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10 results on '"Bulk composition"'

1. Parental magma of the Skaergaard intrusion: constraints from melt inclusions in primitive troctolite blocks and FG-1 dykes

Author

Jakobsen, Jakob K., Tegner, Christian, Brooks, C. Kent, Kent, Adam J., Lesher, Charles E., Nielsen, Troels F., and Wiedenbeck, Michael

Subjects
Earth Sciences, Mineralogy, Mineral Resources, Geology, Skaergaard intrusion, Melt inclusions, Bulk composition, Parental magma, East Greenland
Abstract

Troctolite blocks with compositions akin to the Hidden Zone are exposed in a tholeiitic dyke cutting across the Skaergaard intrusion, East Greenland. Plagioclase in these blocks contains finely crystallised melt inclusions that we have homogenised to constrain the parental magma to 47.4–49.0 wt.% SiO2, 13.4–14.9 wt.% Al2O3 and 10.7–14.1 wt.% FeOT. These compositions are lower in FeOT and higher in SiO2 than previous estimates and have distinct La/SmN and Dy/YbN ratios that link them to the lowermost volcanic succession (Milne Land Formation) of the regional East Greenland flood basalt province. New major- and trace element compositions for the FG-1 dyke swarm, previously taken to represent Skaergaard magmas, overlap with the entire range of the regional flood basalt succession and do not form a coherent suite of Skaergaard like melts. These dykes are therefore re-interpreted as feeder dykes throughout the main phase of flood basalt volcanism.

Published
2010

2. On the principal building blocks of Mars and Earth

Author

Amir Khan and Christian Liebske

Subjects
Solar System, Planetesimal, 010504 meteorology & atmospheric sciences, Astronomy and Astrophysics, Mars Exploration Program, Mars, Earth, Oxygen isotopes, Nucleosynthetic isotopes, Chondrites, Bulk composition, 01 natural sciences, Mantle (geology), Physics::Geophysics, Astrobiology, Space and Planetary Science, Chondrite, Planet, Physics::Space Physics, 0103 physical sciences, Terrestrial planet, Astrophysics::Earth and Planetary Astrophysics, 010303 astronomy & astrophysics, Achondrite, Geology, 0105 earth and related environmental sciences
Abstract

The terrestrial planets are believed to have been formed from primitive material sampling a broad region of the inner solar system. Several meteoritic mixing models attempting to reconcile isotopic characteristics of Mars and Earth have been proposed, but, because of the inherent non-uniqueness of these solutions, additional independent observations are required to resolve the question of the primary building blocks of the terrestrial planets. Here, we consider existing isotopic measurements of Δ ′ 17 O, ϵ48Ca, ϵ50Ti, ϵ54Cr, ϵ62Ni, and ϵ84Sr for primitive chondrites and differentiated achondrites and mix these stochastically to reproduce the isotopic signatures of Mars and Earth. For both planets we observe ∼ 105 unique mixing solutions out of 108 random meteoritic mixtures, which are categorised into distinct clusters of mixtures using principal component analysis. The large number of solutions implies that isotopic data alone are insufficient to resolve the building blocks of the terrestrial planets. To further discriminate between isotopically valid mixtures, each mixture is converted into a core and mantle component via mass balance for which geophysical properties are computed and compared to observations. For Mars, the geophysical parameters include mean density, mean moment of inertia, and tidal response, whereas for Earth upper mantle Mg/(Mg+Fe) ratio and core size are employed. The results show that Mars requires an oxidised, FeO-rich differentiated object next to chondritic material as main building blocks. In contrast, Earth's origin remains enigmatic. From a redox perspective, it appears inescapable that enstatite chondrite-like matter constitutes a dominant proportion of the building blocks from which Earth is made. The apparent need for compositionally distinct building blocks for Mars and Earth suggests that dissimilar planetesimal reservoirs were maintained in the inner Solar System during accretion.

Published
2019

3. SEIS: Insight’s Seismic Experiment for Internal Structure of Mars

Author

L. Perrin, C. Bonjour, N. Toulemont, Jean-Luc Berenguer, G. Perez, James Wookey, A. G. Mukherjee, Hallie Gengl, Edward A. Miller, Delphine Faye, Antoine Mocquet, J. Sicre, B. Vella, D. Dilhan, C. Larigauderie, John C. Bousman, M. Nonon, Y. Bennour, Véronique Dehant, Jeffrey W. Umland, T. Nebut, D. Hernandez, M. Eberhardt, Vincent Conejero, Rudolf Widmer-Schnidrig, Philippe Lognonné, G. de los Santos, S. A. D’Agostino, Savas Ceylan, Justin N. Maki, G. Aveni, P. Revuz, S. de Raucourt, C. Aicardi, Clément Perrin, A. K. Delahunty, Constanza Pardo, Domenico Giardini, L. Pou, Robert J. Calvet, D. Savoie, O. Robert, V. Gharakanian, S. Ben Charef, Constantinos Charalambous, Kerry Klein, S. M. Madzunkov, J. M. Desmarres, Sue Smrekar, S. B. Calcutt, F. Grinblat, Nicholas A Teanby, I. M. Standley, Naomi Murdoch, Brigitte Knapmeyer-Endrun, M. Deleuze, C. Doucet, William T. Pike, Tom L. Hoffman, F. Mialhe, Cecily M. Sunday, J. Paredes-Garcia, Matthew P. Golombek, P. Bhandari, Huafeng Liu, B. Pouilloux, E. Blanco, Gabriel Pont, Simon Stähler, M. E. Johnson, Nicolas Verdier, L. Luno, Ned W. Ferraro, R. Perez, Mélanie Drilleau, F. Ijpelaan, B. Lecomte, M. van Driel, A. Sauron, I. Estève, Mark P. Panning, David Mimoun, P. A. Dandonneau, B. Kenda, T. Gabsi, W. Raff, P. Boutte, T. Warren, Joan Ervin, Fabian Euchner, S. Tillier, K. J. Hurst, Stephen Larson, Davor Mance, Mark A. Wieczorek, J. A. Rodriguez-Manfredi, Justin Lin, Jaime Singer, M. Monecke, Robert W. Denise, E.-P. Miettinen, Maren Böse, E. Locatelli, I. Savin de Larclause, J. Gagnepain-Beyneix, L. Khachikyan, Philippe Laudet, T. Carlier, Alexander E. Stott, Neil Bowles, Brian Bone, C. Imbert, Sharon Kedar, A. Rosak, Fred Calef, O. Pot, O. M. Avalos, P. Labrot, Jeroen Tromp, Lucile Fayon, C. Moreau, J. Baroukh, William B. Banerdt, M. Bierwirth, Ranah Irshad, M. André, Christopher T. Russell, S. L. Marshall, M. Parise, J.-R. Meyer, P. Pasquier, N. Faye-Refalo, Ingrid Daubar, M. A. Balzer, R. Gonzalez, M. Hetzel, K. Brethomé, Y. Pahn, Raphaël F. Garcia, J. tenPierick, U. R. Christensen, Farah Alibay, Renee Weber, Robert G. Deen, Eléonore Stutzmann, J. Temple, Don Banfield, A. Bouisset, D. B. Klein, A. Borrien, Ashitey Trebi-Ollennu, R. Llorca-Cejudo, L. J. Facto, J. M. Mouret, Alexis Paillet, Peter Zweifel, P. Bruneau, Catherine L. Johnson, C. Brysbaert, J. E. Feldman, A. Kramer, Luigi Ferraioli, Jane Hurley, Taichi Kawamura, Nicholas Onufer, W. Kühne, Eric Beucler, Amir Khan, M. Sodki, L. Kerjean, A. Sylvestre-Baron, C. Desfoux, C. Yana, John Clinton, J. R. Willis, Juan Villalvazo, Pierre Delage, Mihail P. Petkov, M. C. Wallace, T. Camus, Ioannis G. Mikellides, Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Institute of Geophysics [ETH Zürich], Department of Earth Sciences [Swiss Federal Institute of Technology - ETH Zürich] (D-ERDW), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Department of Mechanical Engineering [Imperial College London], Imperial College London, Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Centre National d'Études Spatiales [Toulouse] (CNES), Geological Institute (ETHZ), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), University of Oxford, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), NASA Marshall Space Flight Center (MSFC), 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), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Laboratoire de Mecanique des Fluides et d'Acoustique (LMFA), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), 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)-Centre National de la Recherche Scientifique (CNRS), Department of Atmospheric, Oceanic and Planetary Physics [Oxford] (AOPP), Advanced Technology and Research, Space Science and Technology Department [Didcot] (RAL Space), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC)-Science and Technology Facilities Council (STFC), Clarendon Laboratory [Oxford], Huazhong University of Science and Technology [Wuhan] (HUST), Kinemetrics, Cornell University [New York], Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), University of California [Los Angeles] (UCLA), University of California (UC), Institut of GeophysicsETHZ, Géoazur (GEOAZUR 7329), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Swiss Seismological Service, Royal Observatory of Belgium [Brussels] (ROB), Géotechnique (cermes), Laboratoire Navier (navier umr 8205), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), University of British Columbia (UBC), Planetary Science Institute [Tucson] (PSI), Laboratoire national de métrologie et d'essais - Systèmes de Référence Temps-Espace (LNE - SYRTE), Systèmes de Référence Temps Espace (SYRTE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), University of Bristol [Bristol], Department of Geosciences [Princeton], Princeton University, Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Universität Stuttgart [Stuttgart], School of Earth Sciences [Bristol], Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Université Paris Diderot - Paris 7 (UPD7)-IPG PARIS-Institut national des sciences de l'Univers (INSU - CNRS), Max-Planck-Institut für Sonnensystemforschung (MPS), University of Oxford [Oxford], Max Planck Institute for Solar System Research (MPS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-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)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), University of California, INSTITUT OF GEOPHYSICS ETHZ, Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Karlsruhe Institute of Technology and Stuttgart University, Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), California Institute of Technology (CALTECH)-NASA, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Département Electronique, Optronique et Signal (DEOS), Department of Earth Sciences [ETH Zürich] (D-ERDW), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Laboratoire de Planétologie et Géodynamique UMR6112 (LPG), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Nantes - Faculté des Sciences et des Techniques, Université de Nantes (UN)-Université de Nantes (UN)-Université d'Angers (UA), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Cornell University, Consejo Superior de Investigaciones Científicas [Spain] (CSIC)-Instituto Nacional de Técnica Aeroespacial (INTA), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA), Royal Observatory of Belgium [Brussels], PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), School of Earth Sciences University of Bristol, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Observatoire de la Côte d'Azur, and Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Seismometer, DISSIPATIVE FACTOR, 010504 meteorology & atmospheric sciences, FREE OSCILLATIONS, BULK COMPOSITION, Mars, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Astronomy & Astrophysics, 01 natural sciences, Transfer function, Article, NETWORK SCIENCE, Autre, 0103 physical sciences, 0201 Astronomical and Space Sciences, INTERIOR STRUCTURE, ddc:530, Ground segment, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, InSight, Data processing, Science & Technology, Physics, Bandwidth (signal processing), Mars seismology, Astronomy and Astrophysics, Moment magnitude scale, SINGLE-STATION, THERMAL EVOLUTION, Mars Exploration Program, Geodesy, Space and Planetary Science, Physical Sciences, WAVE PROPAGATION, ELYSIUM PLANITIA, [SDU.OTHER]Sciences of the Universe [physics]/Other, Robotic arm, SEIS, Geology, METEORITE IMPACTS
Abstract

By the end of 2018, 42 years after the landing of the two Viking seismometers on Mars, InSight will deploy onto Mars’ surface the SEIS (Seismic Experiment for Internal Structure) instrument; a six-axes seismometer equipped with both a long-period three-axes Very Broad Band (VBB) instrument and a three-axes short-period (SP) instrument. These six sensors will cover a broad range of the seismic bandwidth, from 0.01 Hz to 50 Hz, with possible extension to longer periods. Data will be transmitted in the form of three continuous VBB components at 2 sample per second (sps), an estimation of the short period energy content from the SP at 1 sps and a continuous compound VBB/SP vertical axis at 10 sps. The continuous streams will be augmented by requested event data with sample rates from 20 to 100 sps. SEIS will improve upon the existing resolution of Viking’s Mars seismic monitoring by a factor of ∼2500 at 1 Hz and ∼200000 at 0.1 Hz. An additional major improvement is that, contrary to Viking, the seismometers will be deployed via a robotic arm directly onto Mars’ surface and will be protected against temperature and wind by highly efficient thermal and wind shielding. Based on existing knowledge of Mars, it is reasonable to infer a moment magnitude detection threshold of Mw∼3 at 40∘ epicentral distance and a potential to detect several tens of quakes and about five impacts per year. In this paper, we first describe the science goals of the experiment and the rationale used to define its requirements. We then provide a detailed description of the hardware, from the sensors to the deployment system and associated performance, including transfer functions of the seismic sensors and temperature sensors. We conclude by describing the experiment ground segment, including data processing services, outreach and education networks and provide a description of the format to be used for future data distribution., Space Science Reviews, 215 (1), ISSN:1572-9672, ISSN:0038-6308

Published
2019
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4. Crystallization of the lunar magma ocean and the primordial mantle-crust differentiation of the Moon

Author

Timothy L. Grove, Francois Holtz, Bernard Charlier, and Olivier Namur

Subjects
Geochemistry & Geophysics, Experimental petrology, 010504 meteorology & atmospheric sciences, GIANT IMPACT, BULK COMPOSITION, INTERNAL STRUCTURE, 010502 geochemistry & geophysics, Anorthosite, 01 natural sciences, Mantle (geology), law.invention, chemistry.chemical_compound, PLAGIOCLASE-FLOTATION, CUMULATE OVERTURN, Geochemistry and Petrology, law, Graphite, Crystallization, Petrology, 0105 earth and related environmental sciences, LAPAZ ICEFIELD 02205, FRACTIONAL CRYSTALLIZATION, Science & Technology, Piston cylinder, Crust, Liquid line of descent, Silicate, FERROAN ANORTHOSITES, TERRESTRIAL PLANETS, chemistry, Lunar magma ocean, Physical Sciences, CHEMICAL-MODEL, Lunar crust, Mantle, Phase equilibria, Geology
Abstract

© 2018 Elsevier Ltd We present crystallization experiments on silicate melt compositions related to the lunar magma ocean (LMO) and its evolution with cooling. Our approach aims at constraining the primordial internal differentiation of the Moon into mantle and crust. We used graphite capsules in piston cylinder (1.35–0.80 GPa) and internally-heated pressure vessels (

Published
2018

5. Magnitude Scales for Marsquakes

Author

Domenico Giardini, Maren Böse, Fabian Euchner, John Clinton, Amir Khan, Philippe Lognonné, Martin van Driel, Simon Stähler, Savas Ceylan, William B. Banerdt, Swiss Fed Inst Technol, Swiss Seismol Serv, Sonneggstr 5, CH-8092 Zurich, Switzerland, Swiss Fed Inst Technol, Inst Geophys, Sonneggstr 5, CH-8092 Zurich, Switzerland, Swiss Fed Inst Technol, Swiss Seismol Serv SED, Sonneggstr 5, CH-8092 Zurich, Switzerland, Institut de Physique du Globe de Paris (IPGP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), CALTECH, Jet Prop Lab, M-S 321-B60,4800 Oak Grove Dr, Pasadena, CA 91109 USA, and Swiss National Science Foundation-Agence Nationale Recherche (SNF-ANR) 157133 Swiss National Supercomputing Center (CSCS) sm682

Subjects
010504 meteorology & atmospheric sciences, MODELS, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Magnitude (mathematics), BULK COMPOSITION, MARS SEISMICITY, 010502 geochemistry & geophysics, 01 natural sciences, NOISE, Background noise, Geochemistry and Petrology, EARTH, LOCATION, ENERGY-RELEASE, Seismogram, 0105 earth and related environmental sciences, SEISMOGRAMS, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Attenuation, SINGLE-STATION, Mars Exploration Program, INSIGHT MISSION, Geodesy, Geophysics, Amplitude, 13. Climate action, [SDU]Sciences of the Universe [physics], Seismic moment, Noise (radio), Geology
Abstract

International audience; In anticipation of the upcoming 2018 InSight (Interior exploration using Seismic Investigations, Geodesy and Heat Transport) Discovery mission to Mars, we calibrate magnitude scales for marsquakes that incorporate state-of-the-art knowledge on Mars interior structure and the expected ambient and instrumental noise. We regress magnitude determinations of 2600 randomly distributed marsquakes, simulated with a spectral element method for 13 published 1D structural models of Mars' interior. The continuous seismic data from InSight will be returned at 2 samples per second. To account for this limited bandwidth as well as for the expected noise conditions on Mars, we define and calibrate six magnitude scales: (1) local Mars magnitude M-L(Ma) at a period of 3 s for marsquakes at distances of up to 10 degrees; (2) P-wave magnitude m(b)(Ma); (3) S-wave magnitude m(bS)(Ma) each defined at a period of 3 s and calibrated for distances from 5 degrees to 100 degrees; (4) surface-wave magnitude M-s(Ma) defined at a period of 20 s, as well as (5) moment magnitudes M-FB(Ma); and (6) M-F(Ma) computed from the low-frequency (10-100 s) plateau of the displacement spectrum for either body waves or body and surface waves, respectively; we calibrate scales (4)-(6) for distances from 5 degrees to 180 degrees. We regress stable calibrations of the six scales with respect to the seismic moment magnitude at M-w 5.5 by correcting filtered phase amplitudes for attenuation with distance and source depth. Expected errors in epicentral distance and in source depth (25% and 20 km, respectively) translate into magnitude errors of 0.1-0.3 units. We validate our magnitude relations with an independent test dataset of 2600 synthetic marsquakes (1.0 15 degrees are expected to be hidden in the Mars background noise and will likely not be detectable.

Published
2018
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6. Automated Quantitative Mineralogy Applied to Metamorphic Rocks

Author

Nynke Keulen, Shaun Graham, and Sebastian Næsby Malkki

Subjects
zeiss mineralogic, lcsh:QE351-399.2, 010504 meteorology & atmospheric sciences, Metamorphic rock, Mineralogy, 010502 geochemistry & geophysics, 01 natural sciences, element concentration map, Matrix (geology), automated quantitative mineralogy (aqm), bulk composition, feret angle, fiskenæsset complex, visualization, 0105 earth and related environmental sciences, grain size, lcsh:Mineralogy, Mineral, Pixel, Orientation (computer vision), Geology, mineral association, Geotechnical Engineering and Engineering Geology, Grain size, Visualization, Quantitative mineralogy, scanning electron microscopy
Abstract

The ability to apply automated quantitative mineralogy (AQM) on metamorphic rocks was investigated on samples from the Fisken&aelig, sset complex, Greenland. AQM provides the possibility to visualize and quantify microstructures, minerals, as well as the morphology and chemistry of the investigated samples. Here, we applied the ZEISS Mineralogic software platform as an AQM tool, which has integrated matrix corrections and full quantification of energy dispersive spectrometry data, and therefore is able to give detailed chemical information on each pixel in the AQM mineral maps. This has been applied to create mineral maps, element concentration maps, element ratio maps, mineral association maps, as well as to morphochemically classify individual minerals for their grain shape, size, and orientation. The visualization of metamorphic textures, while at the same time quantifying their textures, is the great strength of AQM and is an ideal tool to lift microscopy from the qualitative to the quantitative level.

Published
2020
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7. Chemical analysis of iron meteorites using a Hand-Held X-Ray Fluorescence spectrometer

Author

Luigi Folco, Massimo D'Orazio, and Maurizio Gemelli

Subjects
Physics, Metal alloy, Hand held, iron meteorites, Analytical chemistry, hand-held XRF, X-ray fluorescence, Mineralogy, Geology, Cosmochemistry, Meteorite, Geochemistry and Petrology, cosmochemistry, bulk composition, Chemical composition
Abstract

We evaluate the performance of a hand-held XRF(HHXRF) spectrometer for the bulk analysis of ironmeteorites. Analytical precision and accuracy were testedon metal alloy certified reference materials and ironmeteorites of known chemical composition. With minimalsample preparation (i.e., flat or roughly polished surfaces)HHXRF allowed the precise and accurate determinationof most elements heavier than Mg, with concentrations> 0.01% m/m in metal alloy CRMs, and of majorelements Fe and Ni and minor elements Co, P and S(generally ranging from 0.1 to 1% m/m) in ironmeteorites. In addition, multiple HHXRF spot analysescould be used to determine the bulk chemical composi-tion of iron meteorites, which are often characterised bysulfide and phosphide accessory minerals. In particular, itwas possible to estimate the P and S bulk contents, whichare of critical importance for the petrogenesis andevolution of Fe-Ni-rich liquids and iron meteorites. Thisstudy thus validates HHXRF as a valuable tool for use inmeteoritics, allowing the rapid, non-destructive (a) iden-tification of the extraterrestrial origin of metallic objects(i.e., archaeological artefacts); (b) preliminary chemicalclassification of iron meteorites; (c) identification ofmislabelled/unlabelled specimens in museums and pri-vate collections and (d) bulk analysis of iron meteorites.Keywords: hand-held XRF, iron meteorites, bulk composition,cosmochemistry.Nous evaluons la performance d’un spectrometre por-table XRF (HHXRF) pour l’analyse chimique globale demeteorites de fer. La precision analytique et l’exactitudeont ete testees sur des alliages de metaux de referencecertifies et des meteorites de fer de composition chimiqueconnue. Avec une preparation minimale de l’echantillon(c’est a dire avec des surfaces plates ou plus ou moinspolies) l’HHXRF a permis la determination precise etexacte de la plupart des elements plus lourds que le Mg,et presentant des concentrations superieures a 0,01% m/m dans les alliages de metaux de reference certifies, etdes elements majeurs Fe et Ni et mineurs Co, P et S (allantgeneralement de 0,1 a1%m/m) dans les meteorites defer. En outre, des analyses ponctuelles multiples HHXRFpeuvent ^etre utilis ees pour determiner la compositionchimique globale de meteorites de fer, qui sont souventcaracterisees par la presence de mineraux accessoires detype sulfures et phosphures. En particulier, il a ete possibled’estimer les teneurs en P et S, qui sont d’une importancecruciale pour la comprehension de la petrogenese et del’evolution des liquides riches en Fe-Ni et des meteoritesde fer. Cette etude valide donc l’HHXRF comme un outilprecieux pour l’etude des meteorites, permettant unerapides et non-destructive (a) identification rapide del’origine extraterrestre des objets metalliques (versus lesartefacts archeologiques); (b) classification chimiquepreliminaire des meteorites de fer; (c) identification desspecimens mal etiquetes/non identifies dans les museeset les collections privees et (d) analyse globale demeteorites de fer.Mots-cles : XRF portable, meteorites de fer, composition

Published
2014

8. Physical state of the deep interior of the CoRoT-7b exoplanet

Author

Tina Rückriemen, Frank Sohl, F.W. Wagner, and Heike Rauer

Subjects
Convection, melting, planets and satellites, FOS: Physical sciences, magnetic fields, Earth-like planets, Mantle (geology), Planet, Thermal, Core–mantle boundary, bulk composition, equation of state, Earth and Planetary Astrophysics (astro-ph.EP), formation, Astronomy and Astrophysics, Geophysics, thermal state, Exoplanet, interior structure, interiors, CoRoT-7b, Heat flux, exoplanets, Space and Planetary Science, internal dynamics, Terrestrial planet, Astrophysics::Earth and Planetary Astrophysics, super-Earth, Geology, Astrophysics - Earth and Planetary Astrophysics
Abstract

The present study takes the CoRoT-7b exoplanet as an analogue for massive terrestrial planets to investigate conditions, under which intrinsic magnetic fields could be sustained in liquid cores. We examine the effect of depth-dependent transport parameters (e.g., activation volume of mantle rock) on a planet's thermal structure and the related heat flux across the core mantle boundary. For terrestrial planets more massive than the Earth, our calculations suggest that a substantial part of the lowermost mantle is in a sluggish convective regime, primarily due to pressure effects on viscosity. Hence, we find substantially higher core temperatures than previously reported from parameterized convection models. We also discuss the effect of melting point depression in the presence of impurities (e.g., sulfur) in iron-rich cores and compare corresponding melting relations to the calculated thermal structure. Since impurity effects become less important at the elevated pressure and temperature conditions prevalent in the deep interior of CoRoT-7b, iron-rich cores are likely solid, implying that a self-sustained magnetic field would be absent., 4 pages, 3 figures. IAU 276 Proceedings

Published
2010

9. Interior structure models of terrestrial exoplanets and application to CoRoT-7b

Author

Matthias Grott, F.W. Wagner, Heike Rauer, Hauke Hussmann, and Frank Sohl

Subjects
Mineral, melting, CoRot-7b, Energy balance, Astronomy and Astrophysics, Silicate, Exoplanet, Astrobiology, interiors, chemistry.chemical_compound, chemistry, Space and Planetary Science, Planet, extrasolar planets, bulk composition, Structure of the Earth, Mass fraction, Geology, Earth (classical element), equation of state
Abstract

In this study, we model the internal structure of CoRoT-7b, considered as a typical extrasolar terrestrial planet, using mass and energy balance constraints. Our results suggest that the deep interior is predominantly composed of dry silicate rock, similar to the Earth's Moon. A central iron core, if present, would be relatively small and less massive (

Published
2010

10. Parental magma of the Skaergaard intrusion:constraints from melt inclusions in primitive troctolite autoliths and FG-1 dykes

Author

Christian Tegner, Michael Wiedenbeck, Troels F.D. Nielsen, Jakob K. Jakobsen, Adam J.R. Kent, Charles E. Lesher, and C. Kent Brooks

Subjects
Bulk composition, Skaergaard intrusion, Geochemistry, 550 - Earth sciences, Volcanism, engineering.material, Layered intrusion, Geochemistry and Petrology, Plagioclase, Melt inclusions, East Greenland, geography, geography.geographical_feature_category, Geology, Mineralogy, Parental magma, Geophysics, Mineral Resources, Volcano, Magma, engineering, Flood basalt, Earth Sciences
Abstract

Troctolite blocks with compositions akin to the Hidden Zone are exposed in a tholeiitic dyke cutting across the Skaergaard intrusion, East Greenland. Plagioclase in these blocks contains finely crystallised melt inclusions that we have homogenised to constrain the parental magma to 47.4–49.0 wt.% SiO2, 13.4–14.9 wt.% Al2O3 and 10.7–14.1 wt.% FeOT. These compositions are lower in FeOT and higher in SiO2 than previous estimates and have distinct La/SmN and Dy/YbN ratios that link them to the lowermost volcanic succession (Milne Land Formation) of the regional East Greenland flood basalt province. New major- and trace element compositions for the FG-1 dyke swarm, previously taken to represent Skaergaard magmas, overlap with the entire range of the regional flood basalt succession and do not form a coherent suite of Skaergaard like melts. These dykes are therefore re-interpreted as feeder dykes throughout the main phase of flood basalt volcanism.

Published
2010
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