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New aspects of magma storage and transfer CR Geosci. (IF 1.4) Pub Date : 2019-12-01 Bruno Scaillet,Laurent Arbaret,Fabrice Gaillard
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The intermediate step in fractionation trends of mildly alkaline volcanic suites: An experimental insight from the Pavin trachyandesite (Massif Central, France) CR Geosci. (IF 1.4) Pub Date : 2019-12-01 Morgane Rondet, Caroline Martel, Jean-Louis Bourdier
Abstract We examined magma storage conditions and eruptive dynamics for the trachyandesite (~58 wt% SiO2, 9–10 wt% alkalis) of the Pavin monogenetic volcano, a maar-like explosive crater belonging to a small group of youngest volcanoes in the Massif Central. By confronting the natural samples to experimental products, we constrained pre-eruptive conditions around 950–975 °C, 150–200 MPa (~5.5–7.0 km
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Effect of anorthite on granite phase relations: Experimental data and models CR Geosci. (IF 1.4) Pub Date : 2019-12-01 Michel Pichavant, Catherine Weber, Arnaud Villaros
New experimental data on the effect of anorthite (An) on liquidus phase equilibria in the system Qz–Ab–Or are presented. The data were obtained for 5 wt% An added to variable Qz/Ab/Or compositions at 300 MPa and under H2O-saturated conditions. Crystal–liquid equilibria were determined for 13 synthetic glass compositions made from gels in experiments performed between 660 and 750 °C in cold-seal pressure
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Titanite: A potential solidus barometer for granitic magma systems CR Geosci. (IF 1.4) Pub Date : 2019-12-01 Saskia Erdmann, Rucheng Wang, Fangfang Huang, Bruno Scaillet, Kai Zhao, Hongsheng Liu, Yan Chen, Michel Faure
Constraining crystallization pressure and thus intrusion depth of granites in various geodynamic settings remains challenging, yet important to further our understanding of magma system and crustal evolution. We propose that titanite, which is a common accessory in metaluminous and weakly peraluminous granites, can be used as a barometer if it crystallized in magmatic, near-solidus conditions and in
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Secular cooling and crystallization of partially molten Archaean continental crust over 1 Ga CR Geosci. (IF 1.4) Pub Date : 2019-12-01 Olivier Vanderhaeghe, Célia Guergouz, Cécile Fabre, Stéphanie Duchêne, David Baratoux
Abstract The protracted tectonic and magmatic record of cratons over the Archaean Eon has been classically interpreted in terms of long-lived shallow-dipping subduction or repeated mantle plumes. In this paper, we use the 1D conductive heat equation to model the evolution of the geotherm of a generic felsic-dominated Archaean cratonic nuclei solely considering the secular decay of radioactive isotopes
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Crystal clustering in magmas: Insights from HP–HT experiments CR Geosci. (IF 1.4) Pub Date : 2019-12-01 Laurent Arbaret, Misha Bystricky, Patrick Launeau
We have studied by high-resolution X-ray Computed Tomography the effect of crystal clustering on the Shape-Preferred Orientation (SPO) development in synthetic magmas experimentally deformed at 300 MPa and 475–550°C. A fully connected solid network that could potentially induce the onset of yield strength is not achieved in these suspensions containing 16 vol% of crystals. The alumina grain population
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Developments in the stratigraphy of the Deccan Volcanic Province, peninsular India CR Geosci. (IF 1.4) Pub Date : 2019-10-01 Omkar Verma, Ashu Khosla
Abstract The Deccan Volcanic Province has been considered as one of the largest magmatic regions, involving an aerial coverage of ca. 500,000 km2. It is subdivided into four sub-provinces, and holds a unique position in global tectonic models for understanding earth's geodynamics and the impact of voluminous eruptions on the contemporary biosystem and climate system. Published stratigraphic data suggest
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The Cretaceous marine onlap on Palaeozoic deposits (Smara–Lâayoune Basin, South Morocco). Comparison with neighbouring regions CR Geosci. (IF 1.4) Pub Date : 2019-10-01 Mohamed Abioui, Serge Ferry, Danièle Grosheny, Nourrissaid Içame, Emmanuel Robert, Mohammed Benssaou
Abstract The Cretaceous marine transgression proceeded through successive steps from the Albian to the Turonian (dated with ammonites). The onlapping wedge begins with coastal transgressive–regressive short-term sequences on massive, probably fluvial sandstones to be correlated with the very thick continental Lower Cretaceous succession found in the Puerto Cansado well in the Tarfaya sub-basin to the
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Comparison of hydrological models for use in climate change studies: A test on 241 catchments in West and Central Africa CR Geosci. (IF 1.4) Pub Date : 2019-10-01 Kiswendsida Samiratou Ouermi, Jean-Emmanuel Paturel, Julien Adounpke, Agnidé Emmanuel Lawin, Bi Tié Albert Goula, Ernest Amoussou
Abstract The present work reports on the study and the comparison of the performance of three “Genie rural” (GR) and two Water Balance (WB) models. The calibration and robustness performances are analysed in the light of the hydro-climatic conditions. The study shows that the GR models are much more efficient and robust than the WB models. The behaviour of calibration performance as a function of hydroclimatic
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Use of the magnetic, geochemical, and sedimentary records in establishing paleoclimate change in the environment of Sebkha: Case of the Sebkha Mhabeul in southeastern Tunisia CR Geosci. (IF 1.4) Pub Date : 2019-10-01 Mariem Ben Ameur, Sameh Masmoudi, Abdelhakim Abichou, Mounir Medhioub, Chokri Yaich
Abstract In this study, we explored the evidence of late Holocene climate changes in southern Tunisia, examining extreme events of flood and sandstorm sedimentary succession records, in Sebkha Mhabeul. A sediment-derived climatic proxy was inferred from a 93.5-cm-deep core (Mh1), whose dating by tephrochronology has already been achieved in previous works. Multiple geochemical, sedimentological, magnetic
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A new 3D laser-scanning and GPS combined measurement system CR Geosci. (IF 1.4) Pub Date : 2019-10-01 Liang Li, Xingyan Cao, Qiang He, Jie Sun, Bingsong Jia, Xiang Dong
Abstract Terrestrial laser scanning (TLS) is widely used because of its ability to quickly acquire high-density and high-precision 3D image and topographic data. However, it can only acquire independent coordinate system points, which restricts its application in large-scale deformation monitoring. In this study, we constructed a measurement system to acquire global coordinate point cloud data by combining
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Geophysical methods for mapping quaternary sediment thickness: Application to the Saint-Lary basin (French Pyrenees) CR Geosci. (IF 1.4) Pub Date : 2019-08-01 Pierre Bottelin, Grégory Dufréchou, Lucia Seoane, Muriel Llubes, Bernard Monod
This study aims at mapping the sediment infill thickness in the Saint-Lary basin (Aure valley, French Pyrenees). For this purpose, we combine passive seismic and gravity surveys. The resonance frequencies of the sediment body are retrieved from seismic ambient measurements, while the gravimetric survey shows negative residual anomaly of about -3 mGal in the basin. Both methods reveal unexpected but
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Groundwater recharge study based on hydrological data and hydrological modelling in a South American volcanic aquifer CR Geosci. (IF 1.4) Pub Date : 2019-08-01 Maurício D. Melati, Fernando M. Fan, Gustavo B. Athayde
Abstract In humid subtropical regions, baseflow is mainly governed by aquifer discharges and this dynamic is fed by groundwater recharge. To better comprehend the watershed groundwater recharge using a large-scale approach, two watersheds located over the Serra Geral Aquifer System (Southern South America) were studied. Three different groundwater recharge methods were utilized to study the baseflow:
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Phosphatic series under Plio-Quaternary cover of Tadla Plain, Morocco: Gravity and seismic data CR Geosci. (IF 1.4) Pub Date : 2019-08-01 Nadia El Kiram, Mohammed Jaffal, Azzouz Kchikach, Driss El Azzab, Mustapha El Ghorfi, Oussama Khadiri, Es-Said Jourani, Ahmed Manar, Mohamed Nahim
Abstract The Ouled Abdoun sedimentary basin in Morocco contains the largest phosphate reserves in the world. To the Northwest of the basin, the phosphate layers crop out or are at a shallow depth and are exploited in open pit mines. By contrast, towards the central and southwestern parts of the basin, the phosphate layers lay below the Plio-Quaternary sediments of the Tadla Plain. This study aims to
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Crustal structure beneath the Mount Cameroon region derived from recent gravity measurements CR Geosci. (IF 1.4) Pub Date : 2019-08-01 Severin Nguiya, Marcelin Mouzong Pemi, Alain Pierre Tokam, Évariste Ngatchou Heutchi, Willy Lemotio
Abstract In this study, the recent update of the gravity database with new measurements has raised the opportunity of improving the knowledge of the crustal structure beneath the large volcanic system called Mount Cameroon, and its implication in the regional tectonics. The multi-scale wavelet analysis method was applied to highlight the geologic features of the area, and their depths were estimated
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Holocene palaeogeographical reconstruction and relative sea-level changes in the southeastern part of the island of Samos (Greece) CR Geosci. (IF 1.4) Pub Date : 2019-08-01 Niki Evelpidou, Kosmas Pavlopoulos, Konstantinos Vouvalidis, George Syrides, Maria Triantaphyllou, Anna Karkani, Theodoros Paraschou
Abstract In this paper, we focus on the southeastern coastal zone of the island of Samos (east-central Aegean Sea), in order to reconstruct the evolution of coastal landscapes and the relative sea-level changes during the late Holocene. We use geomorphological mapping, sedimentological and palaeontological proxies of late Holocene coastal deposits from two lagoon environments. We further compare our
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Variscan stress regime rotation: Insights from the analysis of kink folds in the northern margin of the Bohemian Massif, South Poland CR Geosci. (IF 1.4) Pub Date : 2019-06-01 Jerzy Żaba, Krzysztof Gaidzik
Abstract We aimed to determine variations in stress regimes during the youngest Variscan deformations in the northern part of the Bohemian Massif. For this purpose, we calculated the orientation of the principal stress and strain axes for kink folds observed in the metamorphic envelope of the Karkonosze Granite, using two methods: 1) the traditional method, incorporating structural diagrams (for conjugate
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Tectono-metamorphic evolution of the European continental margin involved in the Alpine subduction: New insights from Alpine Corsica, France CR Geosci. (IF 1.4) Pub Date : 2019-06-01 Maria Di Rosa, Chiara Frassi, Francesca Meneghini, Michele Marroni, Luca Pandolfi, Alberto De Giorgi
Abstract In Corsica, continental units (the Lower Units) affected by high-pressure metamorphism represent the remains of the European margin deformed during the Alpine orogeny. In order to document how Alpine deformation and metamorphism changed along the European margin involved in the Alpine subduction, we selected three key areas: the Corte, Cima Pedani, and Ghisoni transects. The three transects
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Structural evolution of the Téfidet trough (East Aïr, Niger) in relation with the West African Cretaceous and Paleogene rifting and compression episodes CR Geosci. (IF 1.4) Pub Date : 2019-06-01 Moussa Konaté, Yacouba Ahmed, Moussa Harouna
Abstract Located in northern Niger, the NW–SE Tefidet trough is the western branch of the Tenere rift megasystem. Here we present a tectono-sedimentary analysis of the Tefidet trough, based on the combined use of satellite imagery, field observations and measures, and available literature. We use these data to analyse the sedimentary facies and the tectonic deformations (faults, folds, basins) in the
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Morphometric analysis of the drainage network of Samos Island (northern Aegean Sea): Insights into tectonic control and flood hazards CR Geosci. (IF 1.4) Pub Date : 2019-06-01 Nikos Charizopoulos, Panagiotis Mourtzios, Thomas Psilovikos, Aris Psilovikos, Lina Karamoutsou
Abstract The morphometric analysis of alluvial drainage provides insights into its dynamics, erosion capacity, susceptibility to floods and possible genetic relations to tectonic faulting. In this study, we analysed the drainage system of Samos Island, located in the northern Aegean Sea. The results indicate a vulnerability to erosion and flooding events, and these intense phenomena concentrate mostly
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Petrogenesis and tectonic significance of mafic-ultramafic rocks from southwestern Yunnan, China CR Geosci. (IF 1.4) Pub Date : 2019-06-01 Qing Shi, Nianqiao Fang
Abstract This study focuses on the mafic-ultramafic lavas of the Early Carboniferous outcrop in Mangxin, southwestern Yunnan, China. Picrites with 26–32 wt% MgO and a quenched texture are the most significant components of this rock association. This article divides the Mangxin picrites into two types. The mantle potential temperature (Tp) of these picrites is higher than the Tp range of mid-ocean
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Optimization approach to retrieve soil surface parameters from single-acquisition single-configuration SAR data CR Geosci. (IF 1.4) Pub Date : 2019-04-01 Arsalan Ghorbanian, Mahmod Reza Sahebi, Ali Mohammadzadeh
Abstract This study suggests a novel approach to the retrieval of soil surface parameters using a single-acquisition single-configuration synthetic-aperture radar (SAR) system. Soil surface parameters such as soil moisture and surface roughness are key elements for many environmental studies, including Earth surface water cycles, energy exchange, agriculture, and geology. Remote sensing techniques
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Mineralogical and seismic properties of serpentinite of Ait Ahmane fault zone of Bou Azzer ophiolite, central Anti-Atlas of Morocco CR Geosci. (IF 1.4) Pub Date : 2019-04-01 Mohamed Bhilisse, Hassan Admou, Ali Aydda, Lhou Maacha
Abstract This paper presents the first seismic measurements of serpentinite of Bou Azzer ophiolite, central Anti-Atlas of Morocco, including seismic velocities and anisotropy. Two serpentinite samples collected from the Ait Ahmane fault zone were analyzed in order to define the mineralogical and seismic features of the natural serpentinite of the Bou Azzer ophiolite. The mineralogical features were
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The ore genesis of the Jebel Mecella and Sidi Taya F Ba (Zn Pb) Mississippi Valley-type deposits, Fluorite Zaghouan Province, NE Tunisia, in relation to Alpine orogeny: Constraints from geological, sulfur, and lead isotope studies CR Geosci. (IF 1.4) Pub Date : 2019-04-01 Nejib Jemmali, Larbi Rddad, Fouad Souissi, Emmanuel John M. Carranza
Abstract Jebel Mecella and Sidi Taya F–(Ba Pb Zn) deposits are located within the Fluorite Zaghouan Province (NE Tunisia). The mineralization occurs along the unconformity surface between the Jurassic limestones and Upper Cretaceous rocks. The mineralization consists mainly of fluorite, barite, sphalerite, and galena. The δ34S values of barite at Jebel Mecella (14.8–15.4‰) and at Sidi Taya (21.6–22
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Progradation and retrogradation of the Medjerda delta during the 20th century (Tunisia, western Mediterranean) CR Geosci. (IF 1.4) Pub Date : 2019-04-01 Thouraya Ben Moussa, Oula Amrouni, Abderraouf Hzami, Laurent Dezileau, Gil Mahé, Saâdi Abdeljaouad
Abstract The aim of this study is the reconstitution of the recent morpho-sedimentary evolution of the Medjerda River delta. We examine the spatio-temporal evolution of the Medjerda shoreline between 1936 and 2016 using satellite images, complemented by sedimentological and geochemical analyses and 210Pbex and 137Cs radiometric data. The general tendency of the shoreline evolution shows an increasing
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Mapping of aboveground biomass in Gabon CR Geosci. (IF 1.4) Pub Date : 2019-04-01 Mohammad El Hajj, Nicolas Baghdadi, Nicolas Labrière, Jean-Stéphane Bailly, Ludovic Villard
The aim of this paper is to map the aboveground biomass (AGB) in Gabon. First, a random forest (RF) model that relates reference AGB values to remote sensing (RS)-derived variables (mainly radar and optical images) was built, and the significant predictive variables were determined. Second, the built RF model was applied to the significant RS-derived variables to predict AGB across Gabon. The results
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Sur la période des maxima d’activité solaire CR Geosci. (IF 1.4) Pub Date : 2019-04-01 Jean Malburet
Abstract 1 This is the publication of a pli cachete (sealed letter) submitted to the French Academy of Sciences in 1918 by Jean Malburet (amateur astronomer, 1879–1955). The subject is “On the period of solar activity maxima”. If not reclaimed for 100 years, such sealed letters are opened and analysed by members of the Academy. This letter was considered sufficiently interesting to be published in
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High-Pressure Mineral Physics Seminar, 9th Edition CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Guillaume Fiquet,James Badro
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Development of density measurement for metals at high pressures and high temperatures using X-ray absorption imaging combined with externally heated diamond anvil cell CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Yusaku Takubo, Hidenori Terasaki, Tadashi Kondo, Shingo Mitai, Seiji Kamada, Takumi Kikegawa, Akihiko Machida
Abstract A technique for density measurement under high pressure and high temperature was developed using the X-ray absorption imaging method combined with an externally heated diamond anvil cell. The densities of solid and liquid In were measured in the pressure and temperature ranges of 3.2–18.6 GPa and 294–719 K. The densities obtained through the X-ray absorption imaging method were in good agreement
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Elastic constants of single-crystal Pt measured up to 20 GPa based on inelastic X-ray scattering: Implication for the establishment of an equation of state CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Seiji Kamada, Hiroshi Fukui, Akira Yoneda, Hitoshi Gomi, Fumiya Maeda, Satoshi Tsutsui, Hiroshi Uchiyama, Naohisa Hirao, Daisuke Ishikawa, Alfred Q.R. Baron
Abstract Phonon velocities and densities for Pt were measured based on inelastic X-ray scattering from ambient pressure to 20 GPa in order to independently determine its equation of state (EOS). Phonon velocities were determined with sine dispersion relations. Cij values were obtained by fitting phonon velocities and densities to the Christoffel equation. We found that the obtained Cijs were in good
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Effects of Fe and Al incorporations on the bridgmanite–postperovskite coexistence domain CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Xianlong Wang, Taku Tsuchiya, Zhi Zeng
Abstract The postperovskite phase transition of Fe and Al-bearing MgSiO3 bridgmanite, the most aboundant mineral in the Earth's lower mantle, is believed to be a key to understanding seismological observations in the D″ layer, e.g., the discontinuous changes in seismic wave velocities. Experimentally reported phase transition boundaries of Fe and Al-bearing bridgmanite are currently largely controversial
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Electrical resistivity of fcc phase iron hydrides at high pressures and temperatures CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Kenji Ohta, Sho Suehiro, Kei Hirose, Yasuo Ohishi
Abstract We measured the electrical resistivity of face-centered-cubic (fcc) structured iron hydrides at high pressures up to 65 GPa and high temperatures in a laser-heated diamond anvil cell. The results indicate that the resistivity of stoichiometric fcc FeHx (x ∼ 1.0) is smaller than that of fcc Fe at the same pressure and temperature conditions. The same behavior was also observed in fcc FeNiHx
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On the implications of the coupled evolution of the deep planetary interior and the presence of surface ocean water in hydrous mantle convection CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Takashi Nakagawa, Hikaru Iwamori
Abstract We investigate the influence of the deep mantle water cycle incorporating dehydration reactions with subduction fluxes and degassing events on the thermal evolution of the Earth as a consequence of core–mantle thermal coupling. Since, in our numerical modeling, the mantle can have ocean masses ∼12 times larger than the present-day surface ocean, it seems that more than 13 ocean masses of water
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A waveguide-based flexible CO2-laser heating system for diamond-anvil cell applications CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Alexander Kurnosov, Hauke Marquardt, Leonid Dubrovinsky, Vasily Potapkin
Abstract Fiber-based laser heating systems offer high flexibility and are increasingly used in high-pressure/high-temperature research. Previous fiber-based laser heating systems were based on lasers delivering radiation with 1-μm wavelength that show unfavorable heating characteristics for many sample materials. We report on the development and first experiments of a waveguide (fiber)-based CO2-laser
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High-pressure and high-temperature stability of chlorite and 23-Å phase in the natural chlorite and synthetic MASH system CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Nao Cai, Toru Inoue
Abstract A series of experiments was conducted on the decomposition of natural and chemically mixed chlorites to examine the stable hydrous phases in the MgO–FeO–Al2O3–SiO2–H2O (MFASH) system under 5–12 GPa and 700–1100 °C. The upper pressure and temperature limits of the stability region of chlorite are consistent with those observed in previous studies. The hydrous aluminum bearing pyroxene (phase
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Density variations of Cr-rich garnets in the upper mantle inferred from the elasticity of uvarovite garnet CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Steeve Gréaux, Akihiro Yamada
Abstract The thermoelastic parameters of Ca3Cr2Si3O12 uvarovite garnet were examined in situ at high pressure up to 13 GPa and high temperature up to 1100 K by synchrotron radiation energy-dispersive X-ray diffraction within a 6-6-type multi-anvil press apparatus. A least-square fitting of room T data to a third-order Birch–Murnaghan (BM3) EoS yielded K0 = 164.2 ± 0.7 GPa, V0 = 1735.9 ± 0.3 A3 (K’0
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Penetration of molten iron alloy into the lower mantle phase CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Takashi Yoshino
Abstract The core–mantle boundary is the only interface where the metallic core and the silicate mantle interact physically and chemically. Many geophysical anomalies such as low shear velocity and high electrical conductivity have been observed at the bottom of the mantle. Perturbations in the Earth's rotation rate at decadal time periods require the existence of a thin conductive layer with a conductance
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Sound velocity and density of liquid Ni68S32 under pressure using ultrasonic and X-ray absorption with tomography methods CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Hidenori Terasaki, Keisuke Nishida, Satoru Urakawa, Yusaku Takubo, Soma Kuwabara, Yuta Shimoyama, Kentaro Uesugi, Yoshio Kono, Akihisa Takeuchi, Yoshio Suzuki, Yuji Higo, Tadashi Kondo
Comptes Rendus Geoscience - In Press.Proof corrected by the author Available online since mardi 13 novembre 2018
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Bulk modulus of Fe-rich olivines corrected for non-hydrostaticity CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Frédéric Béjina, Misha Bystricky, Nicolas Tercé, Matthew L. Whitaker, Haiyan Chen
Abstract In situ X-ray diffraction was used to measure the isothermal bulk modulus at room conditions (KT0) of synthetic olivines with different iron contents. The chemical formulae of the olivine samples were ( Fe x , Mg 1 − x ) 2 Si O 4 with x = 0.45; 0.64; 0.82; 1, with 1% standard deviation (referenced as Fa45, Fa64, Fa82 and Fa100, respectively). All experiments were performed in the multi-anvil
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High-pressure yield strength of rocksalt structures using quartz Raman piezometry CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Bruno Reynard, Razvan Caracas, Hervé Cardon, Gilles Montagnac, Sébastien Merkel
Abstract The Raman frequencies of quartz are used to evaluate deviatoric stresses in rocksalt-structure media in diamond-anvil cell experiments to pressures up to 20 GPa. The piezospectroscopic effect in quartz is modeled by first-principles calculations. Non-hydrostatic stresses measured in halogen salts give yield strength estimates of 3 GPa in the B1 structure (NaCl), and 4.5 GPa for the B2 structure
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High-pressure single-crystal X-ray diffraction and synchrotron Mössbauer study of monoclinic ferrosilite CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Natalia V. Solomatova, Ayya Alieva, Gregory J. Finkelstein, Wolfgang Sturhahn, Michael B. Baker, Christine M. Beavers, Jiyong Zhao, Thomas S. Toellner, Jennifer M. Jackson
Comptes Rendus Geoscience - In Press.Proof corrected by the author Available online since samedi 4 aout 2018
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Thermodynamical constraints on the crystallization of a deep magma-ocean on Earth CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Denis Andrault
Comptes Rendus Geoscience - In Press.Proof corrected by the author Available online since dimanche 15 juillet 2018
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Sound velocity of Fe3C at high pressure and high temperature determined by inelastic X-ray scattering CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Suguru Takahashi, Eiji Ohtani, Tatsuya Sakamaki, Seiji Kamada, Hiroshi Fukui, Satoshi Tsutsui, Hiroshi Uchiyama, Daisuke Ishikawa, Naohisa Hirao, Yasuo Ohishi, Alfred Q.R. Baron
Abstract The sound velocity of Fe 3 C was measured at pressures from 33 to 86 GPa and at ambient and high temperatures up to 2300 K using inelastic X-ray scattering (IXS) from laser-heated samples in diamond anvil cells (DACs). The compressional velocity ( V P ) and density of Fe 3 C at room temperature were observed to follow a linear relationship (Birch's law). The temperature dependency of Birch's
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Trace-element characteristics of east–west mantle geochemical hemispheres CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Hikaru Iwamori, Hitomi Nakamura, Masaki Yoshida, Takashi Nakagawa, Kenta Ueki, Atsushi Nakao, Tatsuji Nishizawa, Satoru Haraguchi
Abstract Recent statistical analyses on the isotopic compositions of oceanic, arc, and continental basalts have revealed that the Earth's mantle is broadly divided into eastern and western hemispheres. The present study aimed to characterize the isotopically defined east–west geochemical hemispheres using trace-element concentrations. Basalt data with Rb, Sr, Nd, Sm, Pb, Th, and U in addition to the
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Simultaneous measurements of the two-dimensional distribution of infrared laser intensity and temperature in a single-sided laser-heated diamond anvil cell CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Kamil M. Bulatov, Pavel V. Zinin, Yulia V. Mantrova, Aleksey A. Bykov, Maksim I. Gaponov, Alexsandr S. Machikhin, Ivan A. Troyan, Igor B. Kutuza
Abstract In this report, we demonstrate that combining the laser heating system in a diamond anvil cell (LH-DAC) with a tandem acoustic-optical tunable filter (LH-DAC–TAOTF) allows for the simultaneous measurement of (a) the relative infrared (IR, 1070 nm) power distribution on a specimen surface in the DAC; (b) the temperature distribution under laser heating of a specimen under high-pressure in a
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High-pressure generation in the Kawai-type multianvil apparatus equipped with tungsten-carbide anvils and sintered-diamond anvils, and X-ray observation on CaSnO 3 and (Mg,Fe)SiO 3 CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Daisuke Yamazaki, Eiji Ito, Takashi Yoshino, Noriyoshi Tsujino, Akira Yoneda, Hitoshi Gomi, Jaseem Vazhakuttiyakam, Moe Sakurai, Youyue Zhang, Yuji Higo, Yoshinori Tange
Abstract We extended the attainable pressure of the Kawai-type multianvil apparatus to 71.3 GPa and 120.3 GPa at room temperature by equipping it with tungsten carbide (WC) and sintered diamond (SD) cubic anvils, respectively. In the experiments with WC anvils, pressure decreased largely, ΔP ∼−20 GPa, on heating from room temperature to 1500 K. In the experiments with SD anvils, pressure also dropped
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Pressure-induced dehydration of dioptase: A single-crystal X-ray diffraction and Raman spectroscopy study CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Fei Qin, Xiang Wu, Shan Qin, Dongzhou Zhang, Vatali B. Prakapenka, Steven D. Jacobsen
Abstract We present a synchrotron-based, single-crystal X-ray diffraction and Raman spectroscopy study of natural green dioptase (Cu6Si6O18·6H2O) up to ∼30 GPa at room temperature. The lattice parameters of dioptase exhibit continuous compression behavior up to ∼14.5 GPa, whereupon a structural transition is observed. Pressure–volume data below 14.5 GPa were fitted to a second-order Birch–Murnaghan
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Preface. Some remarks on the evolution of mineral physics over the past 40 years CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Jean-Paul Poirier
Comptes Rendus Geoscience - In Press.Proof corrected by the author Available online since mardi 22 mai 2018
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High pressure generation in Kawai-type multianvil apparatus using nano-polycrystalline diamond anvils CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Tetsuo Irifune, Takehiro Kunimoto, Toru Shinmei, Yoshinori Tange
Abstract Nano-polycrystalline diamond cubes with an edge length of 6 mm have been used as anvils for Kawai-type multianvil apparatus. The maximum pressure of ∼88 GPa was confirmed based on in situ X-ray diffraction measurements using nano-polycrystalline diamond anvils with a truncation of 1.0 mm, which is more than 50% higher than the pressure (∼56 GPa) achieved at the same press load using sintered-diamond
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An upgraded and integrated large-volume high-pressure facility at the GeoSoilEnviroCARS bending magnet beamline of the Advanced Photon Source CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Tony Yu, Yanbin Wang, Mark L. Rivers, Stephen R. Sutton
Abstract GeoSoilEnviroCARS (GSECARS) is an earth-science-driven X-ray synchrotron facility at the Advanced Photon Source of the Argonne National Laboratory. As a national user facility, we provide users with access to the high-brilliance hard X-rays from this third-generation synchrotron light source. The multi-anvil, large-volume high-pressure facility at the bending magnet beamline (13-BM-D) runs
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Combining ECCI and FIB milling techniques to prepare site-specific TEM samples for crystal defect analysis of deformed minerals at high pressure CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Nobuyoshi Miyajima, Tommaso Mandolini, Florian Heidelbach, Caroline Bollinger
Comptes Rendus Geoscience - In Press.Proof corrected by the author Available online since samedi 5 janvier 2019
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Structural phase transitions in aluminium above 320 GPa CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Guillaume Fiquet, Chandrabhas Narayana, Christophe Bellin, Abhay Shukla, Imène Estève, Art L. Ruoff, Gaston Garbarino, Mohamed Mezouar
Abstract With the application of pressure, a material decreases in volume as described in its equation of state, which is governed by energy considerations. At extreme pressures, common materials are thus expected to transform into new dense phases with extremely compact atomic arrangements that may also have unusual physical properties. For aluminium, first principle calculations have consistently
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Synthesis and characterization of polycrystalline KAlSi3O8 hollandite [liebermannite]: Sound velocities vs. pressure to 13 GPa at room temperature CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Ting Chen, Gabriel D. Gwanmesia, Lars Ehm, Charles Le Losq, Daniel R. Neuville, Brian L. Phillips, Baosheng Li, Robert C. Liebermann
Comptes Rendus Geoscience - In Press.Proof corrected by the author Available online since lundi 17 decembre 2018
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Composition and pressure dependence of lattice thermal conductivity of (Mg,Fe)O solid solutions CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Akira Hasegawa, Kenji Ohta, Takashi Yagi, Kei Hirose, Yoshiyuki Okuda, Tadashi Kondo
Abstract We measured the lattice thermal conductivities of Fe0.98O wustite and iron-rich (Mg,Fe)O magnesiowustite using the pulsed light heating thermoreflectance technique with a diamond anvil cell up to 61 GPa at 300 K. We found that the thermal conductivity of wustite does not show a monotonic increase as a function of pressure, contrary to that of MgO periclase. Rocksalt (B1) to rhombohedral B1
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Resistivity saturation in liquid iron–light-element alloys at conditions of planetary cores from first principles computations CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Fabian Wagle, Gerd Steinle-Neumann, Nico de Koker
Abstract We present a comprehensive analysis of electrical resistivity for liquid Fe–Si, Fe–S, and Fe–O alloys from first principles computations, covering the pressure/temperature conditions and major light element candidates inside the cores of terrestrial planets. By fitting optical conductivity with the Drude formula, we explicitly calculate the effective electron mean free path, and show that
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Olivine intergranular plasticity at mantle pressures and temperatures CR Geosci. (IF 1.4) Pub Date : 2019-02-01 Paul Raterron, Caroline Bollinger, Sébastien Merkel
Abstract The ductile behavior of olivine-rich rocks is critical to constrain thermal convection in the Earth's upper mantle. Classical olivine flow laws for dislocation or diffusion creep fail to explain the fast post-seismic surface displacements observed by GPS, which requires a much weaker lithosphere than predicted by classical laws. Here we compare the plasticity of olivine aggregates deformed
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Paleoclimatic implications of hydrogen and oxygen isotopic compositions of Cretaceous–Tertiary kaolins in the Douala Sub-Basin, Cameroon CR Geosci. (IF 1.4) Pub Date : 2019-01-01 Nenita Bukalo, Georges-Ivo Ekosse, John Odiyo, Jason Ogola
Abstract Increased interest in paleoenvironmental studies is a result of climatic changes occurring at present and predicted for the future. Such studies could be done using the stable isotope compositions (δ2H and δ18O) of kaolins, which provide knowledge on the paleoenvironmental conditions prevailing during the time of kaolinisation. In this study, the stable isotopic compositions of clay-size fraction
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Simulation of seismic-prospecting random noise in the desert by a Brownian-motion-based parametric modeling algorithm CR Geosci. (IF 1.4) Pub Date : 2019-01-01 Tie Zhong, Shuo Zhang, Yue Li, Baojun Yang
Abstract Random noise has a negative impact on seismic-prospecting record processing. An important step to improve the methods aimed at the attenuation of random noise is to scientifically characterize the properties of the noise. Numerical modeling is useful to understand the nature of the random noise. In this study, we present a Brownian-motion-based parametric modeling algorithm for the simulation
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Automatic correction and simplification of geological maps and cross-sections for numerical simulations CR Geosci. (IF 1.4) Pub Date : 2019-01-01 Pierre Anquez, Jeanne Pellerin, Modeste Irakarama, Paul Cupillard, Bruno Lévy, Guillaume Caumon
Abstract Incorporating prior geological knowledge in geophysical process models often meets practical meshing challenges and raises the question of how much detail is to be included in the geometric model. We introduce a strategy to automatically repair and simplify geological maps, geological cross-sections and the associated meshes while preserving elementary consistency rules. To identify features