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Accueil > Recherche > Productions Scientifiques > Articles dans des revues avec comité de lecture

Articles dans des revues avec comité de lecture : Année 2011

Identification of sulfur-cycle prokaryotes in a low-sulfate lake (Lake Pavin) using aprA and 16S rRNA gene markers.

9 juillet 2013

Geochemical researches at Lake Pavin, a low-sulfate-containing freshwater lake, suggest that the dominant biogeochemical processes are iron and sulfate reduction, and methanogenesis. Although the sulfur cycle is one of the main active element cycles in this lake, little is known about the (...)

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Convergent tracer tests in multilayered aquifers: the importance of vertical flow in the injection borehole

11 juin 2013

A mathematical model describing the steady state flows in a forced gradient tracer test between an injection and pumping borehole in a multilayered sandstone aquifer has been developed that includes the effect of vertically variable background heads. A second model describing the recovery of (...)

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Ground Penetrating Radar: Water Table Detection Sensitivity to Soil Water Retention Properties

6 juin 2013

We are interested in Ground Penetrating Radar (GPR) as a geophysical tool useful for determining the depth of the ground water table (GWT) and for monitoring shallow water infiltration in sandy soils. At hydrostatic equilibrium, the water content distribution in a homogeneous unsaturated soil (...)

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Accounting for long alpha-particle stopping distances in (U-Th-Sm)/He geochronology: Refinement of the baseline case

6 juin 2013

This contribution proposes a number of methodological refinements for accounting for ejection of energetic particles, most particularly in the case of long alpha-particle stopping distance effects in (U-Th-Sm)/He thermochronometry. Recent stopping-distance estimates for minerals commonly used (...)

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Mapping of contaminant plumes with geoelectrical methods. A case study in urban context

23 mai 2013

During the past two decades, the diagnosis and monitoring of polluted sites have become more important. Urban sites are particularly difficult to study, because they are contaminated with various pollutants, and there is a large physical and chemical heterogeneity. The heterogeneity comes from (...)

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Capillary rise quantification based on in-situ artificial deuterium peak displacement and laboratory soil characterization

23 mai 2013

In arid environments, water rises from the saturated level of a shallow aquifer to the drying soil surface where evaporation occurs. This process plays important roles in terms of plant survival, salt balance and aquifer budget. A new field quantification method of this capillary rise flow is (...)

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Use of automated recorders (data loggers) in permafrost temperature monitoring

14 mai 2013

The application of automated temperature recorders (temperature data loggers) in thermal monitoring of upper permafrost is examined. Based on the results of 10 years of use of temperature data loggers in Yakutia, the recommendations are provided on the choice and preparation of data loggers for (...)

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Climate and sea-level variations along the northwestern Tethyan margin during the Valanginian C-isotope excursion : mineralogical evidence from the Vocontian Basin (SE France)

12 septembre 2012

A high resolution mineralogical study (bulk-rock and clay-fraction) was carried out upon the hemipelagic strata of the Angles section (Vocontian Basin, SE France) in which the Valanginian positive C-isotope excursion occurs. To investigate sea-level fluctuations and climate change respectively, (...)

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New U-Pb (ID-TIMS and LA-ICPMS) and 40Ar/39Ar geochronological constraints of the Cretaceous geologic time scale calibration from Hokkaido (Japan).

25 août 2012

We present new radiometric ages in order to constrain the calibration of the Cretaceous time scale. They have been obtained from volcanic tuffs sampled at Hokkaido (Japan) within the Northwest Pacific marine succession of the Yezo Group, and are compared with ages from the Western Interior and (...)

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Isotopes and groundwater management strategies under semi-arid area: Case of theSouss upstream basin (Morocco)

13 avril 2012

This study concerns the Souss upstream basin. The objective is to investigate the characteristics of surface water and groundwater, to assess the impact of artificial recharge as reinforcement of the natural replenishment and assess the renewal of groundwater under semi-arid area. Two major (...)

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Detrital monazite in the Tim Mersoï basin, Niger: provenance and contribution to the uranium budget in siliciclastic sediments

22 mars 2012

A detailed study using back-scattered electron imaging and electron-microprobe analysis shows that grains of detrital monazite are present in the Carboniferous, Permian, Triassic and Jurassic sediments of the Tim Mersoï basin, Niger. Despite variations in the size and shape of monazite grains, (...)

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The K-Ar Cassignol-Gillot technique applied to western Martinique lavas: A record of Lesser Antilles arc activity from 2 Ma to Mount Pelée volcanism

19 mars 2012

We present 23 new ages from three volcanic complexes of the Lesser Antilles arc in Martinique Island (French West Indies). These ages obtained with the K-Ar Cassignol-Gillot technique are distributed within the whole Quaternary. They allowed us to reconstruct a detailed history of successive (...)

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The volcanic evolution of Martinique Island: Insights from K-Ar dating into the Lesser Antilles arc migration since the Oligocene

19 mars 2012

The Lesser Antilles island arc bifurcates into two lines in its northern part, with an old branch to the east and a recent active branch to the west. Martinique is located at the southern tip of the separation. The two arcs diverge northward, and at maximum divergence are separated by a 50 km (...)

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Conditions for detection of ground deformation induced by conduit flow and evolution

15 mars 2012

At mature andesitic volcanoes, magma can reach the surface through the same path for several eruptions thus forming a volcanic conduit. Because of degassing, cooling, and crystallization, magma viscosity increase in the upper part of the conduit may induce the formation of a viscous plug. We (...)

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A mechanism for brief glacial episodes in the Mesozoic greenhouse

28 février 2012

The Mesozoic, perhaps the longest period of warmth during the Phanerozoic Earth history, has been repeatedly affected by short-lived cold interludes lasting about one million years. While the origin of these cold snaps has been classically attributed to a temporary atmospheric CO(2) drawdown, (...)

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Confocal Raman microscope mapping as a tool to describe different mineral and organic phases at high spatial resolution within marine biogenic carbonates : case study on Nerita undata (Gastropoda, Neritopsina)

27 février 2012

Marine biogenic carbonates formed by invertebrates (e. g. corals and mollusks) represent complex composites of one or more mineral phases and organic molecules. This complexity ranges from the macroscopic structures observed with the naked eye down to sub micrometric structures only revealed by (...)

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Dating the Lascaux cave gour formation

27 février 2012

Lascaux Cave is renowned for its outstanding prehistoric paintings, strikingly well-preserved over about 18,000 yr. While stalagmites and stalactites are almost absent in the cave, there is an extensive calcite flowstone that covered a large part of the cave until its opening for tourists (...)

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Is the pearl layer a reversed shell ? A re-examination of the theory of pearl formation through physical characterization of pearl and shell developmental stages in Pinctada margaritiefera

10 février 2012

A series of physical characterization methods (UV fluorescence microscopy, X-ray microdiffraction, backscattered electron imaging and X-ray absorption spectroscopy) were applied to Polynesian pearls collected after different cultivation periods, varying from three weeks to eighteen months. (...)

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High resolution ground-based digital photography for quantitative slope dynamics analysis : application to an arctic glacier basin (AustreLoven glacier, Spitsbergen 79 °N)

10 février 2012

Snow input is a significant element in order to understand a glacier system behaviour. On the glacier area itself, quantifying information coming from remote and in situ sensing is easily performed thanks to the smooth and flat surface. Such quantitative processing is however more complex on (...)

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La photographie terrestre haute résolution pour quantifier les dynamiques nivales de versants : l'exemple d'un bassin glaciaire arctique (Loven Est - Spitsberg 79°N)

31 janvier 2012

Pour comprendre le fonctionnement d'un système glaciaire, l'entrée nivologique est un élément capital. Abordé sur la zone glaciaire, il est assez aisé de quantifier l'information issue de données en télédétection et mesures in situ afin d'obtenir la fraction de couverture neigeuse ou de glace vive, (...)

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Contrasting isotopic signatures between anthropogenic and geogenic Zn and evidence for post-depositional fractionation processes in smelter-impacted soils from Northern France

13 janvier 2012

Zinc isotopes have been studied along two smelter-impacted soil profiles sampled near one of the largest Pb and Zn processing plants in Europe located in northern France, about 50 km south of Lille. Mean delta(66)Zn values along these two soil profiles range from +0.22 +/- 0.17 parts per (...)

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The Renpenning syndrome spectrum: new clinical insights supported by 13 new PQBP1-mutated males.

27 décembre 2011

Since the first reports of polyglutamine-binding protein 1 (PQBP1) mutations in Renpenning syndrome and related disorders, the spectrum of PQBP1-linked clinical manifestations has been outlined from rare published case reports. The phenotypic description is often obtained from medical archives, (...)

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The Renpenning syndrome spectrum: new clinical insights supported by 13 new PQBP1-mutated males.

27 décembre 2011

Since the first reports of polyglutamine-binding protein 1 (PQBP1) mutations in Renpenning syndrome and related disorders, the spectrum of PQBP1-linked clinical manifestations has been outlined from rare published case reports. The phenotypic description is often obtained from medical archives, (...)

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Mars cryosphere: a potential reservoir for heavy noble gases?

23 décembre 2011

The two orders of magnitude drop between the measured atmospheric abundances of non radiogenic argon, krypton and xenon in Earth versus Mars is striking. Here, in order to account for this difference, we explore the hypothesis that clathrate deposits incorporated into the current Martian (...)

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Can Moroccan Atlas lithospheric thinning and volcanism be induced by Edge-Driven Convection?

2 décembre 2011

The Moroccan lithosphere is characterized by an anomalously thinned area, located beneath the Atlas domains, which forms a singular narrow NE-SW directed strip overlain by Cenozoic alkaline volcanism. The origin of this thinning and volcanism is still a matter of debate. The proposed models (...)

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Atomic order of aragonite crystals formed by mollusks

15 novembre 2011

Aragonite is the most common polymorph of calcium carbonate produced by mollusks. The crystals have different shapes and sizes, and are intimately associated with an organic matrix. Here we adapt an infrared spectroscopic method that was developed to characterize atomic disorder in calcite (...)

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Atomic order of aragonite crystals formed by mollusks

15 novembre 2011

Aragonite is the most common polymorph of calcium carbonate produced by mollusks. The crystals have different shapes and sizes, and are intimately associated with an organic matrix. Here we adapt an infrared spectroscopic method that was developed to characterize atomic disorder in calcite (...)

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Further constraints on the diagenetic influences and salinity effect on Globigerinoides ruber (white) Mg/Ca thermometry : implications in the Mediterranean Sea

14 novembre 2011

We analyzed Mg/Ca ratios of the planktonic species Globigerinoides ruber (white) picked from 49 box core samples covering the whole Mediterranean Sea and 2 core tops from the Atlantic Ocean. Over the entire data set, we found no significant correlation between Mg/Ca and delta(18)O-derived (...)

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Further constraints on the diagenetic influences and salinity effect on Globigerinoides ruber (white) Mg/Ca thermometry : implications in the Mediterranean Sea

14 novembre 2011

We analyzed Mg/Ca ratios of the planktonic species Globigerinoides ruber (white) picked from 49 box core samples covering the whole Mediterranean Sea and 2 core tops from the Atlantic Ocean. Over the entire data set, we found no significant correlation between Mg/Ca and delta(18)O-derived (...)

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Irradiation creep of SA 304L and CW 316 stainless steels: Mechanical behaviour and microstructural aspects. Part II: Numerical simulation and test of SIPA model

10 novembre 2011

A cluster dynamic model has been adapted to test the Stress Induced Preferential Absorption of Defect (SIPA) on Frank loops hypothesis concerning irradiation creep, to reproduce quantitatively both microstructure evolution and its stress induced anisotropy and macroscopic creep rate. It is (...)

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Irradiation creep of SA 304L and CW 316 stainless steels: Mechanical behaviour and microstructural aspects. Part II: Numerical simulation and test of SIPA model

10 novembre 2011

A cluster dynamic model has been adapted to test the Stress Induced Preferential Absorption of Defect (SIPA) on Frank loops hypothesis concerning irradiation creep, to reproduce quantitatively both microstructure evolution and its stress induced anisotropy and macroscopic creep rate. It is (...)

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Isotopic and hydrochemical approach to the functioning of an aquifer system in the region of Marrakech (Morocco)

2 novembre 2011

A geochemical and isotopic (water and dissolved sulphate) study was performed on groundwater in the region of Marrakech, Morocco, with the aim of better understanding the regional hydrogeological system in order to improve water resources management. Significant differences in stable isotope (...)

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Isotopic and hydrochemical approach to the functioning of an aquifer system in the region of Marrakech (Morocco)

2 novembre 2011

A geochemical and isotopic (water and dissolved sulphate) study was performed on groundwater in the region of Marrakech, Morocco, with the aim of better understanding the regional hydrogeological system in order to improve water resources management. Significant differences in stable isotope (...)

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An enamel-like tissue, osteodermine, on the osteoderms of a fossil anguid (Glyptosaurinae) lizard

13 octobre 2011

The Glyptosaurinae, a fossil clade of anguid lizards, have robust osteoderms, with a granular ornamentation consisting of tubercles. In this study, the structural and histological features of these osteoderms are described in order to reconstruct their developmental pattern and further document (...)

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An enamel-like tissue, osteodermine, on the osteoderms of a fossil anguid (Glyptosaurinae) lizard

13 octobre 2011

The Glyptosaurinae, a fossil clade of anguid lizards, have robust osteoderms, with a granular ornamentation consisting of tubercles. In this study, the structural and histological features of these osteoderms are described in order to reconstruct their developmental pattern and further document (...)

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The 2010 European Venus Explorer (EVE) mission proposal

30 septembre 2011

The European Venus Explorer (EVE) mission described in this paper was proposed in December 2010 to ESA as an 'M-class' mission under the Cosmic Vision programme. It consists of a single balloon platform floating in the middle of the main convective cloud layer of Venus at an altitude of 55 km, (...)

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The 2010 European Venus Explorer (EVE) mission proposal

30 septembre 2011

The European Venus Explorer (EVE) mission described in this paper was proposed in December 2010 to ESA as an 'M-class' mission under the Cosmic Vision programme. It consists of a single balloon platform floating in the middle of the main convective cloud layer of Venus at an altitude of 55 km, (...)

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Segregation of olivine grains in volcanic sands in Iceland and implications for Mars

30 septembre 2011

Basaltic sands cover several plains in volcanic regions on Earth and dominate the aeolian sediments on Mars but basaltic sands are not as well characterized as felsic sands. The Lambahraun sandy-lava plain in Iceland was chosen as a martian analog to study the physical sorting of basaltic (...)

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The climate influence on the mid-depth Northeast Atlantic gyres viewed by cold-water corals

28 septembre 2011

The neodymium (Nd) isotopic composition (expressed in epsilon units, ɛNd) of reef framework-forming cold-water corals provides unique measures of water mass provenance and mixing within the Northeast Atlantic today and in the past. A reconstruction of near thermocline water ɛNd from cold-water (...)

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The volcanic evolution of Martinique Island : insights from K-Ar dating into the Lesser Antilles arc migration since the Oligocene

27 septembre 2011

The Lesser Antilles island arc bifurcates into two lines in its northern part, with an old branch to the east and a recent active branch to the west. Martinique is located at the southern tip of the separation. The two arcs diverge northward, and at maximum divergence are separated by a 50 km (...)

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A mechanism for brief glacial episodes in the Mesozoic greenhouse.

9 septembre 2011

The Mesozoic, perhaps the longest period of warmth during the Phanerozoic Earth history, has been repeatedly affected by short‐lived cold interludes lasting about one million years. While the origin of these cold snaps has been classically attributed to a temporary atmospheric CO2 drawdown, (...)

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A mechanism for brief glacial episodes in the Mesozoic greenhouse.

9 septembre 2011

The Mesozoic, perhaps the longest period of warmth during the Phanerozoic Earth history, has been repeatedly affected by short‐lived cold interludes lasting about one million years. While the origin of these cold snaps has been classically attributed to a temporary atmospheric CO2 drawdown, (...)

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Volcanic sands of Iceland - Diverse origins of aeolian sand deposits revealed at Dyngjusandur and Lambahraun

6 septembre 2011

The origin, formation and evolution of volcanic sands are less well known than the formation of the much more common quartz-rich sand sheets. Combining active volcanism and a cold climate, Iceland is covered for about 21% of its surface by sandy areas. The sands were analyzed in detail at two (...)

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Volcanic sands of Iceland - Diverse origins of aeolian sand deposits revealed at Dyngjusandur and Lambahraun

6 septembre 2011

The origin, formation and evolution of volcanic sands are less well known than the formation of the much more common quartz-rich sand sheets. Combining active volcanism and a cold climate, Iceland is covered for about 21% of its surface by sandy areas. The sands were analyzed in detail at two (...)

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A two-step process for the reflooding of the Mediterranean after the Messinian Salinity Crisis

25 août 2011

The Messinian Salinity Crisis is well known to have resulted from a significant drop of the Mediterranean sea level. Considering both onshore and offshore observations, the subsequent reflooding is generally thought to have been very sudden. We present here offshore seismic evidence from the (...)

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A two-step process for the reflooding of the Mediterranean after the Messinian Salinity Crisis

25 août 2011

The Messinian Salinity Crisis is well known to have resulted from a significant drop of the Mediterranean sea level. Considering both onshore and offshore observations, the subsequent reflooding is generally thought to have been very sudden. We present here offshore seismic evidence from the (...)

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The evolution of Venus : present state of knowledge and future exploration

21 juillet 2011

A detailed characterization of the formation and evolution of Venus is a key link to the study of terrestrial planets, and to their divergent evolutions. While Earth and to a lesser extent Mars (thanks to the analysis of SNC meteorites) are extensively studied in a comparative planetology (...)

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The evolution of Venus : present state of knowledge and future exploration

21 juillet 2011

A detailed characterization of the formation and evolution of Venus is a key link to the study of terrestrial planets, and to their divergent evolutions. While Earth and to a lesser extent Mars (thanks to the analysis of SNC meteorites) are extensively studied in a comparative planetology (...)

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Crustal and lithospheric structure of the Alborz Mountains (Iran) and surrounding areas from integrated geophysical modeling

21 juillet 2011

Using gravity, geoid, topography and surface heat flow data, we have modeled the density and temperature distribution in the lithosphere along three profiles crossing Iran in SW-NE direction from the Arabian foreland in the SW to the South Caspian Basin and the Turan Platform to the NE. We find (...)

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Crustal and lithospheric structure of the Alborz Mountains (Iran) and surrounding areas from integrated geophysical modeling

21 juillet 2011

Using gravity, geoid, topography and surface heat flow data, we have modeled the density and temperature distribution in the lithosphere along three profiles crossing Iran in SW-NE direction from the Arabian foreland in the SW to the South Caspian Basin and the Turan Platform to the NE. We find (...)

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Experimental study of ERT monitoring ability to measure solute dispersion

13 juillet 2011

This paper reports experimental measurements performed to test the ability of electrical resistivity tomography (ERT) imaging to provide quantitative information about transport parameters in porous media such as the dispersivity α, the mixing front velocity u, and the retardation factor Rf (...)

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Experimental study of ERT monitoring ability to measure solute dispersion

13 juillet 2011

This paper reports experimental measurements performed to test the ability of electrical resistivity tomography (ERT) imaging to provide quantitative information about transport parameters in porous media such as the dispersivity α, the mixing front velocity u, and the retardation factor Rf (...)

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Isotopes and groundwater management strategies under semi-arid area : case of the Souss upstream basin (Morocco)

12 juillet 2011

This study concerns the Souss upstream basin. The objective is to investigate the characteristics of surface water and groundwater, to assess the impact of artificial recharge as reinforcement of the natural replenishment and assess the renewal of groundwater under semi-arid area. Two major (...)

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Isotopes and groundwater management strategies under semi-arid area : case of the Souss upstream basin (Morocco)

12 juillet 2011

This study concerns the Souss upstream basin. The objective is to investigate the characteristics of surface water and groundwater, to assess the impact of artificial recharge as reinforcement of the natural replenishment and assess the renewal of groundwater under semi-arid area. Two major (...)

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Detrital monazite in the Tim Mersol Basin, Niger : provenance and contribution to the uranium budget in siliciclastic sediments

12 juillet 2011

A detailed study using back-scattered electron imaging and electron-microprobe analysis shows that grains of detrital monazite are present in the Carboniferous, Permian, Triassic and Jurassic sediments of the Tim Mersoi basin, Niger. Despite variations in the size and shape of monazite grains, (...)

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Detrital monazite in the Tim Mersol Basin, Niger : provenance and contribution to the uranium budget in siliciclastic sediments

12 juillet 2011

A detailed study using back-scattered electron imaging and electron-microprobe analysis shows that grains of detrital monazite are present in the Carboniferous, Permian, Triassic and Jurassic sediments of the Tim Mersoi basin, Niger. Despite variations in the size and shape of monazite grains, (...)

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Conditions for detection of ground deformation induced by conduit flow and evolution

11 juillet 2011

At mature andesitic volcanoes, magma can reach the surface through the same path for several eruptions thus forming a volcanic conduit. Because of degassing, cooling, and crystallization, magma viscosity increase in the upper part of the conduit may induce the formation of a viscous plug. We (...)

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Conditions for detection of ground deformation induced by conduit flow and evolution

11 juillet 2011

At mature andesitic volcanoes, magma can reach the surface through the same path for several eruptions thus forming a volcanic conduit. Because of degassing, cooling, and crystallization, magma viscosity increase in the upper part of the conduit may induce the formation of a viscous plug. We (...)

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Effects of ice content on the thermal erosion of permafrost : implications for coastal and fluvial erosion

16 juin 2011

The effects of ice content and water flow on thawing and erosion of non-cohesive permafrost banks were investigated through laboratory experiments. A critical ice content was identified as associated with turbulent flows (20% and 80% for Reynolds numbers of 15 900 and 12 700, respectively), (...)

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Effects of ice content on the thermal erosion of permafrost : implications for coastal and fluvial erosion

16 juin 2011

The effects of ice content and water flow on thawing and erosion of non-cohesive permafrost banks were investigated through laboratory experiments. A critical ice content was identified as associated with turbulent flows (20% and 80% for Reynolds numbers of 15 900 and 12 700, respectively), (...)

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Shell layers of the black-lip pearl oyster Pinctada margaritifera : matching microstructure and composition

10 juin 2011

The nacre prism transition of the mollusc shell Pinctada margaritifera was studied using scanning electron microscopy, electron probe micro-analysis (EPMA) and time-of-flight secondary ion mass spectrometry (TOF-SIMS). Mineralogical change is correlated with a change in organic matrix. Previous (...)

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Shell layers of the black-lip pearl oyster Pinctada margaritifera : matching microstructure and composition

10 juin 2011

The nacre prism transition of the mollusc shell Pinctada margaritifera was studied using scanning electron microscopy, electron probe micro-analysis (EPMA) and time-of-flight secondary ion mass spectrometry (TOF-SIMS). Mineralogical change is correlated with a change in organic matrix. Previous (...)

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Boron isotopes as pH proxy : a new look at boron speciation in deep-sea corals using B-11 MAS NMR and EELs

24 mai 2011

Dissolved boron in modern seawater occurs in the form of two species, trigonal boric acid B(OH)(3) and tetrahedral borate ion B(OH)(4)(-). One of the key assumption in the use of boron isotopic compositions of carbonates as pH proxy is that only borate ions, B(OH)(4)(-), are incorporated into (...)

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Boron isotopes as pH proxy : a new look at boron speciation in deep-sea corals using B-11 MAS NMR and EELs

24 mai 2011

Dissolved boron in modern seawater occurs in the form of two species, trigonal boric acid B(OH)(3) and tetrahedral borate ion B(OH)(4)(-). One of the key assumption in the use of boron isotopic compositions of carbonates as pH proxy is that only borate ions, B(OH)(4)(-), are incorporated into (...)

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In-pore tensile stress by drying-induced capillary bridges inside porous materials

24 mai 2011

We present here some evidences that capillary liquid bridges are able to deform micrometric cylindrical pores by tensile stress. Brine-soaked filter membranes are submitted to drying conditions leading to NaCl precipitation inside the 5-10 mu m pores. A close examination demonstrated that two (...)

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Salt precipitation and trapped liquid cavitation in micrometric capillary tubes.

2 mai 2011

Laboratory evidence shows that the occurrence of solid salt in soil pores causes drastic changes in the topology of the porous spaces and possibly also in the properties of the occluded liquid. Observations were made on NaCl precipitation in micrometric cylindrical capillary tubes, filled with (...)

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Salt precipitation and trapped liquid cavitation in micrometric capillary tubes.

2 mai 2011

Laboratory evidence shows that the occurrence of solid salt in soil pores causes drastic changes in the topology of the porous spaces and possibly also in the properties of the occluded liquid. Observations were made on NaCl precipitation in micrometric cylindrical capillary tubes, filled with (...)

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The evolution of Venus: present state of knowledge and future exploration

30 avril 2011

A detailed characterization of the formation and evolution of Venus is a key link of the study of terrestrial planets, and of their divergent evolutions. Whereas Earth and to a lesser extent Mars (thanks to the analysis of SNC meteorites) are extensively studied in a comparative planetology (...)

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Calcein staining of calcified structures in pearl oyster Pinctada margaritifera and the effect of food resource level on shell growth

19 avril 2011

Marine mollusc shell growth has been widely measured using fluorochrome marking. In order to test the efficiency and reliability of calcein staining on Pinctada margaritifera shells and pearls, the present study examined two administration methods, different concentrations and several immersion (...)

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Calcein staining of calcified structures in pearl oyster Pinctada margaritifera and the effect of food resource level on shell growth

19 avril 2011

Marine mollusc shell growth has been widely measured using fluorochrome marking. In order to test the efficiency and reliability of calcein staining on Pinctada margaritifera shells and pearls, the present study examined two administration methods, different concentrations and several immersion (...)

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An attempt to constraint the age, duration and eruptive history of the Karoo Flood Basalt : the Naude's Nek Section (South Africa).

13 avril 2011

We have carried out paleomagnetic sampling of a similar to 750 m sequence of the Karoo large igneous province (Naude's Nek Pass, South Africa). K-Ar dating (Cassignol-Gillot) has been performed on four samples from the 650 m upper unit (mean age 179.2 +/- 1.8 Ma) and a sample from the lower (...)

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An attempt to constraint the age, duration and eruptive history of the Karoo Flood Basalt : the Naude's Nek Section (South Africa).

13 avril 2011

We have carried out paleomagnetic sampling of a similar to 750 m sequence of the Karoo large igneous province (Naude's Nek Pass, South Africa). K-Ar dating (Cassignol-Gillot) has been performed on four samples from the 650 m upper unit (mean age 179.2 +/- 1.8 Ma) and a sample from the lower (...)

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Trenchward Plio-Quaternary volcanism in the Trans-Mexican Volcanic Belt : the case of the Sierra Nevada Range

6 avril 2011

The Miocene-Quaternary Trans-Mexican Volcanic arc is thought to have grown southwards (i.e. trenchward) since the Pliocene. This theory is mainly supported by roughly N-S-directed polygenetic volcanic ranges along which volcanic activity migrates southwards with time. We investigated the (...)

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Trenchward Plio-Quaternary volcanism in the Trans-Mexican Volcanic Belt : the case of the Sierra Nevada Range

6 avril 2011

The Miocene-Quaternary Trans-Mexican Volcanic arc is thought to have grown southwards (i.e. trenchward) since the Pliocene. This theory is mainly supported by roughly N-S-directed polygenetic volcanic ranges along which volcanic activity migrates southwards with time. We investigated the (...)

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NMR relaxation of neritic carbonates : an integrated petrophysical and petrographical approach

18 mars 2011

A set of carbonate outcrop samples, covering a wide range of the sedimentary textures and depositional environments existing on carbonate systems, was studied through an integrated petrographical and petrophysical approach. With the aim of improving the understanding of the NMR (Nuclear (...)

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NMR relaxation of neritic carbonates : an integrated petrophysical and petrographical approach

18 mars 2011

A set of carbonate outcrop samples, covering a wide range of the sedimentary textures and depositional environments existing on carbonate systems, was studied through an integrated petrographical and petrophysical approach. With the aim of improving the understanding of the NMR (Nuclear (...)

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Chemical weathering in Malay Peninsula and North Borneo : clay mineralogy and element geochemistry of river surface sediments

18 mars 2011

Weathering products of silicate rocks are particularly useful for evaluating the continental chemical weathering on the Earth's surface and its mechanism. Clay mineralogy and major-element geochemistry of surface sediment samples collected in major rivers of Malay Peninsula and North Borneo in (...)

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Chemical weathering in Malay Peninsula and North Borneo : clay mineralogy and element geochemistry of river surface sediments

18 mars 2011

Weathering products of silicate rocks are particularly useful for evaluating the continental chemical weathering on the Earth's surface and its mechanism. Clay mineralogy and major-element geochemistry of surface sediment samples collected in major rivers of Malay Peninsula and North Borneo in (...)

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High resolution electron backscatter diffraction (EBSD) data from calcite biominerals in recent gastropod shells

15 mars 2011

Electron backscatter diffraction (EBSD) is a microscopy technique that reveals in situ crystallographic information. Currently, it is widely used for the characterization of geological materials and in studies of biomineralization. Here, we analyze high resolution EBSD data from biogenic (...)

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High resolution electron backscatter diffraction (EBSD) data from calcite biominerals in recent gastropod shells

15 mars 2011

Electron backscatter diffraction (EBSD) is a microscopy technique that reveals in situ crystallographic information. Currently, it is widely used for the characterization of geological materials and in studies of biomineralization. Here, we analyze high resolution EBSD data from biogenic (...)

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The K-Ar Cassignol-Gillot technique applied to western Martinique lavas : a record of the Lesser Antilles arc activity from 2 Ma to Mount Pelée volcanism

15 mars 2011

We present 23 new ages from three volcanic complexes of the Lesser Antilles arc in Martinique Island (French West Indies). These ages obtained with the K-Ar Cassignol-Gillot technique are distributed within the whole Quaternary. They allowed us to reconstruct a detailed history of successive (...)

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New U-Pb (ID-TIMS and LA-ICPMS) and 40Ar/39Ar geochronological constraints of the Cretaceous geologic time scale calibration from Hokkaido (Japan).

15 mars 2011

We present new radiometric ages in order to constrain the calibration of the Cretaceous time scale. They have been obtained from volcanic tuffs sampled at Hokkaido (Japan) within the Northwest Pacific marine succession of the Yezo Group, and are compared with ages from the Western Interior and (...)

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Conditions for detection of ground deformation induced by conduit flow and evolution

15 mars 2011

At mature andesitic volcanoes, magma can reach the surface through the same path for several eruptions thus forming a volcanic conduit. Because of degassing, cooling, and crystallization, magma viscosity increase in the upper part of the conduit may induce the formation of a viscous plug. We (...)

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Climate and sea-level variations along the northwestern Tethyan margin during the Valanginian C-isotope excursion : mineralogical evidence from the Vocontian Basin (SE France)

1er mars 2011

A high resolution mineralogical study (bulk-rock and clay-fraction) was carried out upon the hemipelagic strata of the Angles section (Vocontian Basin, SE France) in which the Valanginian positive C-isotope excursion occurs. To investigate sea-level fluctuations and climate change respectively, (...)

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Scalloped depressions and small-sized polygons in western Utopia Planitia, Mars : a new formation hypothesis

1er mars 2011

Flat-floored depressions with scalloped-shapes and spatially associated small-sized polygons (diameter < similar to 100 m) dot the landscape of western Utopia Planitia (centered at 45 degrees N-95 degrees E). The scalloped depressions are thought to be the result of ice-rich regolith (...)

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Large asymmetric polar scarps on Planum Australe, Mars : characterization and evolution

1er mars 2011

Numerous scarps with similar characteristics have been observed in the polar layered deposits of Planum Australe, Mars. They are referred to as LAPSs (for Large Asymmetric Polar Scarps) because of their typical cross-section featuring a trough between a straight slope on one side with outcrops (...)

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From Central Atlantic continental rift to Neogene uplift - western Anti-Atlas (Morocco).

18 février 2011

P>To put constraints on the Mesozoic to recent growth of the Anti-Atlas system, we investigated the temperature-time history of rocks by applying extensive low-temperature thermochronological analysis to three Precambrian inliers along the coast and 250 km into the interior. Bedrocks yield (...)

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Climatic ups and downs in a disturbed Jurassic world.

14 février 2011

The tropical, warm, and equable climate of the Jurassic world is regularly challenged by geoscientists, especially since oxygen isotopes ( 18O) of fossil hardparts have been used to reconstruct the paleotemperature history of seawater. By applying the innovative “SiZer” (significant zero (...)

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In-Pore stress by drying-induced capillary bridges inside porous materials.

4 janvier 2011

We present here some evidences that capillary liquid bridges are able to deform micrometric cylindrical pores by tensile stress. Brine-soaked filter membranes are submitted to drying conditions leading to NaCl precipitation inside the 5-10 μm pores. A close examination demonstrated that two (...)

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Northeastern Atlantic cold-water coral reefs and climate

3 janvier 2011

U-series age patterns obtained on reef framework-forming cold-water corals collected over a nearly 6000-km-long continental margin sector, extending from off Mauritania (17 degrees N; northwest Africa) to the southwestern Barents Sea (70 degrees N; northeastern Europe), reveal strong climate (...)

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Water ice in the dark dune spots of Richardson crater on Mars

14 décembre 2010

Interfacial liquid water has been hypothesized to form during the seasonal evolution of the dark dune spots observed in the high latitudes of Mars. In this study we assess the presence, nature and properties of ices - in particular water ice - that occur within these spots using HIRISE and (...)

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Stratigraphy, mineralogy and origin of layered deposits inside Terby crater, Mars

13 décembre 2010

The 174 km diameter Terby impact crater (28.0 degrees S-74.1 degrees E) located on the northern rim of the Hellas basin displays anomalous inner morphology, including a flat floor and light-toned layered deposits. An analysis of these deposits was performed using multiple datasets from Mars (...)

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Explaining the redox imbalance between the H and O escape fluxes at Mars by the oxidation of methane

18 octobre 2010

From a comparison between the different observations of Martian methane existing today, including the new TES methane maps (Fonti and Marzo, 2010), we show that all sets of data are globally consistent with each other, and that a well definite seasonal cycle of methane has been at work for at (...)

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Methane release and the carbon cycle on Mars

17 septembre 2010

It has been suggested that the present release rate of methane to the Martian atmosphere could be the result of serpentinization in the deep subsurface, followed by the conversion of H2 to CH4 in a CO2-rich fluid. Making this assumption, we show that the cryosphere could act as a buffer storing (...)

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The importance of the terrigenous fraction within a cold-water coral mound : A case study

24 août 2010

In the nineties, cold-water coral mounds were discovered in the Porcupine Seabight (NE Atlantic. west of Ireland). A decade later, this discovery led to the drilling of the entire Challenger cold-water coral mound (Eastern slope, Porcupine Seabight) during IODP Expedition 307. As more than 50% (...)

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