolas Faucherre, Elodie Brisset, Elnaz Rashidian, Nick Marriner, Hamid Lahijani, Morteza Djamali, Emmanuel Gandouin, 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), Institute of Archaeology, Department of the Archaeology of the Ancient Near East, Goethe University Frankfurt, History Department, Shiraz University, Shiraz, Iran, 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), Laboratoire d'Archéologie Médiévale et Moderne en Méditerranée (LA3M), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Iranian National Institute for Oceanography and Atmospheric Sciences (INIOAS), Théoriser et modéliser pour aménager (UMR 6049) (ThéMA), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Marine Geology Department, Iranian National Institute for Oceanography and Atmospheric Science (INIOAS), Insight Centre for Data Analytics, Hamilton Institute, Maynooth University, Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Centre National de la Recherche Scientifique (CNRS)-Université de Bourgogne (UB)-Université de Franche-Comté (UFC), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Université de Franche-Comté (UFC), and Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Université de Bourgogne (UB)
Subjects: 010506 paleontology, Archeology, geography.geographical_feature_category, Sediment, Sasanian architecture, Wetland, human intervention, waterresource, Structural basin, landscape, 010502 geochemistry & geophysics, 01 natural sciences, Archaeology, Sedimentary depositional environment, Late Antiquity, Geography, World heritage, [SDE]Environmental Sciences, Earth and Planetary Sciences (miscellaneous), Period (geology), 0105 earth and related environmental sciences
Abstract: International audience; The Sasanian period (224–651 CE) marked an era of large-scale urban projects in southwest Asia, including Iran's semi-arid highlands, with particular efforts to manipulate water bodies. This study presents a recent interdisciplinary investigation of a spring-fed pond at the entrance of the Palace of Ardashir (Firuzabad plain, southwest Iran), part of a recently registered World Heritage site. Historical accounts suggest that the entire water system of the plain, including the pond, underwent a hydraulic re-organization at the beginning of the Sasanian period, a fact that has never been investigated geoarchaeologically. A series of sediment cores were retrieved from the pond to probe its evolution and examine the extent of its landscape modification. The cores were sedimentologically described and radiocarbon-dated with age–depth models established based on 57 AMS (accelerator mass spectrometry) 14C dates to understand the basin's depositional history. The results indicate that (i) Ardashir Pond has existed as part of a larger wetland complex since at least 4500 years ago, (ii) it was substantially enlarged at the beginning of the Sasanian era, and (iii) it was abandoned at the end of the Sasanian period. The Ardashir Pond is one of the first geoarchaeologically investigated case studies to demonstrate the Sasanian landscape in the framework of the “Iranshahr” sociopolitical concept.
Published: 2021
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32. On the cratonization of the Arabian-Nubian Shield: Constraints from gneissic granitoids in south Eastern Desert, Egypt

Author: Ali A. Khudeir, Loretta Corcoran, Åke Johansson, Jean-Louis Paquette, Kirsten N. Nicholson, Tyrone O. Rooney, Mohamed A. El-Fadly, Mohamed A. Abu El-Rus, Shawn J. Malone, Sadiq Hamid, Geology Department, Faculty of Science, Assiut University, Asyut, 71516, Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement et la société-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Ball State University, Department of Geological Sciences, 117 Fine Art Building, Muncie, IN 47306, Department of Geosciences, Swedish Museum of Natural History, Stockholm SE-104 05, Sweden, Department of Geological Sciences, Michigan State University, East Lansing, MI 48824, and Notre Dame University, Department of Civil & Environmental Engineering & Earth Sciences, 156 Fitzpatrick Hall, Notre Dame, IN 46556
Subjects: 010504 meteorology & atmospheric sciences, Mantle wedge, MESH: Partial melting, MESH: Subduction zones, Geochemistry, Partial melting, 010502 geochemistry & geophysics, 01 natural sciences, MESH: Arabian-Nubian Shield (ANS), [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Fractional crystallization, Cratonization, Arabian-Nubian Shield (ANS), MESH: Tonalite-Trondhjemite-granodiorite (TTG), Subduction zones, Tonalite-Trondhjemite-granodiorite (TTG), 0105 earth and related environmental sciences, QE1-996.5, Underplating, Fractional crystallization (geology), Geology, MESH: Cratonization, Fractional crystallization, Magma, General Earth and Planetary Sciences, Island arc, Protolith, Zircon
Abstract: International audience; The Shaitian granite complex (SGC) spans more than 80 Ma of crustal growth in the Arabian–Nubian Shield in southeast Egypt. It is a voluminous composite intrusion (60 km2) comprising a host tonalite massif intruded by subordinate dyke-like masses of trondhjemite, granodiorite and monzogranite. The host tonalite, in turn, encloses several, fine-grained amphibolite enclaves. U-Pb zircon dating indicates a wide range of crystallization ages within the SGC (800 ± 18 Ma for tonalites; 754 ± 3.9 Ma for trondhjemite; 738 ± 3.8 Ma for granodirite; and 717±3.2 Ma for monzogranite), suggesting crystallization of independent magma pulses. The high positive εNdi (+6–+8) indicate that the melting sources were dominated by juvenile material without any significant input from older crust. Application of zircon saturation geothermometry indicates increasing temperatures during the generation of melts from 745±31 °C for tonalite to 810±25 °C for trondhjemite; 840±10 °C for granodiorite; and 868±10 °C for monzogranite. The pressure of partial melting is loosely constrained to be below the stability of residual garnet (3 kbar for the stability of residual amphibole as inferred from the significantly lower NbN and TaN compared with LREEN and the sub-chondrite Nb/Ta ratios exhibited by the granitic phases. The inverse relation between the generation temperatures and the ages estimates of the granitoid lithologies argue against a significant role of fractional crystallization. The major and trace element contents indicate the emplacement of SGC within a subduction zone setting. It lacks distinctive features for melt derived from a subducted slab (e.g. high Sr/Y and high (La/Yb)N ratios), and the relatively low MgO and Ni contents in all granite phases within the SGC suggest melting within the lower crust of an island arc overlying a mantlewedge. Comparisonwith melts produced during melting experiments indicates an amphibolite of basaltic composition is the best candidate as source for the tonalite, trondhjemite and granodiorite magmas whereas the monzogranite magma is most consistent with fusion of a tonalite protolith. Given the overlapping Nd-Sr isotope ratios as well as several trace element ratios betweenmonzogranite and tonalite samples, it is reasonable to suggest that the renewed basaltic underplating may have caused partial melting of tonalite and the emplacement of monzogranite melt within the SGC. The emplacement of potassic granite (monzogranite) melts subsequent to the emplacement of Na-rich granites (tonalite-trondhjemite-granodiorite) most likely suggests major crustal thickening following arc collision andamalgamation into the over thickened proto-crust of the Arabian-Nubian microcontinent. Eventually, after complete consolidation, the whole SGC was subjected to regional deformation, most probably during accretion to the Saharan Metacraton (arc–continent collisions) in the late Cryogenian -Ediacaran times (650–542 Ma).
Published: 2021
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33. Facing water shortages in ancient Iran: new evidence from sedimentary records of the Southern Zagros and historical insights

Author: Brisset, Elodie, Djamali, Morteza, Ricci, Andrea, Balatti, Silvia, Beni, Abdolmajid Naderi, Azadi, Ahmad, Firoozbakhsh, Pejman, 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), Institute for Prehistoric and Protohistoric Archaeology, Kiel University, Kiel, Germany, Institut für Klassische Altertumskunde, Abt. Alte Geschichte, Kiel University, Kiel, Germany, Marine Geology Department, Iranian National Institute for Oceanography and Atmospheric Science (INIOAS), Research Institute of Cultural Heritage and Tourism (RICHT), Iranian Center for Archaeological Research (ICAR), Tehran, Iran, and Brisset, Elodie
Subjects: [SDV.EE]Life Sciences [q-bio]/Ecology, environment, [SHS.ARCHEO] Humanities and Social Sciences/Archaeology and Prehistory, [SDU.STU.GM] Sciences of the Universe [physics]/Earth Sciences/Geomorphology, Drought, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, Achaemenid, Persepolis, Water, Iran, Lake, [SDV.EE] Life Sciences [q-bio]/Ecology, environment, Sassanid, Qanat, [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2021

34. Editorial: Magma-Rock and Magma-Mush Interactions as Fundamental Processes of Magmatic Differentiation

Author: Anastassia Y. Borisova, Wendy A. Bohrson, Frank J. Spera, Geology Department, Moscow State University, Moscow 119992, Géosciences Environnement Toulouse (GET), 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), 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), 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: magma-rock interaction, 010504 meteorology & atmospheric sciences, editorial, magma-mush system, 010502 geochemistry & geophysics, melt-rock interaction, 01 natural sciences, [SDU]Sciences of the Universe [physics], Magma, General Earth and Planetary Sciences, Igneous differentiation, lcsh:Q, 10. No inequality, Petrology, melt-mush reaction, lcsh:Science, Geology, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: International audience
Published: 2021
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35. Experimental Study of Pt Solubility in the CO-CO2 Fluid at Low fO2 and Subsolidus Conditions of the Ultramafic-Mafic Intrusions

Author: Olga Shaposhnikova, A. G. Simakin, Gleb S. Pokrovski, Oksana Tyutyunnik, T. P. Salova, Alexey N. Nekrasov, Sergey I. Isaenko, Galina Bondarenko, Anastassia Y. Borisova, Geology Department, Moscow State University, Moscow 119992, Géosciences Environnement Toulouse (GET), 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), ANR-16-CE31-0017,RADICALS,Les radicaux de soufre et leurs applications pour les ressources minérales, l'évolution des magmas et la géochimie isotopique(2016), 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), 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: platinum carbonyl, Materials science, lcsh:QE351-399.2, 010504 meteorology & atmospheric sciences, Whiskers, Analytical chemistry, isoferroplatinum, chemistry.chemical_element, carbonic fluid, 010502 geochemistry & geophysics, 01 natural sciences, mafic-ultramafic intrusion, chemistry.chemical_compound, Albite, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Acetone, platinum, Solubility, Porosity, Quartz, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Quenching, lcsh:Mineralogy, Geology, Geotechnical Engineering and Engineering Geology, chemistry, 13. Climate action, Platinum, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
Abstract: The solubility of Pt in CO-CO2 fluid was studied experimentally at P = 50–200 MPa and T = 950 °C. A mixture of MgC2O4 and MgCO3 was used as a source of the fluid. Upon the reaction of the Pt capsule walls and the fluid, a carbonyl of platinum is formed. The use of the high-temperature quartz ceramics as a fluid trap avoids the effect of mechanical contamination with Pt from the eroded capsule walls. The total content of platinum in the porous fluid traps was measured by the Electrothermal Atomic Absorption (ET-AAS) method. In some experiments, the local analysis of traps was carried out by the Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) method. The composition of fluid in bubbles captured in an albite glass trap was studied by micro-Raman spectroscopy. On the capsule walls and MgO, Pt “whiskers” of submicron diameter were observed, which were formed as a product of carbonyl decomposition during quenching. About 5–15% of carbonyl withstands quenching resulting in 1.5 to 2 ppm Pt soluble in acetone (runs at P = 200 MPa) in a quartz glass trap. The amount of Pt soluble in acetone from the capsule walls corresponds to a concentration of up to 8 ppm in the fluid. A high content of soluble Pt of 2000–3000 ppm was determined in a carbon coated MgO matrix. Our study demonstrated that the solubility of Pt in the CO-CO2 fluid is 15–150 ppm, presumably in the form of Pt3(CO)62− under conditions corresponding to the conditions of the subsolidus stage of layered ultramafic-mafic and ultramafic-alkaline intrusions formation. Our preliminary data showed that this solubility will increase with the addition of water at low fO2.
Published: 2021
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36. Petrochemical and Mineralogical Constraints on the Source and Processes of Uranium Mineralisation in the Granitoids of Zing-Monkin Area, Adamawa Massif, NE Nigeria

Author: Mamman, Y [Federal University of Technology, Geology Department (Nigeria)]
Published: 2011
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37. Zircon survival in shallow asthenosphere and deep lithosphere

Author: Nail R. Zagrtdenov, Anastassia Y. Borisova, Marion Marchelli, Andrew Y. Bychkov, Jérôme Fehrenbach, Oleg Melnik, Oleg G. Safonov, Svyatoslav Shcheka, Michael J. Toplis, Jérémy Guignard, Ilya N. Bindeman, Geology Department, Moscow State University, Moscow 119992, Géosciences Environnement Toulouse (GET), 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), 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), 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: Earth and Planetary Astrophysics (astro-ph.EP), Zircon, Condensed Matter - Materials Science, 010504 meteorology & atmospheric sciences, experiment, Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, basaltic melt, 010502 geochemistry & geophysics, 01 natural sciences, mineral dissolution, asthenosphere, Geophysics, 13. Climate action, Geochemistry and Petrology, Asthenosphere, Lithosphere, [SDU]Sciences of the Universe [physics], [SDE]Environmental Sciences, lithosphere, Petrology, Geology, 0105 earth and related environmental sciences, Astrophysics - Earth and Planetary Astrophysics
Abstract: Zircon is the most frequently used mineral for dating terrestrial and extraterrestrial rocks. However, the system of zircon in mafic/ultramafic melts has been rarely explored experimentally and most existing models based on the felsic, intermediate and/or synthetic systems are probably not applicable for prediction of zircon survival in terrestrial shallow asthenosphere. In order to determine the zircon stability in such natural systems, we have performed high-temperature experiments of zircon dissolution in natural mid-ocean ridge basaltic and synthetic haplobasaltic melts coupled with in situ electron probe microanalyses of the experimental products at high current. Taking into account the secondary fluorescence effect in zircon glass pairs during electron microprobe analysis, we have calculated zirconium diffusion coefficient necessary to predict zircon survival in asthenospheric melts of tholeiitic basalt composition. The data imply that typical 100 micron zircons dissolve rapidly (in 10 hours) and congruently upon the reaction with basaltic melt at mantle pressures. We observed incongruent (to crystal ZrO2 and SiO2 in melt) dissolution of zircon in natural mid-ocean ridge basaltic melt at low pressures and in haplobasaltic melt at elevated pressure. Our experimental data raise questions about the origin of zircons in mafic and ultramafic rocks, in particular, in shallow oceanic asthenosphere and deep lithosphere, as well as the meaning of the zircon-based ages estimated from the composition of these minerals. Large size zircon megacrysts in kimberlites, peridotites, alkali basalts and other magmas suggest the fast transport and short interaction between zircon and melt.The origin of zircon megacrysts is likely related to metasomatic addition of Zr into mantle as any mantle melting episode should obliterate them., This 30 pages manuscript submitted to American Mineralogist contains 5 figures and 1 table
Published: 2020
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38. High pressure and temperatures during the early stages of tungsten deposition at Panasqueira revealed by fluid inclusions in topaz

Author: Michel Cathelineau, Maxime Dour, Christian Marignac, Mélanie Dejean, Filipe Pinto, Marie-Christine Boiron, Laurent Truche, Eleonora Carocci, 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), Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Grenoble Alpes (UGA)-Université Gustave Eiffel-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Beralt Tin & Wolfram, Geology Department, Instituto de Ciências da Terra, Universidade do Porto, ANR-14-EMIN-0001,NewOreS,Development of New models for the genesis of Rare Metal (W, Nb, Ta, Li) Ore deposits from the European Variscan Belt and valorization of low grade and fine grained ore and mine tailings(2014), ANR-10-LABX-0021,RESSOURCES21,Strategic metal resources of the 21st century(2010), Institut national des sciences de l'Univers (INSU - CNRS)-Centre de recherches sur la géologie des matières premières minérales et énergétiques (CREGU)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), 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 Gustave Eiffel-Université Grenoble Alpes (UGA), and Universidade do Porto = University of Porto
Subjects: P-T path, 020209 energy, Geochemistry, Topaz, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, 02 engineering and technology, engineering.material, Deep crustal level, 010502 geochemistry & geophysics, 01 natural sciences, Tungsten, Ore genesis, Geochemistry and Petrology, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, 0202 electrical engineering, electronic engineering, information engineering, Fluid inclusions, Quartz, 0105 earth and related environmental sciences, Panasqueira, Geology, Metamorphic fluids, Magma, engineering, Economic Geology, Inclusion (mineral), Vein (geology)
Abstract: International audience; The Variscan vein-type Panasqueira W-Sn(Cu) deposit, one of the main tungsten deposits in Western Europe, has a long and complicated geological history. The first vein infillings, which consist of the quartz-wolframite association as well as the first generation of topaz, underwent significant deformation. As a consequence, most fluid inclusions of the earliest hydrothermal event are deformed and destroyed. Two preserved fluid inclusion assemblages are, however, found in the topaz overgrowth band and are dense aqueous-carbonic inclusions as well as dense CO2 dominated fluid inclusions. The P-T conditions of fluid trapping are constrained by using the intersection between isochores, as well as graphite-water equilibrium data and yield the following trapping conditions: 500 ± 20°C and 250 ± 20 MPa. These P-T conditions are incompatible with fluid unmixing. Fluid chemistry results from water-graphite equilibrium, probably in metapelites, at two distinct temperatures: around 450-500°C for the predominant aqueous-carbonic fluid, and higher temperatures of maximal 550°C for the CO2-rich fluid enriched in N2. These P-T estimates are consistent with deep crustal levels around 8-10 km depth and a high geothermal gradient around c. 60°C/km-1. The ascending non-magmatic fluids, enriched in volatiles, are essential in the ore genesis. The high thermal gradients may be related either to new magma pulse after the formation of the Panasqueira granite intrusion or to anomalous heat flux produced by the hot fluids ascending from migmatitic levels present at greater depth. This hypothesis necessitates to consider the role of a crustal weakness, which is attested both by the successive intrusions of several granitic magmas at the same place, and the presence of inherited quartz filled structures so-called Seixo-Bravo found only in the Panasqueira area.
Published: 2020
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39. Impact of dams and climate change on suspended sediment flux to the Mekong delta

Author: Gianbattista Bussi, Li Jin, Craig W. Hutton, Tristan Berchoux, Daniel R. Parsons, Christopher Hackney, Simon Dadson, Hal Voepel, Paul Whitehead, Grigorios Vasilopoulos, Stephen E. Darby, Andrew Nicholas, School of Geography and the Environment [Oxford] (SoGE), University of Oxford [Oxford], School of Geography and Environmental Sciences, University of Southampton, Geology Department, Suny Cortland, Partenaires INRAE-Partenaires INRAE, Energy and Environment Institute, University of Hull [United Kingdom], School of Geography, Politics and Sociology, Newcastle University, Newcastle upon Tyne, UK., Newcastle University [Newcastle], Centre International de Hautes Etudes Agronomiques Méditerranéennes - Institut Agronomique Méditerranéen de Montpellier (CIHEAM-IAMM), Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM), Territoires, Environnement, Télédétection et Information Spatiale (UMR TETIS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Exeter University - Department of geography, University of Exeter, and Biotechnology and Biological Sciences Research Council (BBSRC)NERC Natural Environment Research Council
Subjects: Delta, ASIE DU SUD EST, Environmental Engineering, 010504 meteorology & atmospheric sciences, CLIMATIC CHANGE, MODELS, Drainage basin, Fluvial, Climate change, 010501 environmental sciences, 01 natural sciences, [SHS]Humanities and Social Sciences, MODELE, DELTAS, BARRAGE, Environmental Chemistry, SOIL FERTILITY, 14. Life underwater, Waste Management and Disposal, SEDIMENTATION, DAMS, 0105 earth and related environmental sciences, Hydrology, geography, geography.geographical_feature_category, DELTA, FERTILITE DU SOL, Sediment, [SDV.SA.AEP]Life Sciences [q-bio]/Agricultural sciences/Agriculture, economy and politics, 15. Life on land, Pollution, 6. Clean water, Current (stream), BASSIN VERSANT, WATERSHEDS, 13. Climate action, CHANGEMENT CLIMATIQUE, Environmental science, Climate model, SOUTH EAST ASIA, Sediment transport
Abstract: International audience; The livelihoods of millions of people living in the world's deltas are deeply interconnected with the sediment dynamics of these deltas. In particular a sustainable supply of fluvial sediments from upstream is critical for ensuring the fertility of delta soils and for promoting sediment deposition that can offset rising sea levels. Yet, in many large river catchments this supply of sediment is being threatened by the planned construction of large dams. In this study, we apply the INCA hydrological and sediment model to the Mekong River catchment in South East Asia. The aim is to assess the impact of several large dams (both existing and planned) on the suspended sediment fluxes of the river. We force the INCA model with a climate model to assess the interplay of changing climate and sediment trapping caused by dam construction. The results show that historical sediment flux declines are mostly caused by dams built in PR China and that sediment trapping will increase in the future due to the construction of new dams in PDR Lao and Cambodia. If all dams that are currently planned for the next two decades are built, they will induce a decline of suspended sediment flux of 50% (47–53% 90% confidence interval (90%CI)) compared to current levels (99 Mt/year at the delta apex), with potentially damaging consequences for local livelihoods and ecosystems.
Published: 2020
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40. Recent geospatial dynamics of Terceira (Azores, Portugal) and the theoretical implications for the biogeography of active volcanic islands

Author: Paulo A. V. Borges, Arie C. Seijmonsbergen, W.M. de Boer, Sietze J. Norder, Kenneth F. Rijsdijk, Stacy Shinneman, S.M. Teixeira de Medeiros, S. Buijs, Rui B. Elias, Paolo Stocchi, Erik F. M. Koene, Carlos S. Melo, Rui Quartau, Robin Aguilée, J.C. Carreiro Nunes, Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Amsterdam, Deltares, Utrecht, The Netherlands, Instituto Hidrográfico, Lisboa, Instituto Dom Luiz, Lisboa, Evolution et Diversité Biologique (EDB), 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, CIBIO-Açores, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Pólo dos Açores, Azores, Geology Department, Faculty of Sciences, University of Lisbon, Centre for Ecology, Evolution and Environmental Changes (cE3c) /Azorean Biodiversity Group and Universidade dos Açores - Faculdade de Ciências Agrárias e do Ambiente, Angra do Heroísmo, Açores, Coast Systems Department, NIOZ sea level centre, Den Burg (Texel), Institut für Geophysik [Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Centre for Ecology, Evolution and Environmental Changes (cE3c) / Azorean Biodiversity Group and Universidade dos Açores, Departamento de Ciências e Engenharia do Ambiente, Açores, S.J.N. received funding from the Portuguese National Funds, through Fundação para a Ciência e a Tecnologia (FCT), within the project UID/BIA/00329/2013 and the Research Fellowship PD/BD/114380/2016. S.P.A. acknowledges his research contract (IF/00465/2015) funded by the Portuguese Science Foundation (FCT). C.S.M. is benefiting from a PhD grant M3.1.a/F/100/2015 from FRCT/Açores 2020 by Fundo Regional para a Ciência e Tecnologia (FRCT). Financial support to R.A. was received from the Laboratory of Excellence ‘TULIP’ (PIA-10-LABX-41). This work was supported by FEDER funds through the Operational Programme for Competitiveness Factors – COMPETE and by National Funds through FCT under the UID/BIA/50027/2013, POCI-01-0145-FEDER-006821 and under DRCT-M1.1.a/005/Funcionamento-C-/2016 (CIBIO-A) project from FRCT. This work was also supported by FEDER funds (in 85%) and by funds of the Regional Government of the Azores (15%) through Programa Operacional Açores 2020, in the scope of the project 'AZORESBIOPORTAL – PORBIOTA': ACORES‐01‐0145-FEDER-000072., ANR-11-IDEX-0002,UNITI,Université Fédérale de Toulouse(2011), Repositório da Universidade de Lisboa, Theoretical and Computational Ecology (IBED, FNWI), and IBED (FNWI)
Subjects: general dynamic theory, lava deltas, Biogeography, [SDE.MCG]Environmental Sciences/Global Changes, equilibrium theory, Volcanism, Surface area, [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, volcanic oceanic islands, 14. Life underwater, [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology, Ecology, Evolution, Behavior and Systematics, Sea level, Azores, Global and Planetary Change, geography, geography.geographical_feature_category, Ecology, island biogeography, [SDV.BID.EVO]Life Sciences [q-bio]/Biodiversity/Populations and Evolution [q-bio.PE], Biota, 15. Life on land, species pump theory, Volcano, 13. Climate action, glacial sensitive theory, Species richness, Physical geography, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, [SDV.EE.BIO]Life Sciences [q-bio]/Ecology, environment/Bioclimatology, Volcanic cone, sea level change, Geology
Abstract: Ongoing work shows that species richness patterns on volcanic oceanic islands are shaped by surface area changes driven by longer time scale (>1 ka) geological processes and natural sea level fluctuations. A key question is: what are the rates and magnitudes of the forces driving spatial changes on volcanic oceanic islands which in turn affect evolutionary and biogeographic processes? We quantified the rates of surface-area changes of a whole island resulting from both volcanogenic flows and sea level change over the last glacial-interglacial (GI) cycle (120 ka) for the volcanically active island of Terceira, (Azores, Macaronesia, Portugal). Volcanogenic activity led to incidental but long-lasting surface area expansions by the formation of a new volcanic cone and lava-deltas, whereas sea level changes led to both contractions and expansions of area. The total surface area of Terceira decreased by as much as 24% per time step due to changing sea levels and increased by 37% per time step due to volcanism per time step of 10 ka. However, while sea levels nearly continuously changed the total surface area, volcanic activity only impacted total surface area during two time steps over the past 120 ka. The surface area of the coastal and lowland region (here defined as area
Published: 2020
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41. Etablishing the first continuous Holocene tephrostratigraphy on Kerguelen Archipelago, subantarctic Indian Oean

Author: Eivind Støren, Stéphane Guédron, Bertrand Moine, Anouk Leloup, Nathalie Vanderputten, Jérôme Poulenard, Anne-Lise Develle, Elisabeth Michel, Pierre Sabatier, Emmanuel Malet, Fabien Arnaud, Nicolas Le Viavan, Bernard Fanget, Jacques-Louis de Beaulieu, Jean-Louis Reyss, Marc De Batist, Vincent Perrot, Jostein Bakke, Katrien Heirman, Aymerick Servettaz, 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), 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), Laboratoire Magmas et Volcans (LMV), Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre (ISTerre), 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 Gustave Eiffel-Université Grenoble Alpes (UGA), Department of Earth Science and Bjerknes Centre for Climate Research, University of Bergen, Allégaten 41, 5007 Bergen, Norway, L'Institut polaire français Paul-Emile Victor (IPEV), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), Universiteit Gent = Ghent University (UGENT), 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), 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]), 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 Jean Monnet [Saint-Étienne] (UJM)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Renard Centre of Marine Geology, Department of Geology and Soil Sciences, Ghent University, Krijgslaan 281 S8, B-9000 Ghent, Belgium
Subjects: geography, Paleontology, geography.geographical_feature_category, Volcano, Outcrop, [SDE]Environmental Sciences, Archipelago, Sediment, Glacial period, Chronostratigraphy, Geology, Holocene, Chronology
Abstract: Here we present the first Holocene-long continuous chronology of volcanic eruptions on Kerguelen archipelago, where no evidence of Holocene volcanic activity has been published so far. Our chronicle is based upon sedimentological, chronological and geochemical data form two sediment cores, taken in two different depocenters of a large lake, Lake Armor, located ca. 70 km away from the archipelago’s potentially active volcanic area. This allowed us to confidently attribute the origin of pumice-rich or ash-rich layers to contemporaneous volcanic eruptions. Altogther eight main eruptions, as well as three secondary ones, were here documented and dated, among which the youngest occurred during the Middle Age, between 890 and 980 AD. The oldest eruption is also by far the strongest one and deposited more than 1.2m of up-to 3cm large pumices, 70 km away from the volcanic edifice. It occurred at the very beginnning of the Holocene (11 ka cal. BP), suggesting a climatic control after glacial retreat upon volcanic activity. Additionnal evidences from lake sediment and geological outcrops, both close to Lake Armor and in remote areas over Kerguelen mainland, open the future possibility of a better reconstruction of major eruptions deposit spreading and thus an assessment of their intensity. This established chronostratigraphy will be useful to synchronise paleoenvironment record at least at the scale of the archipelago as well as in surrounding marine areas where Holocene climate reconstructions are particularly sparse.
Published: 2020
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42. Deciphering fluid flow at the magmatic-hydrothermal transition: A case study from the world-class Panasqueira W–Sn–(Cu) ore deposit (Portugal)

Author: Eric Gloaguen, Filipe Pinto, Stanislas Sizaret, Gaëtan Launay, Laurent Guillou-Frottier, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Métallogénie - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Beralt Tin & Wolfram, Geology Department, Universidade do Porto, This research took part in the ERAMIN project 'New Ores' and was financially supported by the French Geological Survey (BRGM) (RP18DGR001), the Region Centre (101985), and the Labex Voltaire (ANR-10-LABX-100-01)., and ANR-10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010)
Subjects: Wolframite, Mineralization (geology), 010504 meteorology & atmospheric sciences, Tourmaline, Geochemistry, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Hydrothermal circulation, Geophysics, Space and Planetary Science, Geochemistry and Petrology, Greisen, Panasqueira, Earth and Planetary Sciences (miscellaneous), engineering, Metasomatism, Vein (geology), [SDU.STU.AG]Sciences of the Universe [physics]/Earth Sciences/Applied geology, ComputingMilieux_MISCELLANEOUS, Geology, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy, 0105 earth and related environmental sciences
Abstract: Deciphering the behavior of fluid flow at the magmatic-hydrothermal transition is crucial to understanding the physical processes leading to the formation of intrusion-related ore deposits and hence to predicting the locations of mineralized bodies. However, the hydrodynamics (direction and velocity) of the hydrothermal fluid flows related to this transitional stage remains poorly constrained. Here we present a coupled textural and chemical study performed on tourmaline growth bands to constrain fluid flow during the initiation of the hydrothermal system of the Panasqueira W–Sn–(Cu) deposit. This exceptional deposit consists of a dense network of flat wolframite and cassiterite-bearing quartz veins intensely developed above a well-known but hidden greisen cupola. The W–Sn mineralization is preceded by a tourmalinization stage occurring as metasomatic halos around veins and as selvages developed along the vein–wall-rocks contacts. Results emphasize the key role of the greisen cupola in fluid focusing and the role of fluid overpressure during vein opening. Velocity values highlight an efficient transport of metals in veins largely dominated by advective processes (10−4 to 10−3 m s−1), whereas fluid flow in the altered wall-rocks is slow and pervasive (10−6 to 10−5 m s−1), suggesting that element transport through the metasedimentary host rock was low and limited to the alteration haloes. LA-ICP-MS analyses of tourmaline growth bands reveal that fluids coming from the cupola are enriched in Na, K, Li, Sr and Sn, emphasizing the contribution of magmatic fluids during vein formation and the metasomatic alteration of the wall-rocks. More generally, this study demonstrates that the apical portions of granite bodies act as emanative centers of mineralizing fluids, and highlights the usefulness of mineral growth band analysis in the search for intrusion-related mineralization.
Published: 2018
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43. Genetic diversity and phylogeography of the elusive, but epidemiologically importantEchinococcus granulosussensu stricto genotype G3

Author: Houria Zait, Teivi Laurimäe, Sami Simsek, Mohammad Rostami-Nejad, Adriano Casulli, Urmas Saarma, Liina Kinkar, Hossein Mirhendi, Eshrat Beigom Kia, Malik Irshadullah, Steffen Rehbein, Viliam Šnábel, Ibrahim Balkaya, Gérald Umhang, Mitra Sharbatkhori, Antonio Varcasia, Francisco Ponce-Gordo, Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia, University of Tartu, Atatürk University School of Medicine, World Health Organization Collaborating Centre for the Epidemiology, Detection and Control of Cystic and Alveolar Echinococcosis, University Hospital Mustapha Alger, Aligarh Muslim University, Golestan University of Medical Sciences, Isfahan University of Medical Sciences, Isfahan University of Medical Sciences [Iran] (MUI), Shahid Beheshti University of Medical Sciences [Tehran] (SBUMS), Shahid Beheshti University, Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), Merial GmbH, Tehran University of Medical Sciences (TUMS), Firat University Faculty of Engineering Geology Department, Slovak Academy of Sciences (SAS), Laboratoire de la rage et de la faune sauvage de Nancy (LRFSN), Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (ANSES), and University of Sassari
Subjects: 0301 basic medicine, Mitochondrial DNA, Species complex, Genotype, [SDV]Life Sciences [q-bio], DNA, Mitochondrial, 03 medical and health sciences, Mitochondrial genome, Sensu, Echinococcosis, Zoonoses, parasitic diseases, Genetic variation, Animals, Humans, [SDV.MP.PAR]Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology, Genetic variability, Echinococcus granulosus, Phylogeny, Genetic diversity, biology, Genotype G3, Genetic Variation, Bayes Theorem, Bayesian phylogeny, DNA, Helminth, biology.organism_classification, 3. Good health, Cystic echinococcosis, Phylogeography, 030104 developmental biology, Infectious Diseases, Evolutionary biology, Genome, Mitochondrial, [SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie, Animal Science and Zoology, Parasitology
Abstract: Cystic echinococcosis (CE) is a severe parasitic disease caused by the species complexEchinococcus granulosussensu lato. Human infections are most commonly associated withE. granulosussensu stricto (s.s.), comprising genotypes G1 and G3. The objective of the current study was to provide first insight into the genetic diversity and phylogeography of genotype G3. Despite the epidemiological importance of the genotype, it has remained poorly explored due to the ambiguity in the definition of the genotype. However, it was recently demonstrated that long sequences of mitochondrial DNA (mtDNA) provide a reliable method to discriminate G1 and G3 from each other. Therefore, we sequenced near-complete mtDNA of 39 G3 samples, covering most of the known distribution range and host spectra of the genotype. The phylogenetic network revealed high genetic variation withinE. granulosus s.s.G3 and while G3 is significantly less prevalent worldwide than G1, the genetic diversity of both of the genotypes is equally high. We also present the results of the Bayesian phylogeographic analysis, which yielded several well-supported diffusion routes of genotype G3 originating from Turkey and Iran, suggesting the Middle East as the origin of the genotype.
Published: 2018
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44. Controls over δ44/40Ca and Sr/Ca variations in coccoliths: New perspectives from laboratory cultures and cellular models

Author: Luz María Mejía, Ana Kolevica, Anton Eisenhauer, Lorena Abrevaya, Clara T Bolton, Ana Mendez-Vicente, Adina Paytan, Florian Böhm, Heather Stoll, Kirsten Isensee, Department of Geological Sciences [Stanford] (GS), Stanford EARTH, Stanford University-Stanford University, Geology Department, and Oviedo University
Subjects: 010504 meteorology & atmospheric sciences, [SDE.MCG]Environmental Sciences/Global Changes, Fractionation, 010502 geochemistry & geophysics, 01 natural sciences, Coccolith, Isotopes of calcium, Paleontology, chemistry.chemical_compound, Geochemistry and Petrology, Earth and Planetary Sciences (miscellaneous), 14. Life underwater, Gephyrocapsa oceanica, skin and connective tissue diseases, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Emiliania huxleyi, biology, biology.organism_classification, Retention efficiency, Geophysics, chemistry, 13. Climate action, Space and Planetary Science, Environmental chemistry, [SDE]Environmental Sciences, Carbonate, Seawater, sense organs, Geology
Abstract: Coccoliths comprise a major fraction of the global carbonate sink. Therefore, changes in coccolithophores' Ca isotopic fractionation could affect seawater Ca isotopic composition, affecting interpretations of the global Ca cycle and related changes in seawater chemistry and climate. Despite this, a quantitative interpretation of coccolith Ca isotopic fractionation and a clear understanding of the mechanisms driving it are not yet available. Here, we address this gap in knowledge by developing a simple model (CaSri–Co) to track coccolith Ca isotopic fractionation during cellular Ca uptake and allocation to calcification. We then apply it to published and new δ44/40Ca and Sr/Ca data of cultured coccolithophores of the species Emiliania huxleyi and Gephyrocapsa oceanica. We identify changes in calcification rates, Ca retention efficiency and solvation–desolvation rates as major drivers of the Ca isotopic fractionation and Sr/Ca variations observed in cultures. Higher calcification rates, higher Ca retention efficiencies and lower solvation–desolvation rates increase both coccolith Ca isotopic fractionation and Sr/Ca. Coccolith Ca isotopic fractionation is most sensitive to changes in solvation–desolvation rates. Changes in Ca retention efficiency may be a major driver of coccolith Sr/Ca variations in cultures. We suggest that substantial changes in the water structure strength caused by past changes in temperature could have induced significant changes in coccolithophores' Ca isotopic fractionation, potentially having some influence on seawater Ca isotopic composition. We also suggest a potential effect on Ca isotopic fractionation via modification of the solvation environment through cellular exudates, a hypothesis that remains to be tested.
Published: 2018
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45. A diatom record of CO2 decline since the late Miocene

Author: Ana Mendez-Vicente, Clara T Bolton, Caroline Ladlow, Heather Stoll, Lorena Abrevaya, Kira T Lawrence, Luz María Mejía, Isabel Cacho, Geology Department, and Oviedo University
Subjects: Alkenone, 010504 meteorology & atmospheric sciences, biology, [SDE.MCG]Environmental Sciences/Global Changes, Fractionation, Forcing (mathematics), 010502 geochemistry & geophysics, biology.organism_classification, 01 natural sciences, Coccolith, Sea surface temperature, Geophysics, Diatom, Oceanography, Productivity (ecology), 13. Climate action, Space and Planetary Science, Geochemistry and Petrology, Isotopes of carbon, [SDE]Environmental Sciences, Earth and Planetary Sciences (miscellaneous), 14. Life underwater, ComputingMilieux_MISCELLANEOUS, Geology, 0105 earth and related environmental sciences
Abstract: Extratropical sea surface temperature records from alkenones record a dramatic cooling of up to 17 °C over the last ∼14 Ma, but the relationship between this cooling and greenhouse gas forcing has been elusive due to sparse and contrasting reconstructions of atmospheric CO2 for the time period. Alkenone carbon isotopic fractionation during photosynthesis has previously been used to estimate changes in pCO2 over this interval, but is complicated by significant changes in cell size of the alkenone-producing coccolithophorids over this time period. In this study, we reconstruct carbon isotopic fractionation during photosynthesis ( e p ) using organic compounds trapped within the frustules of pennate diatoms in sediments from the Eastern Equatorial Pacific Ocean at Ocean Drilling Program Site 846 over the last ∼13 Ma. Physical separation of pennate diatoms prior to measuring carbon isotopic fractionation enables us to obtain a record with constant cell geometry, eliminating this factor of uncertainty in our pCO2 reconstruction. In the past ∼11 Ma, e p declines from 15.5 to 10.3‰. Using the classic diffusive model and taking into account variations in opal content, alkenone concentration and coccolith Sr/Ca as indicators of past productivity and growth rate, and sea surface temperature records from the site, we estimate a decline in pCO2 from 454 ( + / − 41 ) to 250 ( + / − 15 ) ppmv between ∼11 and 6 Ma. Models accounting for changing the significance of active carbon uptake for photosynthesis, which likely produce more accurate CO2 estimates, suggest a significant larger pCO2 decline of up to twice that shown by the classic diffusive model (in average from 794 ( + / − 233 ) ppmv at ∼11 Ma to 288 (+/−25) ppmv at ∼6 Ma, considering growth rates varying between 0.5 and 1.7 day−1). Large uncertainties in the pCO2 estimated between ∼8 and 11 Ma using the active uptake model are related to the growth rate used for calculations. Together, these results suggest CO2 forcing for this period of steep decline in temperatures.
Published: 2017
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46. Mineralogical and geochemical features of the Allan Hills tephra, South Victoria Land: Implications for mid-Pleistocene volcanic activity in Antarctica

Author: Anastassia Y. Borisova, Klaus Peter Jochum, Sophie Gouy, Geology Department, Moscow State University, Moscow 119992, Géosciences Environnement Toulouse (GET), 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), 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), 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: 0106 biological sciences, 010504 meteorology & atmospheric sciences, Geochemistry, Aquatic Science, 01 natural sciences, Mantle (geology), Mantle plume, Oceanic crust, Tephra, Ecology, Evolution, Behavior and Systematics, Amphibole, 0105 earth and related environmental sciences, geography, Explosive eruption, geography.geographical_feature_category, Ecology, 010604 marine biology & hydrobiology, Crust, Pleistocene, Volcano, Allan Hills, 13. Climate action, [SDU]Sciences of the Universe [physics], [SDE]Environmental Sciences, General Earth and Planetary Sciences, Antarctica, Volcanic tephra
Abstract: International audience; More than 100 volcanoes have been discovered in Antarctica, however, the sources of many Antarctic tephras are not yet constrained. In this study, four tephra samples recovered from the environment of Site 27 on an area of blue ice at Allan Hills, South Victoria Land, provide information on magma and crustal sources for the tephra erupted in Antarctica. We report data on the chemistry of Antarctic tephra glasses and minerals analysed by electron microscopy, electron probe microanalysis and laser ablation inductively coupled plasma mass spec-trometry. The tephra amphibole chemistry indicates magma residence at ~1 GPa and ~1100 °C. Abundant Ca-Al-Si-rich minerals imply that the magma ascended from a reservoir at 29.4 +/- 2.7 km depth was affected by the assimilation of calc-silicate crust. The high Fe and Ti contents in the magmatic minerals and the trace element patterns of the glasses typical of a hydrothermally altered oceanic crust suggest that the Allan Hills tephra originated from a mantle plume-derived magma. The fragmented morphology of the glasses implies that the magmatic activity was associated with explosive eruptions during the mid-Pleistocene. The chemistry of the glasses and the presence of rh€ onite and Al-rich spinel minerals suggest that the magma might be genetically related to the currently active McMurdo volcanic group.
Published: 2020
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47. Thermoluminescence of β-particle induced Bern-4M muscovite

Author: Sümeyra Balci-Yegen, Osman Parlak, S. Akça, Mehmet Yüksel, Nurdogan Can, T. Dogan, Mustafa Topaksu, Z.G. Portakal-Uçar, G. Souadi, Physics Department, Cukurova University, Arts-Sciences Faculty, Adana, 01330, Turkey, Cukurova University, Vocational School of Imamoglu, Department of Computer Technologies, Adana, 01700, Turkey, Jazan University, Physics Department, P.O. Box 114, Jazan, 45142, Saudi Arabia, Cukurova University, Engineering Faculty, Geology Department, Adana, 01330, Turkey, and Manisa Celal Bayar University, Department of Physics, Faculty of Arts and Sciences, Muradiye-Manisa, 45010, Turkey
Subjects: Radiation, Materials science, Silicon, 010308 nuclear & particles physics, Magnesium, Sodium, Muscovite, Potassium, Analytical chemistry, chemistry.chemical_element, engineering.material, 01 natural sciences, Thermoluminescence, Oxygen, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, chemistry, Aluminium, 0103 physical sciences, engineering
Abstract: Bern-4M muscovite from Switzerland was investigated via X-ray diffraction (XRD), energy dispersive spectrometer (EDS) and thermoluminescence (TL). Muscovite has the theoretical formula KAl2(AlSi3O10)(FOH)2, or (KF)2(Al2O3)3(SiO2)6(H2O). Chemical analysis of the muscovite sample was carried out using EDS for major oxides. The results indicate that muscovite includes oxygen (59.1%), silicon (18.86%), and aluminum (15.22%) as major elements and contains low concentrations of potassium, magnesium, and sodium. In standard muscovites potassium use to be 10% and oxygen 47%, probably the sample was strongly lixiviated before the analysis. The thermoluminescence spectrum exhibits a wide glow peak located at 250 °C with a shoulder peak at high temperature region. Trap depth and frequency factor were calculated using Hoogenstraaten's method and found to be 1.16 eV and 1.4 × 1010 s−1, respectively. Reproducibility test indicated that the values within ±5% were obtained after 15 cycles. The storage time experiments were performed for different time periods up to 1 week for dark fading. © 2020 Elsevier Ltd
Published: 2020

48. Multi-scale development of a stratiform chromite ore body at the base of the dunitic mantle-crust transition zone (Maqsad diapir, Oman ophiolite): The role of repeated melt and fluid influxes

Author: Nicolas Granier, Anastassia Y. Borisova, Shoji Arai, Mathieu Rospabé, Georges Ceuleneer, 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), 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), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Department of Earth Science [Kanazawa], Kanazawa University (KU), Lomonosov Moscow State University (MSU), 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), Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Brest (UBO), Dynamique terrestre et planétaire (DTP), Université Toulouse III - Paul Sabatier (UT3), 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 de la Recherche Scientifique (CNRS), Geology Department, Moscow State University, Moscow 119992, and Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)
Subjects: 010504 meteorology & atmospheric sciences, [SDU.STU.PE]Sciences of the Universe [physics]/Earth Sciences/Petrography, Geochemistry, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, engineering.material, 010502 geochemistry & geophysics, Ophiolite, Oman ophiolite, 01 natural sciences, chemistry.chemical_compound, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Geochemistry and Petrology, Transition zone, ComputingMilieux_MISCELLANEOUS, Dunitic mantle-crust transition zone, 0105 earth and related environmental sciences, Olivine, Fractional crystallization (geology), Melt hybridization, Chromite, Stratiform chromitite, Geology, Diapir, Silicate, chemistry, [SDU]Sciences of the Universe [physics], engineering, Chromitite, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
Abstract: International audience; A stratiform chromite ore body crops out in the lower part of the dunitic mantle-crust transition zone (DTZ) that developed at the top of a mantle diapir in the Maqsad area in the Oman ophiolite. It is made of layers ranging in thickness from a few mm to a maximum of 3 m, and in modal composition from massive to antinodular and disseminated ore. The ore body is about 50 m thick and its lateral extent does not exceed several hundred meters. The layering dips gently to the southeast, parallel to that of the overlying gabbroic cumulates. The chromite composition is typical of a MORB kindred - moderate XCr (100 x Cr/(Cr + Al) atomic ratio), ranging from 48 to 60, and relatively high TiO2 content, ranging from about 0.3 to 0.5 wt% -, a characteristic shared by most lithologies issued from the igneous activity of the Maqsad diapir. The silicate matrix is essentially made of slightly serpentinized olivine with minor clinopyroxene and rare pargasitic amphibole, orthopyroxene and garnet. This strongly contrasts with the nature of the mineral inclusions mostly made of the assemblage amphibole-orthopyroxene-mica, enclosed in the chromite grains and represented in abundance all along the ore body whatever the ore grade. The inclusions demonstrate the involvement of a silica- and water-rich melt and/or fluid, in addition to MORB, in the early stages of chromite crystallization. The chemical composition of chromite, silicate matrix, together with the one of silicate inclusions display well-defined evolutions vertically along the stratiform chromitite. At the scale of the ore body, the compositional trends are independent of the ore concentration but the major kinks in these trends are well-correlated with levels of magmatic breccias. This shows that abrupt chemical changes can be attributed to sudden melt ± fluids injection events followed mainly by melt-fluid-rock interaction and in a lesser extent by quieter evolution by fractional crystallization. At the thin section scale, second order chemical variations, essentially in the Mg# (100 Mg/(Mg þ Fe2þ) atomic ratio) of chromite and Fo of olivine, are clearly attributable to re-equilibration between these two solid phases, possibly in the presence of an interstitial melt/fluid.
Published: 2019
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49. Global distribution of earthworm diversity

Author: André L.C. Franco, Michiel Rutgers, Miguel Á. Rodríguez, Thomas W. Crowther, Helen Phillips, Tunsisa T. Hurisso, Olaf Schmidt, Matthew W. Warren, Shishir Paudel, Michael B. Wironen, Mónica Gutiérrez López, Basil V. Iannone, Aidan M. Keith, Amy Choi, Esperanza Huerta Lwanga, Boris Schröder, Olga Ferlian, Jaswinder Singh, Javier Rodeiro-Iglesias, Martin Holmstrup, Geoff H. Baker, Yahya Kooch, Rosa Fernández, Konstantin B. Gongalsky, Lindsey Norgrove, Eric Blanchart, Madhav P. Thakur, Felicity Crotty, Steven J. Vanek, Thomas Bolger, Jan Hendrik Moos, Guillaume Xavier Rousseau, Marie Luise Carolina Bartz, Iñigo Virto, Michael Steinwandter, Kelly S. Ramirez, Veikko Huhta, Ulrich Brose, Michel Loreau, Davorka K. Hackenberger, David J. Russell, Loes van Schaik, Salvador Rebollo, Jonatan Klaminder, Gerardo Moreno, Benjamin Schwarz, Julia Seeber, Yvan Capowiez, David A. Wardle, Bernd Blossey, Franciska T. de Vries, Christoph Emmerling, Robert L. Bradley, Courtland Kelly, Liliana B. Falco, Alexander M. Roth, Michael J. Gundale, Radim Matula, Andrea Dávalos, Lorenzo Pérez-Camacho, Johan Neirynck, Monika Joschko, Marta Novo, Dolores Trigo, Jérôme Mathieu, Adrian A. Wackett, Anne W. de Valença, Elizabeth M. Bach, Daniel R. Lammel, Devin Routh, Madalina Iordache, Luis M. Hernández, Johan Pansu, Juan B. Jesús Lidón, Alejandro Morón-Ríos, Maxim Shashkov, Ehsan Sayad, Martine Fugère, Nobuhiro Kaneko, Mark E. Caulfield, Klaus Birkhofer, Wim H. van der Putten, Iurii M. Lebedev, Alberto Orgiazzi, Miwa Arai, H. Lalthanzara, Raphaël Marichal, Andrew R. Holdsworth, Steven J. Fonte, Maria J. I. Briones, Raúl Piñeiro, Jean-François Ponge, Nick van Eekeren, Takuo Hishi, Julia Krebs, Joanne M. Bennett, George G. Brown, Birgitta König-Ries, Carlos Fragoso, Victoria Nuzzo, Anna Rożen, Scott R. Loss, Bart Muys, Bryant C. Scharenbroch, Michael Schirrmann, Radoslava Kanianska, Irina V. Zenkova, Maria Kernecker, Abegail T Fusilero, Sandy M. Smith, Shaieste Gholami, Robin Beauséjour, Mac A. Callaham, Nathaniel H. Wehr, Yiqing Li, Kristine N. Hopfensperger, Mujeeb Rahman P, Andrés Esteban Duhour, Erin K. Cameron, Diana H. Wall, Muhammad Rashid, José Antonio Talavera, Matthias C. Rillig, Armand W. Koné, Johan van den Hoogen, Darío J. Díaz Cosín, Anahí Domínguez, Thibaud Decaëns, Fredrick O. Ayuke, Carlos A. Guerra, Guénola Pérès, Volkmar Wolters, Jiro Tsukamoto, Nico Eisenhauer, José Camilo Bedano, Weixin Zhang, Noa Kekuewa Lincoln, Visa Nuutinen, Joann K. Whalen, Christian Mulder, Sanna T. Kukkonen, German Centre for Integrative Biodiversity Research (iDiv), Universidade Positivo, Departamento de Ecología y Biología Animal, Universidad de Vigo, Crowther Lab, Institute of Integrative Biology, ETH Zürich, A.N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences [Moscow] (RAS), JRC Institute for Environment and Sustainability (IES), European Commission - Joint Research Centre [Ispra] (JRC), Department of Biology [Fort Collins], Colorado State University [Fort Collins] (CSU), German Centre for Integrative Biodiversity Research, Étude et compréhension de la biodiversité (ECODIV), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU), Friedrich-Schiller-Universität Jena, Station d'écologie théorique et expérimentale (SETE), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut d'écologie et des sciences de l'environnement de Paris (IEES), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Recherche Agronomique (INRA), Department of Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), National Institute for Public Health and the Environment [Bilthoven] (RIVM), Institut de recherche pour le développement [IRD] : UMR210, School of Biology and Environmental Science, University College Dublin [Dublin] (UCD), Unité de recherche Plantes et Systèmes de Culture Horticoles (PSH), Institut National de la Recherche Agronomique (INRA), Centro International de Agricultura Tropical, Red de Biodiversidad y Sistemática, Instituto de Ecología, Department of Terrestrial Ecology, Fluides, automatique, systèmes thermiques (FAST), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Biogéochimie et écologie des milieux continentaux (Bioemco), Centre National de la Recherche Scientifique (CNRS)-AgroParisTech-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Recherche Agronomique (INRA)-École normale supérieure - Paris (ENS Paris), Universidad de Extremadura (UEX), Division of Forest, Nature and Landscape, Department of Earth and Environmental Sciences [Leuven] (EES), Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven)-Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Laboratoire d'Ecologie Alpine (LECA), Université Grenoble Alpes (UGA)-Université Joseph Fourier - Grenoble 1 (UJF)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Sol Agro et hydrosystème Spatialisation (SAS), AGROCAMPUS OUEST-Institut National de la Recherche Agronomique (INRA), University of Vigo [ Pontevedra], Centre d'Ecologie et des Sciences de la COnservation (CESCO), Muséum national d'Histoire naturelle (MNHN)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Center of Excellence in Environmental Studies, King Abdulaziz University, Dept Ciencias Vida, Universidad de Alcalá - University of Alcalá (UAH), Faculty of Business Administration and Economics, DS&OR-Lab, University of Paderborn, Laboratoire d'oncogénétique moléculaire, Mountain Agriculture Research Unit, University of Innsbruck, Independent, Universidad Pública de Navarra [Espagne] (UPNA), McGill University, Department of Animal Ecology and Systematics, Justus-Liebig-Universität Gießen (JLU), Jiangsu Academy of Agricultural Sciences, Université de Leipzig, Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Leipzig University, Martin-Luther-Universität Halle Wittenberg (MLU), Universidade de Vigo, Embrapa Forestry, Brazilian Agricultural Research Corporation (Embrapa), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), M.V. Lomonosov Moscow State University, Department of Biometry and Environmental System Analysis, Albert-Ludwigs-Universität Freiburg, Institute of Biodiversity, Friedrich Schiller University Jena, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institute of Computer Science, Friedrich Schiller University Jena, Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-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), Institut d'écologie et des sciences de l'environnement de Paris (iEES), Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Università degli studi di Catania = University of Catania (Unict), Department of Terrestrial Ecology [Wageningen], Netherlands Institute of Ecology (NIOO-KNAW), Laboratory of Nematology, Department of Plant Sciences, Wageningen University & Research, Freie Universität Berlin, Senckenberg Museum of Natural History Görlitz, Senckenberg – Leibniz Institution for Biodiversity and Earth System Research - Senckenberg Gesellschaft für Naturforschung, Leibniz Association-Leibniz Association, Global Soil Biodiversity Initiative and School of Global Environmental Sustainability, Colorado State University, Asian School of the Environment (ASE), Nanyang Technological University [Singapour], Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization, Department of Land Resource Management and Agricultural technology (LARMAT), College of 80 Agriculture and Veterinary Sciences, University of Nairobi (LARMAT), CSIRO Health & Biosecurity, Département de biologie [Sherbrooke] (UdeS), Faculté des sciences [Sherbrooke] (UdeS), Université de Sherbrooke (UdeS)-Université de Sherbrooke (UdeS), Geology Department, FCEFQyN, ICBIA-CONICET (National Scientific and Technical Research Council), National University of Río Cuarto, Department of Ecology, Brandenburg University of Technology, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Department of Natural Resources, Cornell University, Cornell University [New York], UCD Earth Institute, University College Dublin, USDA Forest Service, Southern Research Station, Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH), Institut National de la Recherche Agronomique (INRA)-Avignon Université (AU), Farming Systems Ecology, Wageningen University and Research, Faculty of Forestry, University of Toronto, Institute of Biological, Environmental & Rural Sciences, Aberystwyth University, Department of Biological Sciences, SUNY Cortland, Department of Biodiversity, Ecology and Evolution [Madrid], Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), Laboratorio de Ecología, Instituto de Ecología y Desarrollo Sustentable, Universidad Nacional de Luján, Louis Bolk Institute (LBI), Department of Soil Science, Faculty of Regional & Environmental Sciences, University of Trier, Ciencias Básicas, Instituto de Ecología y Desarrollo Sustentable -INEDES, Universidad Nacional de Lujan, Institut de Biologia Evolutiva [Barcelona] (IBE / UPF - CSIC), Universitat Pompeu Fabra [Barcelona] (UPF), Department of Soil and Crop Sciences, Colorado State University, Biodiversity and Systematic Network, Instituto de Ecología A.C., Department of Biological Science and Environmental Studies, University of the Philippines - Mindanao, Natural Resources Department, Razi University, Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Department of Biology, J. J. Strossmayer University of Osijek, Agricultural Engineering, Postgraduate Program in Agroecology, Maranhão State University, Faculty of Agriculture, Kyushu University, Minnesota Pollution Control Agency, Department of Bioscience, Aarhus University, Biological Sciences, Northern Kentucky University, Agricultura Sociedad y Ambiente, El Colegio de la Frontera Sur, Soil Physics and Land Management degradation, Wageningen University & Research, Wageningen University, Department of Biological and Environmental Science [Jyväskylä Univ] (JYU), University of Jyväskylä (JYU), College of Agriculture, Environmental and Human Sciences, Lincoln University of Missouri, School of Forest Resources and Conservation [Gainesville] (UF|IFAS|FFGS), Institute of Food and Agricultural Sciences [Gainesville] (UF|IFAS), University of Florida [Gainesville] (UF)-University of Florida [Gainesville] (UF), Sustainable Development and Environment Engineering, Banat's University of Agricultural Sciences and Veterinary Medicine 'King Michael the 1st of Romania', Experimental Infrastructure Platform, Leibniz Centre for Agricultural Landscape Research (ZALF), Faculty of Food and Agricultural Sciences, Fukushima University, Matej Bel University (UMB), Centre for Ecology and Hydrology [Lancaster] (CEH), Natural Environment Research Council (NERC), Land Use and Governance, Leibniz Centre for Agricultural Landscape Research (ZALF), Climate Impacts Research Centre (CIRC), Umeå University, UR Gestion Durable des Sols, UFR Sciences de la Nature, Université Nangui Abrogoua, Tarbiat Modares University [Tehran], Natural Resources Institute Finland (LUKE), Department of Zoology, Pachhunga University College, Soil Science, ESALQ-USP, Universidade de São Paulo, College of Agriculture, Forestry and Natural Resource Management, University of Hawaii at Hilo, Tropical Plant and Soil Sciences, College of Tropical Agriculture and Human Resources, University of Hawai‘i at Mānoa, Department of Natural Resource Ecology and Management, Oklahoma State University, Performance des systèmes de culture des plantes pérennes (UPR Système de pérennes), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague (CZU), Department of Soil and Environment, Forest Research Institute of Baden-Wuerttemberg, Thuenen-Institute of Organic Farming, Forestry School - INDEHESA, University of Extremadura, Conservación de la Biodiversidad, El Colegio de la Frontera Sur, Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Research Institute for Nature and Forest, Research Institute for Nature and Forest (INBO), School of Agricultural, Forest and Food Sciences, Bern University of Applied Sciences (BFH), Natural Area Consultants, Department of Zoology, Pocker Sahib Memorial Orphanage College, CSIRO Ocean & Atmosphere, CSIRO, Adaptation et diversité en milieu marin (AD2M), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Station biologique de Roscoff (SBR), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Ecology and Forest Restoration Group, Department of Life Sciences, University of Alcalá, Computing, ESEI, Vigo, Mécanismes Adaptatifs et Evolution (MECADEV), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Centre of Excellence in Environmental Studies, King Abdulaziz University, Environmental Sciences, COMSATS University, Life Sciences, Sciences Faculty, University of Alcalá, University of Minnesota [Twin Cities] (UMN), University of Minnesota System, Friends of the Mississippi River, Postgraduate Program in Biodiversity and Conservation, Federal University of Maranhão, Uniwersytet Jagielloński w Krakowie = Jagiellonian University (UJ), Institute of Ecology, Technical University of Berlin, College of Natural Resources, University of Wisconsin, Engineering for Crop Production, Leibniz Institute for Agricultural Engineering and Bioeconomy (ATB), UCD School of Agriculture and Food Science, University College Dublin, Landscape Ecology and Environmental Systems Analysis, Institute of Geoecology, Technische Universität Braunschweig, Universität Innsbruck [Innsbruck], Institute for Alpine Environment, Eurac Research, Laboratory of Ecosystem Modelling, Institute of Physicochemical and Biological Problems in Soil Sciences, Russian Academy of Science, Laboratory of Computational Ecology, Institute of Mathematical Problems of Biology RAS – the Branch of Keldysh Institute of Applied Mathematics of Russian Academy of Sciences, Post Graduate Department of Zoology, Khalsa College Amritsar, John H. Daniels Faculty of Architecture, Landscape and Design, University of Toronto, Universidad de La Laguna [Tenerife - SP] (ULL), Faculty of Agriculture, Kochi University, Food & Agriculture, WWF-Netherlands, Universidad Pública de Navarra [Espagne] = Public University of Navarra (UPNA), Soil, Water and Climate, University of Minnesota, Earth Innovation Institute, Department of Natural Resources & Environmental Management, University of Hawai'i at Mānoa, Natural Resource Sciences, McGill University, McGill University = Université McGill [Montréal, Canada], The Nature Conservancy, Justus-Liebig-Universität Gießen = Justus Liebig University (JLU), Laboratory of Terrestrial Ecosystems, Kola Science Centre, Institute of the North Industrial Ecology Problems, Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions (Henan University), Ministry of Education, College of Environment and Planning, Henan University, Department of Environmental Science, Saint Mary’s University, Faculty of Biological and Environmental Sciences [Helsinki], Helsingin yliopisto = Helsingfors universitet = University of Helsinki, ANR-11-IDEX-0002,UNITI,Université Fédérale de Toulouse(2011), Institute of Biology, Leipzig University, Institute of Biology, Martin Luther University Halle-Wittenberg, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud]), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (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), Department of Biological, Geological and Environmental Sciences, University of Catania, Institute of Biology, Freie Universität Berlin, Senckenberg Museum for Natural History Görlitz, Department of Soil Zoology, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Faculty of Natural Resources & Marine Sciences, Tarbiat Modares University, Production Systems, Horticulture Technologies, Natural Resources Institute Finland, Soil Ecosystems, Natural Resources Institute Finland (Luke), Station biologique de Roscoff (SBR), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de la Recherche Agronomique (INRA), Departamento de Informática, Escuela Superior de Ingeniería Informática, Universidad de Vigo, Institute of Environmental Sciences, Jagiellonian University, Department of Ecology, University of Innsbruck, Department of Animal Biology (Zoology area), Science Faculty, University of La Laguna, Dpto. Ciencias, IS-FOOD, Universidad Pública de Navarra, Department of Animal Ecology, Justus Liebig University, University of Helsinki, German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Department of Biology, Colorado State University, Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Université Joseph Fourier - Grenoble 1 (UJF)-Université Grenoble Alpes (UGA), Lomonosov Moscow State University (MSU), Friedrich-Schiller-Universität = Friedrich Schiller University Jena [Jena, Germany], Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université de Toulouse (UT)-Université de Toulouse (UT)-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), Wageningen University and Research [Wageningen] (WUR), National Agriculture and Food Research Organization (NARO), University of Nairobi (UoN), Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), National University of Río Cuarto = Universidad Nacional de Río Cuarto (UNRC), Brandenburg University of Technology [Cottbus – Senftenberg] (BTU), Department of Natural Resources & The Environment [CALS], College of Agriculture and Life Sciences [Cornell University] (CALS), Cornell University [New York]-Cornell University [New York], School of Biology and Environmental Sciences (SBES), USDA Forest Service, University of Toronto, Aberystwyth University, Universidad Nacional de Luján [Buenos Aires], Trier University of Applied Sciences, Razi University of Kermanshah, Josip Juraj Strossmayer University of Osijek, Universidade Estadual do Maranhão = State University of Maranhão (UEMA), Kyushu University, Aarhus University [Aarhus], Northern Kentucky University, Adaptation et diversité en milieu marin (ADMM), Institut national des sciences de l'Univers (INSU - CNRS)-Station biologique de Roscoff (SBR), Ecosystem and Landscape Dynamics (IBED, FNWI), Deutsche Forschungsgemeinschaft - German Research Foundation (DFG), Martin-Luther-University Halle-Wittenberg, Joint Research Centre, European Commission, Department of Biology, University of Minho [Braga], University of Amsterdam [Amsterdam] (UvA), Institut d'écologie et des sciences de l'environnement de Paris (iEES Paris), Institut National de la Recherche Agronomique (INRA)-Sorbonne Université (SU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Royal Netherlands Academy of Arts and Sciences (KNAW), Laboratory of Nematology, Department of Plant Sciences, Free University of Berlin (FU), Senckenberg Research Institute, European Project: 227161,EC:FP7:KBBE,FP7-KBBE-2008-2B,BIOBIO(2009), Biometry and Environmental System Analysis, University of Freiburg, Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Paul-Valéry - Montpellier 3 (UM3), Theoretical and Experimental Ecology Station, Centre National de la Recherche Scientifique (CNRS), Asian School of the Environment, Nanyang Technological University, Département de Biologie, Université de Sherbrooke, Sherbrooke, QC, Canada, Université de Sherbrooke, Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Cornell University, UMR 1114 'EMMAH', INRA, Complutense University of Madrid (UCM), Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Forest Ecology and Management, Swedish University of Agricultural Sciences, Department of Biological and Environmental Science, University of Jyväskylä, School of Forest Resources and Conservation, University of Florida, Department of Environmental Management, Faculty of Natural Sciences, Matej Bel University, Department of Ecology and Environmental Science, Climate Impacts Research Centre, Umeå University, A.N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Performance des systèmes de culture des plantes pérennes (Cirad-Persyst-UPR 34 Système de pérennes), Département Performances des systèmes de production et de transformation tropicaux (Cirad-PERSYST), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Department of Earth & Environmental Sciences, KU Leuven, School of Agricultural, Forest and Food Sciences, Bern University of Applied Sciences, UMR7144 Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, CNRS-Sorbonne Universite, AGROCAMPUS OUEST-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Mécanismes adaptatifs : des organismes aux communautés (MECADEV), Department of Forest Resources, University of Minnesota, Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), European Research Council, Academy of Finland, Natural Sciences and Engineering Research Council of Canada, Russian Foundation for Basic Research, Slovak Research and Development Agency, Wageningen University and Research Centre, International Atomic Energy Agency, Fundação de Amparo à Pesquisa do Estado de São Paulo, Royal Canadian Geographical Society, Irish Government, University of Hawaii, U.S. Navy, Department of Science and Technology (India), Department of Defense (US), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Brasil), Ministry of Education, Youth and Sports (Czech Republic), Agence Nationale de la Recherche (France), Austrian Science Fund, Welsh Government, Science Foundation Ireland, University of Kentucky, Higher Education Commission (Pakistan), Universidad Complutense de Madrid, Grains Research and Development Corporation (Australia), Consejo Nacional de Investigaciones Científicas y Técnicas (Argentina), Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brasil), Ministère de l'Europe et des Affaires étrangères (France), University of Minho, Università degli Studi di Catania (UniCT), Terrestrial Ecology (TE), Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)
Subjects: 0106 biological sciences, LITTER, Earth, Planet, Climate, Biologie du sol, Biodiversity, Facteur climatique, 01 natural sciences, Ver de terre, Ecosystem services, purl.org/becyt/ford/1 [https], Soil, Abundance (ecology), FORESTS, 11. Sustainability, DRIVERS, Biomass, 2. Zero hunger, 0303 health sciences, Biomass (ecology), Multidisciplinary, biology, Ecology, Earth, 04 agricultural and veterinary sciences, POPULATION-DENSITY, earthworm, distribution, diversity, pattern, PE&RC, MINHOCAS, Habitat, Plant Production Systems, international, L20 - Écologie animale, Biodiversité, Écosystème, Zone tropicale, Soil biology, Biocénose, Invertebrados, [SDV.SA.SDS]Life Sciences [q-bio]/Agricultural sciences/Soil study, Models, Biological, 010603 evolutionary biology, Ecology and Environment, Zone tempérée, 03 medical and health sciences, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Life Science, Animals, Ecosystem, PLANT, Oligochaeta, purl.org/becyt/ford/1.6 [https], 030304 developmental biology, Earthworm, Tropics, P34 - Biologie du sol, Species diversity, SHIFTS, Farm Systems Ecology Group, Bodemfysica en Landbeheer, 15. Life on land, Ecología, biology.organism_classification, Soil Physics and Land Management, SOIL, Agriculture and Soil Science, 13. Climate action, Plantaardige Productiesystemen, 040103 agronomy & agriculture, PATTERNS, Linear Models, 0401 agriculture, forestry, and fisheries, BIODIVERSITY, Species richness, Planet, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, COMMUNITIES, Zoology, Animal Distribution, Models Biological
Abstract: Soil organisms, including earthworms, are a key component of terrestrial ecosystems. However, little is known about their diversity, their distribution, and the threats affecting them. We compiled a global dataset of sampled earthworm communities from 6928 sites in 57 countries as a basis for predicting patterns in earthworm diversity, abundance, and biomass. We found that local species richness and abundance typically peaked at higher latitudes, displaying patterns opposite to those observed in aboveground organisms. However, high species dissimilarity across tropical locations may cause diversity across the entirety of the tropics to be higher than elsewhere. Climate variables were found to be more important in shaping earthworm communities than soil properties or habitat cover. These findings suggest that climate change may have serious implications for earthworm communities and for the functions they provide., 677232 to N.E.). K.S.R. and W.H.v.d.P. were supported by ERC-ADV grant 323020 to W.H.v.d.P. Also supported by iDiv (DFG FZT118) Flexpool proposal 34600850 (C.A.G. and N.E.); the Academy of Finland (285882) and the Natural Sciences and Engineering Research Council of Canada (postdoctoral fellowship and RGPIN-2019-05758) (E.K.C.); DOB Ecology (T.W.C., J.v.d.H., and D.R.); ERC-AdG 694368 (M.R.); and the TULIP Laboratory of Excellence (ANR-10-LABX-41) (M.L.). In addition, data collection was funded by the Russian Foundation for Basic Research (12-04-01538-a, 12-04-01734-a, 14-44-03666-r_center_a, 15-29-02724-ofi_m, 16-04-01878-a 19-05-00245); Tarbiat Modares University; Aurora Organic Dairy; UGC(NERO) (F. 1-6/Acctt./NERO/2007-08/1485); Natural Sciences and Engineering Research Council (RGPIN-2017-05391); Slovak Research and Development Agency (APVV-0098-12); Science for Global Development through Wageningen University; Norman Borlaug LEAP Programme and International Atomic Energy Agency (IAEA); São Paulo Research Foundation - FAPESP (12/22510-8); Oklahoma Agricultural Experiment Station; INIA - Spanish Agency (SUM 2006-00012-00-0); Royal Canadian Geographical Society; Environmental Protection Agency (Ireland) (2005-S-LS-8); University of Hawai‘i at Mānoa (HAW01127H; HAW01123M); European Union FP7 (FunDivEurope, 265171); U.S. Department of the Navy, Commander Pacific Fleet (W9126G-13-2-0047); Science and Engineering Research Board (SB/SO/AS-030/2013) Department of Science and Technology, New Delhi, India; Strategic Environmental Research and Development Program (SERDP) of the U.S. Department of Defense (RC-1542); Maranhão State Research Foundation (FAPEMA); Coordination for the Improvement of Higher Education Personnel (CAPES); Ministry of Education, Youth and Sports of the Czech Republic (LTT17033); Colorado Wheat Research Foundation; Zone Atelier Alpes, French National Research Agency (ANR-11-BSV7-020-01, ANR-09-STRA-02-01, ANR 06 BIODIV 009-01); Austrian Science Fund (P16027, T441); Landwirtschaftliche Rentenbank Frankfurt am Main; Welsh Government and the European Agricultural Fund for Rural Development (Project Ref. A AAB 62 03 qA731606); SÉPAQ; Ministry of Agriculture and Forestry of Finland; Science Foundation Ireland (EEB0061); University of Toronto (Faculty of Forestry); National Science and Engineering Research Council of Canada; Haliburton Forest and Wildlife Reserve; NKU College of Arts and Sciences Grant; Österreichische Forschungsförderungsgesellschaft (837393 and 837426); Mountain Agriculture Research Unit of the University of Innsbruck; Higher Education Commission of Pakistan; Kerala Forest Research Institute, Peechi, Kerala; UNEP/GEF/TSBF-CIAT Project on Conservation and Sustainable Management of Belowground Biodiversity; Ministry of Agriculture and Forestry of Finland; Complutense University of Madrid/European Union FP7 project BioBio (FPU UCM 613520); GRDC; AWI; LWRRDC; DRDC; CONICET (National Scientific and Technical Research Council) and FONCyT (National Agency of Scientific and Technological Promotion) (PICT, PAE, PIP), Universidad Nacional de Luján y FONCyT [PICT 2293 (2006)], Fonds de recherche sur la nature et les technologies du Québec (131894), Deutsche Forschungsgemeinschaft [SCHR1000/3-1, SCHR1000/6-1, 6-2 (FOR 1598), WO 670/7-1, WO 670/7-2, and SCHA 1719/1-2], CONACYT (FONDOS MIXTOS TABASCO/PROYECTO11316); NSF (DGE-0549245, DGE-0549245, DEB-BE-0909452, NSF1241932); Institute for Environmental Science and Policy at the University of Illinois at Chicago; Dean’s Scholar Program at UIC; Garden Club of America Zone VI Fellowship in Urban Forestry from the Casey Tree Endowment Fund; J. E. Weaver Competitive Grant from the Nebraska Chapter of The Nature Conservancy; the College of Liberal Arts and Sciences at DePaul University; Elmore Hadley Award for Research in Ecology and Evolution from the UIC Dept. of Biological Sciences; Spanish CICYT (AMB96-1161; REN2000-0783/GLO; REN2003-05553/GLO; REN2003-03989/GLO; CGL2007-60661/BOS); Yokohama National University; MEXT KAKENHI (25220104); Japan Society for the Promotion of Science KAKENHI (25281053, 17KT0074, 25252026); ADEME (0775C0035); Ministry of Science, Innovation and Universities of Spain (CGL2017-86926-P); Syngenta Philippines; UPSTREAM; LTSER (Val Mazia/Matschertal); Marie Sklodowska Curie Postdoctoral Fellowship (747607); National Science and Technology Base Resource Survey Project of China (2018FY100306); McKnight Foundation (14-168); Program of Fundamental Researches of Presidium of Russian Academy of Sciences (AAAA-A18-118021490070-5); Brazilian National Council of Research CNPq; and French Ministry of Foreign and European Affairs. Author contributions: H.R.P.P. led the analysis, data curation, and writing of the original manuscript draft. C.A.G. assisted in analyses and writing of the original manuscript draft. E.K.C. and N.E. revised subsequent manuscript drafts. J.v.d.H., D.R., and T.W.C. provided additional analyses. E.K.C., N.E., and M.P.T. acquired funding for the project. J.K., K.B.G., B.S., M.L.C.B., M.J.I.B., and G.B. contributed to data curation. H.R.P.P., C.A.G., M.L.C.B., M.J.I.B., G.B., O.F., A.O., E.M.B., J.B., U.B., T.D., F.T.d.V., B.K.-R., M.L., J.M., C.M., W.H.v.d.P., K.S.R., M.C.R., D.R., M.R., M.P.T., D.H.W., D.A.W., E.K.C., and N.E. contributed to the project conceptualization. All authors reviewed and edited the final draft manuscript. The majority of the authors provided data for the analyses. Competing interests: The authors declare no competing interests. Data and materials availability: Data and analysis code are available on the iDiv Data repository (DOI: 10.25829/idiv.1804-5-2593) and GitHub (https://github.com/helenphillips/GlobalEWDiversity; DOI: 10.5281/zenodo.3386456).
Published: 2019
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50. Contrasting behavior of nitrate and phosphate flux from high flow events on small agricultural and urban watersheds

Author: François Birgand, Soni M. Pradhanang, Sarah L. Frazar, Kelly Addy, Arthur J. Gold, Florentina Moatar, Andrew W. Schroth, D. Q. Kellogg, University of Rhode Island (URI), RiverLy (UR Riverly), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), North Carolina State University [Raleigh] (NC State), University of North Carolina System (UNC), Geology Department, University of Vermont, National Science Foundation (NSF) : IIA-1330406, USDA National Institute of Food and Agriculture, Multistate Hatch 1005742, S-1063, UNIVERSITY OF RHODE ISLAND KINGSTON USA, Partenaires IRSTEA, Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), NORTH CAROLINA STATE UNIVERSITY RALEIGH USA, University of Vermont [Burlington], National Science Foundation (NSF) : IIA-1330406USDA National Institute of Food and Agriculture, Multistate Hatch :1005742 S-1063, and USDA National Institute of Food and Agriculture, Multistate Hatch 1005742 S-1063
Subjects: 010504 meteorology & atmospheric sciences, Storm flow, Phosphate, Nitrate, 01 natural sciences, chemistry.chemical_compound, [SPI]Engineering Sciences [physics], Nutrient flux, Environmental Chemistry, Urban, 0105 earth and related environmental sciences, Earth-Surface Processes, Water Science and Technology, Sensor, Hydrology, Agricultural, Baseflow, First flush, Storm, 04 agricultural and veterinary sciences, 15. Life on land, Watershed, 6. Clean water, Infiltration (hydrology), Wastewater, chemistry, 13. Climate action, [SDU]Sciences of the Universe [physics], [SDE]Environmental Sciences, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Environmental science, Water quality, Surface runoff
Abstract: International audience; Soluble nutrient flux is increasingly implicated in the degradation of receiving water quality. With high-frequency sensors, river discharge along with nitrate and orthophosphate concentrations were collected over 2 years. We examined how storms (16 events) affected the dissolved nutrient flux in two watersheds with contrasting landcover-urban and agricultural. The adjacent watersheds, both < 7 km(2), had very similar soil, slope, relief, and physiography. Wastewater is conveyed outside of the watersheds minimizing this nutrient source. Cumulative nitrate and orthophosphate fluxes in the agricultural watershed were substantially higher than the urban watershed. In both watersheds, a disproportionate amount of discharge, higher orthophosphate concentrations and flux occurred during the highest flow events-approximately 50-70% of flux occurring in the highest 5% of daily discharge. The nitrate flux was dampened compared to discharge during storm events. Baseflow accounted for 66% of the nitrate flux and had higher or comparable concentrations than storm events. The pattern of flux and concentration within storm events also differed for the two solutes. Nitrate exhibited positive hysteresis (higher concentrations on the rising limb of the hydrograph) and magnification of flux during the first flush of storm runoff. In contrast, orthophosphate concentrations were lower on the rising limb and flux during the first flush of storm runoff was dampened. In addition to targeting source reductions, orthophosphate flux may require runoff reducing strategies (i.e., enhanced infiltration) from large runoff events. First flush stormwater management practices combined with enhancement/protection of groundwater nitrate sinks (e.g., riparian wetlands) may help reduce nitrate fluxes.
Published: 2019
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