137 results on '"Luigi Folco"'
Search Results
2. Possible shock-induced crystallization of skeletal quartz from supercritical SiO2-H2O fluid: A case study of impact melt from Kamil impact crater, Egypt
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Luigi Folco, Falko Langenhorst, and Agnese Fazio
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silica polymorphs ,Shock metamorphism ,Geology ,Shock metamorphism, silica polymorphs, impact craters, Kamil Crater ,Supercritical fluid ,law.invention ,Shock (mechanics) ,impact craters ,Impact crater ,law ,Kamil Crater ,Crystallization ,Composite material ,Quartz - Abstract
Since its discovery, the Kamil crater (Egypt) has been considered a natural laboratory for studying small-scale impact cratering. We report on a previously unknown shock-related phenomenon observed in impact melt masses from Kamil; that is, the shock-triggered formation of skeletal quartz aggregates from silica-rich fluids. These aggregates are unshocked and characterized by crystallographically oriented lamellar voids and rounded vesicles. The distribution of the aggregates can be correlated with former H2O- and impurity-rich heterogeneities in precursor quartz; i.e., fluid inclusions. The heterogeneities acted as hot spots for local melting. Due to the presence of H2O and the high impact pressure and temperature, the formation of a localized supercritical fluid is plausible. Below the upper critical end point of the SiO2–H2O system (temperature
- Published
- 2021
3. Isotopic evolution of planetary crusts by hypervelocity impacts evidenced by Fe in microtektites
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M Van Ginneken, Bastien Soens, Eduardo Bolea-Fernandez, Natalia Artemieva, Stepan M. Chernonozhkin, Luigi Folco, Frank Vanhaecke, Ph. Claeys, C González de Vega, Joke Belza, Steven Goderis, Billy P. Glass, Matthew J. Genge, Chemistry, Analytical, Environmental & Geo-Chemistry, Faculty of Sciences and Bioengineering Sciences, and Earth System Sciences
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Solar System ,Multidisciplinary ,Science ,Condensation ,Evaporation ,General Physics and Astronomy ,General Chemistry ,Article ,General Biochemistry, Genetics and Molecular Biology ,Isotopic composition ,Astrobiology ,Physics::Geophysics ,Geochemistry ,Physics::Space Physics ,Hypervelocity ,Environmental science ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Early solar system ,Ejecta ,Volatiles ,Astrophysics::Galaxy Astrophysics - Abstract
Fractionation effects related to evaporation and condensation had a major impact on the current elemental and isotopic composition of the Solar System. Although isotopic fractionation of moderately volatile elements has been observed in tektites due to impact heating, the exact nature of the processes taking place during hypervelocity impacts remains poorly understood. By studying Fe in microtektites, here we show that impact events do not simply lead to melting, melt expulsion and evaporation, but involve a convoluted sequence of processes including condensation, variable degrees of mixing between isotopically distinct reservoirs and ablative evaporation during atmospheric re-entry. Hypervelocity impacts can as such not only generate isotopically heavy, but also isotopically light ejecta, with δ56/54Fe spanning over nearly 5‰ and likely even larger variations for more volatile elements. The mechanisms demonstrated here for terrestrial impact ejecta modify our understanding of the effects of impact processing on the isotopic evolution of planetary crusts., Fe isotopic composition of the distal ejecta of a terrestrial impact crater records both evaporation and condensation, refining the nature of the isotopic fractionation taking place during hypervelocity impacts in the Solar System.
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- 2021
4. Microtektites and glassy cosmic spherules from new sites in the Transantarctic Mountains, Antarctica
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Catherine M. Corrigan, Lauren E. Brase, James M.D. Day, Ralph P. Harvey, M. D. Suttle, E. Carrie McIntosh, and Luigi Folco
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Geophysics ,COSMIC cancer database ,Space and Planetary Science ,Geology ,Astrobiology - Published
- 2021
5. Water-rich C-type asteroids as early solar system carbonate factories
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Victoria Froh, Maitrayee Bose, Martin D. Suttle, Jacopo Nava, Luigi Folco, Lynda B. Williams, and Julie Castillo-Rogez
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Space and Planetary Science ,Astronomy and Astrophysics - Published
- 2023
6. Dust in the Upper Stratosphere Tracking Experiment and Retrieval: Exploring the Dust Reservoir of the Upper Stratosphere through Balloons
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Anna Musolino, Vincenzo Della Corte, Alessandra Rotundi, Zélia Dionnet, Luigi Folco, Vito Liuzzi, and Stefano Ferretti
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Dust in the Upper Stratosphere Tracking Experiment and Retrieval (DUSTER) aims to collect and characterize uncontaminated particles (In addition to DUSTER, only a few other attempts have been made for the collection of particles through balloons at altitude >30km [4,5]. The innovations brought by DUSTER include: (i) does not require sample manipulation after collection; (ii) guarantees low impact velocities between particles and the collector’s substrate; and (iii) a key factor, adopts a strict control protocol for the minimization of contamination [3,6]. On the collector (a holder with 13 TEM grids), directly exposed to the airflow, the particles remain stuck without the use of adhesive materials (dry collection). High-resolution images of the collector and the blank (similar to the collector but not exposed to the airflow) are acquired before and after the flight, to exclude from the count pre-existing particles [6,7].Five DUSTER launch campaigns successfully collected stratospheric particles. The most recent ones took place at the ESRANGE, Kiruna (Sweden), in 2019 and 2021. DUSTER sampled the stratosphere at an altitude of ~33km for ~5 hours over Lapland, and its collector and blank are currently under analysis. Up to now, the identified particles range from 0.1 to 150µm (latest data to be published). Morphologically, they can be classified as mineral fragments and aggregates, spherules, fungal spores [10], and a type-I cosmic spherule. EDX analyses have shown the occurrence of minerals like plagioclase, silica, fassaite, but also carbonates, CaO – all mineralogic phases present in CI and CM carbonaceous chondrites, unequilibrated ordinary chondrites, and comets [8]. The occurrence of CaO and carbon nanoparticles has been suggested to be a result of condensation after disaggregation of carbonates of extraterrestrial origin [11]. The ambitious goal of DUSTER is to become a reference collection for uncontaminated extraterrestrial particles available for scientific research – a unique and barely explored reservoir complementary to (micro)meteorites and IDPs available at the Earth’s surface. In general, the properties of solid and condensed dust in the upper stratosphere remain poorly known. Complete morphological and chemical characterization of particles collected at altitudes >30 km remains incidental with few exceptions, DUSTER will provide a record of the amount of solid aerosols, their size, shapes and chemical properties in the upper stratosphere, including particles less than 3 microns in size.Acknowledgement – ASI-INAF “Rosetta GIADA”,I/024/12/0 and 2019-33-HH.0; PRIN2015/MIUR; European Union's Horizon 2020 research and Innovation programme,No.730970.References – [1]Flynn, 1997. Nature,387, 248. [2]Brownlee 1985. Annu.Rev.Earth Planet.Sci., 13(1),147-173. [3]Della Corte & Rotundi, 2021. Elsevier,269-293. [4]Testa et al., 1990. Earth Planet.Sci.Lett., 98,287-302. [5]Wainwright et al., 2003. FEMS Microbiol.Lett., 218,161-165. [6]Della Corte et al., 2012. SpaceSci.Rev, 169,159-180. [7]Palumbo et al., 2008. Mem.Soc.Astron.Ital., 79,853. [8]Rietmeijer et al., 2016. Icarus, 266,217-234. [10]Della Corte et al., 2014. Astrobiology, 14(8),694-705. [11]Della Corte et al., 2013. TellusB: Chem.Phys.Meteorol.,65(1),1-12.
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- 2022
7. Non-equilibrium melting of partially differentiated asteroids: insights from partial melting experiments on L6 chondrite DAV01001
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Stefano Iannini Lelarge, Matteo Masotta, Luigi Folco, Lucia Mancini, and Lidia Pittarello
- Abstract
Planetary differentiation in small bodies is believed to be ruled by several partial end-states that were dominated by low degrees of partial melting and melt segregation, before arriving at the formation of rocky planets. Having a better understanding of non-equilibrium melting processes in undifferentiated chondritic materials is critical to characterize planetary differentiation processes and the formation of rocky planets and differentiated asteroids. In this context, partial melting experiments of natural chondrites can provide unique insights into the petrological evolution associated with early planetary differentiation of planetesimals. For this study, we performed partial melting experiments using fragments from the ordinary chondrite DAV01001. Experiments were performed in a piston-cylinder at 1 GPa pressure, at temperatures from 1100 to 1300 °C and for 24 hours run duration. Reducing conditions were imposed by the use of graphite capsules. The experimental products were analysed using electron microprobe and synchrotron radiation computed microtomography (SR-µCT).DAV01001 is an equilibrated L6 ordinary chondrite that has still visible relic chondrules and contains olivine (Fo75), low-Ca pyroxene (En77Fs21Wo2), high-Ca pyroxene (En47Fs8Wo45), albitic plagioclase (An13Ab81Or6), metal, troilite, chromite, and apatite. Upon heating, metal and troilite disappear at 1100 °C forming two immiscible phases, one made of pure metal with variable amounts of Ni, the other made of a metal-sulphide liquid of variable composition. Chromite starts melting at 1100 °C and disappears at 1300 °C. Silicatic melt forms already at 1100 °C as a result of the melting of plagioclase. With increasing temperature, the pyroxene and olivine begin to melt and shift the composition of the liquid towards trachy-andesitic (1200 °C) and basaltic trachy-andesitic to andesitic (1300 °C) compositions. Melting of olivine and pyroxene is accompanied by the crystallisation of both phases. The newly-formed olivine has a composition varying from Fo80 to Fo59, becoming progressively enriched in Fe and Ca and depleted in Ni at increasing temperature. The newly-formed pyroxene has a variable Ca content, and is enriched in Al and Cr and depleted in Fe and Mn. The new-grown olivine and pyroxene crystals have a strong affinity with chondritic/primitive achondrites compositions, in contrast to the melts that have a good affinity to a bulk HED composition. Overall, the combination of melting and crystallisation fixes the amount of silicatic liquid to a rather constant value of 10% vol.SR-µCT was used to create 3D reconstructions of the experimental samples, in order to evaluate the efficiency of metal segregation at increasing degrees of partial melting. At increasing temperature, no change in the object density (number of 3D particles divided by the sample volume) is observed but only a progressive increase of the roundness and sphericity of the particles. This suggests that, even in presence of an interconnected liquid silicate phase (~10% vol), the coalescence of the metal phases does not occur spontaneously and other forces such as rotational spin or deformation are needed to segregate metal under these conditions.
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- 2022
8. X‐ray computed tomography: Morphological and porosity characterization of giant Antarctic micrometeorites
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Andrew King, Andrea Longobardo, Luigi Folco, M. D. Suttle, Z. Dionnet, Alessandra Rotundi, and Vincenzo Della Corte
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Geophysics ,Space and Planetary Science ,X ray computed ,Mineralogy ,Tomography ,Porosity ,Geology ,Characterization (materials science) - Published
- 2020
9. Coesite in a Muong Nong‐type tektite from Muong Phin, Laos: Description, formation, and survival
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Matteo Masotta, Billy P. Glass, F. Campanale, Luigi Folco, Glass, B, Folco, L, Masotta, M, and Campanale, F
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Thesaurus (information retrieval) ,Geophysics ,Type (biology) ,Space and Planetary Science ,Tektite ,Muong Nong-type Australasian tektite, coesite-bearing inclusions, coesite formation ,Coesite ,engineering ,Geochemistry ,engineering.material ,Geology - Abstract
We examined 16 white opaque inclusions exposed on two polished slices of a Muong Nong-type Australasian tektite from Muong Phin, Laos. The inclusions usually consist of a core, surrounded by a froth layer, and a quartz neoblast layer. The cores are composed primarily of a mixture of silica glass, coesite, and quartz in varying proportions. A thin (up to ~4 μm) layer of SiO2-poor glass enriched in FeO, MgO, CaO, Al2O3, and TiO2 is observed as a bright halo in backscattered electron images around the quartz neoblasts and in places contains μm-sized crystals, which may be Fe,Mg-rich spinel. The distribution and textural relationships between the coesite-bearing inclusions and the tektite matrix point to an in situ formation of the coesite due to an impact, rather than to infall, from a nearby impact, into tektite melt produced by the aerial burst of a bolide. The quartz neoblasts probably formed by crystallization of silica melt squeezed out of the inclusion core during the development of the froth layer. The bright halo may be the result of silica diffusing from the adjacent tektite melt into the growing quartz neoblasts. We propose that the survival of coesite was possible due to the froth layer that acted as a heat sink during bubble expansion and then as a thermal insulator.
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- 2020
10. Hydrothermal activity on the<scp>CV</scp>parent body: New perspectives from the giant Transantarctic Mountains minimeteorite<scp>TAM</scp>5.29
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M. D. Suttle, Jens Najorka, Luigi Folco, Jacopo Nava, Matteo Massironi, R. Spiess, and Cristian Carli
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MICROMETEORITES ,ORIGIN ,Geochemistry ,CONSTRAINTS ,DIFFRACTION ,CARBONACEOUS CHONDRITES ,AQUEOUS ALTERATION ,BODIES ,MATRIX ,RIMS ,INCLUSIONS ,Parent body ,Hydrothermal circulation ,Geophysics ,Space and Planetary Science ,Geology - Published
- 2019
11. Correction to: Optical tweezers in a dusty universe
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Pietro Giuseppe Gucciardi, Alessandro Magazzù, Onofrio M. Maragò, D. Bronte Ciriza, L. Inno, Alessandra Rotundi, Angela Ciaravella, Ivano Bertini, M. G. Donato, Eleonora Ammannito, Giuseppe Sindoni, Cesare Cecchi-Pestellini, P. Polimeno, Antonino Foti, Rosalba Saija, V. Della Corte, Maria Antonia Iatì, A. Saidi, Luigi Folco, and A. Jimenez Escobar
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Physics ,Optical tweezers ,media_common.quotation_subject ,General Physics and Astronomy ,Astronomy ,Universe ,media_common - Published
- 2021
12. Shock-twinned zircon in ejecta from the 45-m-diameter Kamil crater in southern Egypt
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Aaron J. Cavosie and Luigi Folco
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Impact crater ,Geochemistry ,Ejecta ,Geology ,Shock (mechanics) ,Zircon - Abstract
With an age of less than ~5000 yr and a diameter of 45 m, Kamil crater in Egypt is one of the youngest and smallest terrestrial impact craters known to date. Abundant evidence of shock-deformed sandstone has been reported from Kamil crater, including shatter cones, vesicular impact glass, high-pressure polymorphs of silica and carbon, planar deformation features (PDFs) and planar fractures (PFs) in quartz, dissociated zircon, melt veins, and intergranular melt, giving rise to a range of estimated shock pressures from ~20 to ~60 GPa. Here, we investigated shocked zircon from Kamil crater through characterization of microstructures in a centimeter-sized clast of shocked nonporous sandstone ejecta, previously described as containing quartz grains with PDFs and PFs, coesite, stishovite, diamond, and lechatelierite. Orientation analysis by electron backscatter diffraction (EBSD) showed that the quartz arenite consists of damaged detrital quartz grains surrounded by a matrix of either comminuted quartz or intergranular melt. Individual quartz grains are pervasively fractured (abundant PFs and PDFs); apparent isotropic crushing resulted in uniformly and highly dispersed orientation clusters on pole figures. Zircon grains are not abundant; however, four of 19 grains analyzed by EBSD contained {112} deformation twin lamellae, with individual lamellae ranging in length from 1 to 2 µm. Lengths of twin lamellae in Kamil zircon grains are anomalously short compared to those reported in shocked zircon from other impact structures, where individual lamellae are tens of micrometers long. Previous empirical studies have suggested that {112} twin lamellae in zircon form at ~20 GPa in non-porous target rocks, a finding supported by their coexistence, in some impactites, with high-pressure phases such as reidite. The only available experimental constraint, by diamond anvil cell, found {112} twins in zircon powder quenched at 20 GPa. The presence of coesite, stishovite, lechatelierite, and shocked quartz with PDFs in the studied sample is consistent with empirically derived pressure estimates of ~20 GPa for {112} twin formation in zircon in the ejecta sample from Kamil crater. Kamil thus represents the smallest and youngest impact structure where shock-twinned zircon has been reported. Given the apparent efficiency of {112} twin formation (21% of grains), shock-twinned zircon is here shown to provide a robust and readily identifiable record of shock deformation in a relatively common mineral at one of the smallest known terrestrial impact craters.
- Published
- 2021
13. Supplemental Material: Shock-twinned zircon in ejecta from the 45-m-diameter Kamil crater in southern Egypt
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Luigi Folco and Aaron Cavosie
- Abstract
Table S1: Electron backscatter diffraction (EBSD) analysis conditions
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- 2021
14. The atmospheric entry of fine-grained micrometeorites: The role of volatile gases in heating and fragmentation
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M. van Ginneken, Qingyang Lin, Luigi Folco, M. D. Suttle, Sara S. Russell, Jens Najorka, Matthew J. Genge, and Science and Technology Facilities Council (STFC)
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Geochemistry & Geophysics ,DUST ,010502 geochemistry & geophysics ,01 natural sciences ,Astrobiology ,ACCRETION RATE ,Accretion rate ,Fragmentation (mass spectrometry) ,ANTARCTIC MICROMETEORITES ,TEMPERATURES ,0201 Astronomical and Space Sciences ,0103 physical sciences ,0402 Geochemistry ,GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries) ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,PHYLLOSILICATES ,Science & Technology ,MINERALOGY ,METEORITE ,POROSITY ,QUANTIFICATION ,Geophysics ,0403 Geology ,Meteorite ,Space and Planetary Science ,Atmospheric entry ,COSMIC SPHERULES ,Physical Sciences ,Environmental science - Abstract
The early stages of atmospheric entry are investigated in four large (250–950 μm) unmelted micrometeorites (three fine‐grained and one composite), derived from the Transantarctic Mountain micrometeorite collection. These particles have abundant, interconnected, secondary pore spaces which form branching channels and show evidence of enhanced heating along their channel walls. Additionally, a micrometeorite with a double‐walled igneous rim is described, suggesting that some particles undergo volume expansion during entry. This study provides new textural data which links together entry heating processes known to operate inside micrometeoroids, thereby generating a more comprehensive model of their petrographic evolution. Initially, flash heated micrometeorites develop a melt layer on their exterior; this igneous rim migrates inwards. Meanwhile, the particle core is heated by the decomposition of low‐temperature phases and by volatile gas release. Where the igneous rim acts as a seal, gas pressures rise, resulting in the formation of interconnected voids and higher particle porosities. Eventually, the igneous rim is breached and gas exchange with the atmosphere occurs. This mechanism replaces inefficient conductive rim‐to‐core thermal gradients with more efficient particle‐wide heating, driven by convective gas flow. Interconnected voids also increase the likelihood of particle fragmentation during entry and, may therefore explain the rarity of large fine‐grained micrometeorites among collections.
- Published
- 2018
15. Definition and use of functional analogues in planetary exploration
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Vinciane Debaille, Caroline Smith, Frances Westall, Joseph R. Michalski, Hajime Yano, Michel Viso, Luigi Folco, A. Hutzler, Nicolas Bost, Hilde Schroeven-Deceuninck, Jutta Zipfel, Penelope J. Wozniakiewicz, Sara S. Russell, Katherine H. Joy, Jesús Martínez-Frías, John Bridges, Ludovic Ferrière, Martin Lee, Gerhard Kminek, Michael E. Zolensky, Keyron Hickman-Lewis, Frédéric Foucher, Centre de biophysique moléculaire (CBM), Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Università degli Studi di Bologna, The Natural History Museum [London] (NHM), Lunar and Planetary Institute [Houston] (LPI), NASA, Lyndon B. Johnson Space Center ES3, Houston, Texas 77058, European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), University of Manchester [Manchester], University of Pisa - Università di Pisa, University of Leicester, University of Kent [Canterbury], Instituto de Geociencias [Madrid] (IGEO), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), Université libre de Bruxelles (ULB), Japan Aerospace Exploration Agency [Sagamihara] (JAXA), Naturhistorisches Museum -Wien, University of Glasgow, The University of Hong Kong (HKU), ESA Harwell centre, UK Space Agency, Centre National d’Études Spatiales [Paris] (CNES), Senckenberg – Leibniz Institution for Biodiversity and Earth System Research - Senckenberg Gesellschaft für Naturforschung, and Leibniz Association
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010504 meteorology & atmospheric sciences ,n Mars ,Computer science ,Mars ,01 natural sciences ,Space missions ,Space exploration ,Human–computer interaction ,Planetary exploration ,0103 physical sciences ,Selection (linguistics) ,sort ,010303 astronomy & astrophysics ,Astrophysique ,Analogue ,0105 earth and related environmental sciences ,Astronomy and Astrophysics ,Timeline ,Planetary exploratio ,Astronomie ,Object (computer science) ,Sciences de l'espace ,Space and Planetary Science ,[SDU]Sciences of the Universe [physics] ,Spare part ,Focus (optics) ,Word (computer architecture) - Abstract
The practical limitations inherent to human and robotic planetary exploration necessitate the development of specific protocols and methods. This non-standard approach requires testing and validation phases in order to optimise instrumental setups and improve data interpretation; this can occur prior to, during, or even after a mission. Flight instruments, and/or their spare models, may be evaluated using relevant terrestrial materials and/or locations. These materials are called analogues: “analogue sites” for large-scale locations, and “analogue samples” for smaller-scale materials. Depending on the scientific domain, the word “analogue” may carry different meanings but is invariably used to denote objects having compositions and/or physical properties similar to specific extraterrestrial objects. However, due to the variability in composition and properties of natural materials, there are always – inevitably – some differences between the analogue and the object(s) to which it refers. In analogue studies, it is, thus, important to focus on the specific properties that need to be imitated and to consider analogue properties rather than analogue sites or samples alone. Here, we introduce the concept of “functional analogues”. We first make an overview of the different types of analogues and sort them according to their utility. We then describe how different types of functional analogues can be used throughout the timeline of space missions, from the evaluation of different methods in the definition of a mission to understanding the results acquired by probes exploring extraterrestrial bodies. Finally, logical pathways are outlined that facilitate the selection of the best-suited functional analogue(s) according to their intended use and taking into account practical limitations., SCOPUS: ar.j, info:eu-repo/semantics/published
- Published
- 2021
16. I‐Type Cosmic Spherules as Proxy for the Δ′ 17 O of the Atmosphere—A Calibration With Quaternary Air
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Stefan Weyer, Andreas Pack, Meike B. Fischer, Luigi Folco, Martin Oeser, Stefan T.M. Peters, and Fabian Zahnow
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Atmospheric Science ,COSMIC cancer database ,010504 meteorology & atmospheric sciences ,Calibration (statistics) ,Paleontology ,chemistry.chemical_element ,010502 geochemistry & geophysics ,Oceanography ,Atmospheric sciences ,01 natural sciences ,Oxygen ,Microeteorites ,Atmosphere ,chemistry ,Oxygen isotopes ,Paleo atmosphere ,Microeteorites, Oxygen isotopes, Fractionation, Paleo atmosphere ,Fractionation ,Quaternary ,Proxy (statistics) ,0105 earth and related environmental sciences - Published
- 2021
17. Optical tweezers in a dusty universe: Modeling optical forces for space tweezers applications
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Pietro Giuseppe Gucciardi, Angela Ciaravella, Eleonora Ammannito, P. Polimeno, V. Della Corte, I. Bertini, Onofrio M. Maragò, Alessandro Magazzù, Maria Antonia Iatì, Cesare Cecchi-Pestellini, M. G. Donato, Antonino Foti, Rosalba Saija, Alessandra Rotundi, Giuseppe Sindoni, A. Saidi, Luigi Folco, A. Jimenez Escobar, D. Bronte Ciriza, and L. Inno
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Fluid Flow and Transfer Processes ,Physics ,Range (particle radiation) ,010504 meteorology & atmospheric sciences ,business.industry ,media_common.quotation_subject ,General Physics and Astronomy ,01 natural sciences ,Universe ,Light scattering ,Trap (computing) ,Optics ,Optical tweezers ,Radiation pressure ,0103 physical sciences ,11. Sustainability ,Tweezers ,business ,010303 astronomy & astrophysics ,Nanoscopic scale ,0105 earth and related environmental sciences ,media_common - Abstract
Optical tweezers are powerful tools based on focused laser beams. They are able to trap, manipulate, and investigate a wide range of microscopic and nanoscopic particles in different media, such as liquids, air, and vacuum. Key applications of this contactless technique have been developed in many fields. Despite this progress, optical trapping applications to planetary exploration are still to be developed. Here we describe how optical tweezers can be used to trap and characterize extraterrestrial particulate matter. In particular, we exploit light scattering theory in the T-matrix formalism to calculate radiation pressure and optical trapping properties of a variety of complex particles of astrophysical interest. Our results open perspectives in the investigation of extraterrestrial particles on our planet, in controlled laboratory experiments, aiming for space tweezers applications: optical tweezers used to trap and characterize dust particles in space or on planetary bodies surface.
- Published
- 2021
18. The formation of impact coesite
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Enrico Mugnaioli, Luigi Folco, Mauro Gemmi, F. Campanale, Campanale, F, Mugnaioli, E, Gemmi, M, and Folco, L
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Multidisciplinary ,Materials science ,Tektite ,Science ,shock metamorphism, ctesite, solid state transition ,Nucleation ,engineering.material ,Mineralogy ,Article ,Strewn field ,law.invention ,Impact crater ,law ,Coesite ,Planetary science ,engineering ,Medicine ,Crystallization ,Petrology ,Ejecta ,Quartz - Abstract
Coesite in impact rocks is traditionally considered a retrograde product formed during pressure release by the crystallisation of an amorphous phase (either silica melt or diaplectic glass). Recently, the detailed microscopic and crystallographic study of impact ejecta from Kamil crater and the Australasian tektite strewn field pointed in turn to a different coesite formation pathway, through subsolidus quartz-to-coesite transformation. We report here further evidence documenting the formation of coesite directly from quartz. In Kamil ejecta we found sub-micrometric single-coesite-crystals that represent the first crystallization seeds of coesite. Coesite in Australasian samples show instead well-developed subeuhedral crystals, growing at the expenses of hosting quartz and postdating PDF deformation. Coesite (010) plane is most often parallel to quartz {10–11} plane family, supporting the formation of coesite through a topotactic transformation. Such reaction is facilitated by the presence of pre-existing and shock-induced discontinuities in the target. Shock wave reverberations can provide pressure and time conditions for coesite nucleation and growth. Because discontinuities occur in both porous and non-porous rocks and the coesite formation mechanism appears similar for small and large impacts, we infer that the proposed subsolidus transformation model is valid for all types of quartz-bearing target rocks.
- Published
- 2021
19. Contributors
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Masanao Abe, Jérôme Aléon, Alice Aléon-Toppani, Allan Bennett, Lucy Berthoud, Janet Borg, John C. Bridges, Donald E. Brownlee, Rosario Brunetto, Don Burnett, John Robert Brucato, Vincenzo Della Corte, Vinciane Debaille, Fabrizio Dirri, Zahia Djouadi, Heather L. Enos, Ludovic Ferrière, Luigi Folco, Frédéric Foucher, Ian A. Franchi, Akira Fujiwara, Matthieu Gounelle, Monica M. Grady, John Holt, Aurore Hutzler, Eric A. Jerde, Amy Jurewicz, Junichiro Kawaguchi, Dante S. Lauretta, Stefano Leuko, Andrea Longobardo, Jonathan I. Lunine, Yves Marrocchi, Andrea Meneghin, Ernesto Palomba, Anjani T. Polit, Thomas Pottage, Yuqi Qian, Dan Reisenfeld, Petra Rettberg, Heather L. Roper, Alessandra Rotundi, Sara S. Russell, Scott A. Sandford, Caroline L. Smith, Evgeny Slyuta, Shogo Tachibana, Elizabeth J. Tasker, Akira Tsuchiyama, John Vrublevskis, Qian Wang, Qiong Wang, Frances Westall, Roger C. Wiens, Catherine W.V. Wolner, Long Xiao, Makoto Yoshikawa, Jutta Zipfel, and Michael E. Zolensky
- Published
- 2021
20. Isotope fractionation of Fe by hypervelocity impacts evidenced by Australasian microtektites
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Matthias Van Ginneken, Steven Goderis, Bastien Soens, Joke Belza, Frank Vanhaecke, Philippe Claeys, Stepan M. Chernonozhkin, Natalia Artemieva, Claudia González de Vega, Luigi Folco, Billy P. Glass, Eduardo Bolea Fernandez, and Matthew J. Genge
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Isotope fractionation ,Chemistry ,Environmental chemistry ,Hypervelocity - Published
- 2021
21. The aqueous alteration of GEMS-like amorphous silicate in a chondritic micrometeorite by Antarctic water
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M. D. Suttle, Luigi Folco, Enrico Mugnaioli, Matthew J. Genge, F. Campanale, Ian A. Franchi, Xuchao Zhao, Suttle, M, Folco, L, Genge, M, Franchi, I, Campanale, F, Mugnaioli, E, and Zhao, X
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Antarctica ,Aqueous alteration ,GEMS ,Micrometeorites ,Weathering ,Aqueous solution ,010504 meteorology & atmospheric sciences ,Chemistry ,Geochemistry ,Micrometeorite ,010502 geochemistry & geophysics ,01 natural sciences ,Parent body ,Silicate ,Amorphous solid ,chemistry.chemical_compound ,Geochemistry and Petrology ,Mafic ,0105 earth and related environmental sciences - Abstract
We analysed the heterogenous fine-grained (sub-μm) matrix of a small (58 × 93 μm), unmelted and minimally heated (
- Published
- 2021
22. A roadmap for a European extraterrestrial sample curation facility – the EURO CARES project
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Thomas Pottage, Caroline Smith, Sara S. Russell, Frédéric Foucher, Frances Westall, A. Hutzler, John W. Holt, Allan Bennett, Vinciane Debaille, Petra Rettberg, A. Meneghin, Ernesto Palomba, John Vrublevskis, Monica M. Grady, Jutta Zipfel, Stefano Leuko, Fabrizio Dirri, Andrea Longobardo, Yves Marrocchi, Luigi Folco, M. Gounelle, Jérôme Aléon, Lucy Berthoud, John Robert Brucato, John Bridges, Ludovic Ferrière, Ian A. Franchi, and Alessandra Rotundi
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Engineering ,Spacecraft ,business.industry ,Planetary materials, sample return missions, space exploration ,Principal (computer security) ,Sample (statistics) ,Space (commercial competition) ,sample return missions ,Data science ,Space exploration ,EURO-CARES project ,Extraterrestrial life ,Planetary materials ,Agency (sociology) ,business ,space exploration - Abstract
Sample return missions are among the most exciting space missions, providing both scientifically unique information and an unparalleled mechanism for the inspiring the public. Returned samples allow us to make critical ground truth measurements that can calibrate remote sensing measurements from spacecraft. Some scientific studies can only be done in laboratories rather than remotely or with landed spacecraft. Currently Europe does not have a facility suitable for the curation of returned extra-terrestrial samples. This not only hinders European Space Agency (ESA) missions, but also renders European institutions and Principal Investigators unable to fully participate as equal participants in missions implemented by other countries. The EURO CARES project was the first European attempt to review and evaluate the current state-of-the-art in curatorial practice for sample return missions, and determine the different and necessary steps in order to create a fully functional European Extra-terrestrial Sample Curation Facility to match the ESA requirements.
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- 2021
23. Cosmic dust investigation by optical tweezers for space exploration
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Alessandra Rotundi, Luigi Folco, Alessandro Magazzù, P. Polimeno, Pietro Giuseppe Gucciardi, Onofrio M. Maragò, Maria Antonia Iatì, Anna Musolino, Rosalba Saija, Antonino Foti, Maria Grazia Donato, and David Bronte Ciriza
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Physics ,Astronomy ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Substrate (electronics) ,Space (mathematics) ,Space exploration ,Astrobiology ,symbols.namesake ,Optical tweezers ,Tweezers ,symbols ,Astrophysics::Earth and Planetary Astrophysics ,Raman spectroscopy ,Stratosphere ,Cosmic dust - Abstract
Cosmic dust particles are usually collected in space or in the Earth’s stratosphere and deposited on a substrate to be analysed at large terrestrial facilities. We use Raman tweezers technique for the contacless manypulation of cosmic dust particles, to identify their compositions and to characterize their response to optical forces without any substrate effects, documenting the high potential of this novel technique for space exploration.
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- 2021
24. Assessing the analytical potential of optical tweezers for sample return missions
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Antonino Foti, P. Polimeno, Pietro Giuseppe Gucciardi, Rosalba Saija, David Bronte Ciriza, M. D. Suttle, John Robert Brucato, Onofrio M. Maragò, Anna Musolino, Alessandra Rotundi, Alessandro Magazzù, Maria Grazia Donato, Maria Antonia Iatì, and Luigi Folco
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Optics ,Materials science ,Optical tweezers ,business.industry ,business ,Sample (graphics) - Published
- 2021
25. 3D X-ray tomographic analysis reveals how coesite is preserved in Muong Nong-type tektites
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Stefano Peres, Sounthone Singsoupho, Pierre Rochette, F. Campanale, Matteo Masotta, Nicolas Gueninchault, Luigi Folco, Billy P. Glass, Francesco Radica, Lucia Mancini, Enrique Navarro, University of Pisa - Università di Pisa, XRD2 beamline, Elettra - Sincrotrone Trieste S.C.p.A., Strada Statale 14- km 163,5 in AREA Science Park, 34149 Basovizza, Trieste, Italy, Lund University [Lund], Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), University of Delaware [Newark], Zeiss Research Microscopy Solutions, Università degli Studi Roma Tre = Roma Tre University (ROMA TRE), National University of Laos, Universidad Nacional Autónoma de Managua [Nicaragua], Lund Institute of advanced Neutron and X-ray Science (LINXS), Lund University, Lund, Sweden, Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Università degli Studi Roma Tre, Masotta, M, Peres, S, Folco, L, Mancini, L, Rochette, P, Glass, B, Campanale, F, Gueninchault, N, Radica, F, Singsoupho, S, and Navarro, E
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Materials science ,010504 meteorology & atmospheric sciences ,Nucleation ,Mineralogy ,lcsh:Medicine ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,engineering.material ,010502 geochemistry & geophysics ,01 natural sciences ,Strewn field ,Article ,Coesite ,lcsh:Science ,Quartz ,0105 earth and related environmental sciences ,Multidisciplinary ,Tektite ,Vesicle ,lcsh:R ,Meteoritics ,engineering ,Muong Nong‐type tektites, ctesite survival, x-ray tomography ,lcsh:Q ,Inclusion (mineral) ,Earth (classical element) - Abstract
Muong Nong-type (MN) tektites are a layered type of tektite associated to the Australasian strewn field, the youngest (790 kyr) and largest on Earth. In some MN tektites, coesite is observed in association with relict quartz and silica glass within inclusions surrounded by a froth layer. The formation of coesite-bearing frothy inclusions is here investigated through a 3D textural multiscale analysis of the vesicles contained in a MN tektite sample, combined with compositional and spectroscopic data. The vesicle size distribution testifies to a post-shock decompression that induced melting and extensive vesiculation in the tektite melt. Compared to free vesicles, nucleated homogeneously in the tektite melt, froth vesicles nucleated heterogeneously on relict quartz surfaces at the margins of coesite-bearing inclusions. The rapid detachment of the froth vesicles and prompt reactivation of the nucleation site favoured the packing of vesicles and the formation of the froth structure. Vesicle relaxation time scales suggest that the vesiculation process lasted few seconds. The formation of the froth layer was instrumental for the preservation of coesite, promoting quenching of the inclusion core through the subtraction of heat during froth expansion, thereby physically insulating the inclusion until the final quench of the tektite melt.
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- 2020
26. Skeletal crystallization of quartz from SiO2 impact melt
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Agnese Fazio and Luigi Folco
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Materials science ,Chemical engineering ,law ,Crystallization ,Quartz ,law.invention - Abstract
1. Introduction A recent study on a Muong Nong-type tektite [1] revealed the occurrence of quartz with a “spongy texture”. The orientation and distribution of the voids in quartz were supposed to be crystallographically controlled. Similar structures were not reported before in the literature except for a glass impactite from the 45-m-Kamil crater, Egypt (sample L09) [2]. No Raman or TEM studies were carried out on this lapillus and due to the occurrence of voids, this SiO2-rich material was interpreted as glass. The renewed interest induced us to check again these structures in Kamil impactites. They were found along borders and fractures in numerous quartz relicts occurring in impact melt lapilli. In this work, we present the preliminary results of the characterization of these structures. 2. Impactite L09 The present study focuses on the SiO2 glass-rich impactite L09 (max length ~5 cm). This sample was described in [2] as white glass, i.e., a glass derived from the melting of the target rock without interaction with the projectile (Ni below detection limit). The glass is locally stained by reddish-brownish material. Among Kamil white glasses, L09 is the only sample showing large quartz relicts (up to a few millimeters). 3. Methods The sample was optically characterized through polarized microscope and Raman spectroscopy. Successively, it was investigated by scanning electron microscopy (SEM) and spot chemical analyses from the vesicular glass and quartz relicts were acquired through electron microprobe (EMP). 4. Results Under crossed polarized light the quartz relicts have a very low birefringence and show sporadic birefractive domains. In the birefractive domains, planar deformation features (PDFs) have been observed. Raman spectra of quartz relicts vary between a pure SiO2 glass spectrum with the typical large asymmetric band at ~490 cm-1 and a glass-free shocked-quartz spectrum (main peak at 460 cm-1). Shocked-quartz is easily recognized by Raman spectroscopy: the peaks are shifted towards lower frequencies due to the increase in the angle spanning two tetrahedra [3,4]. Up to two sets of PDFs were recognized at the SEM. PDFs are irregular, closely spaced, enlarged, and tend to coalesce. The PDF areas are in spatial continuity with PDF-free amorphous regions. The PDF-free amorphous regions can contain sporadic vesicles. No flux textures have been recognized in quartz relicts. Occasionally, quartz relicts are crossed by vesicular glass veins chemically enriched in Al2O3 and FeO and open fractures. The margins of the quartz relicts and fractures are mostly surrounded by a layer (usually 30-µm-thick; exceptionally up to 100-µm-thick) of unshocked quartz (Raman main peak at 465 cm-1). Quartz appears in form of skeletal hexagonal aggregates. The numerous voids left out from the skeletal growth are partially filled by iron oxides. The number of the voids increases and their size decreases towards the quartz relicts describing a kind of rim. Small concentric fractures are frequent in the quartz relicts, marking the rim of the skeletal quartz layers. No cristobalite or high-pressure SiO2 polymorphs (i.e., coesite and stishovite) have been detected by Raman. 5. Preliminary discussion The occurrence of skeletal quartz is indicative of a rapid crystallization of the quartz from a fluid phase. Due to the size of the impact event and size of the lapillus, a hydrothermal post-shock alteration could be ruled out. Thus, it is plausible that the quartz crystallized from a SiO2-rich melt. Due to its viscosity, this melt should have been formed at the same location where the skeletal quartz occurs. The melt formed at the expense of the highly-shocked-quartz/diaplectic-glass grains with a minor involvement of the Si-Fe-Al surrounding melt/glass. The melting should have occurred immediately after the pressure release, in the early decompression stage. The subsequent drop of the temperature induced the fast (skeletal) crystallization of the quartz. That probably started in the stability field of β-quartz (4.5 GPa Acknowledgements This work is supported by the Deutsche Forschungsgemeinschaft (DFG; FA 1599/1-1 to AF). Prof. Langenhorst is thanked for the access to the SEM/FIB and TEM facilities at the University of Jena founded via the Gottfried Wilhelm Leibniz prize (LA830/14-1). Dr. Kiefer (University of Jena) is acknowledged for technical assistance during the EMP measurements. The studied sample was collected during the 2010 geophysical expedition carried out within the framework of the 2009 Italian- Egyptian Year of Science and Technology and supported by the Italian Ministero degli Affari Esteri e Cooperazione Internazionale (MAECI)—Progetti di Grande Rilevanza. References [1] Glass, B.P., et al. (2020) Coesite in a Muong Nong-type tektite from Muong Phin, Laos: Description, formation, and survival. Meteoritics & Planetary Science. 55:253–273. [2] Fazio, A., et al. (2016) Target-projectile interaction during impact melting at Kamil Crater, Egypt. Geochimica et Cosmochimica Acta 180:33-50. [3] Fritz, J., et al. (2011) Shock experiments on quartz targets pre-cooled to 77 K. International Journal of Impact Engineering 38:440-445. [4] Mcmillan, P.F., G.H. Wolf, and P. Lambert (1992) A Raman-Spectroscopic study of shocked single crystalline quartz. Physics and Chemistry of Minerals 19:71-79.
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- 2020
27. Partial melting of an enstatite chondrite at 1 GPa: Implications for early planetary differentiation
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Luigi Folco, Luca Ziberna, Matteo Masotta, and Robert Myhill
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Materials science ,Chondrite ,Partial melting ,Enstatite ,engineering ,engineering.material ,Planetary differentiation ,Astrobiology - Abstract
We present new time series partial melting experiments performed on a natural enstatite chondrite (EL6), aimed at investigating the textural and geochemical changes induced by silicate-metal equilibration during early planetary differentiation. The starting material of our experiments consisted of small fragments (ca. 50 mg) obtained from the interior of the enstatite chondrite MCY 14005 (MacKay Glacier, Antarctica), collected during the XXX° Italian Expedition in Antarctica (PNRA). Experiments were performed in graphite capsules at a pressure of 1 GPa, at temperature ranging from 1100 to 1300 °C, with run durations from 1 to 24 h. The initial phase assemblage of the enstatite chondrite, mostly composed by granular enstatite and Fe-Ni metal (up to 400 µm in size) with minor amounts of sulphides and plagioclase, undergoes significant changes with increasing temperature and run duration. At 1100 °C, no silicate melt is produced and subsolidus reactions occur at the contact between the metal and silicate phases. At 1200 °C, small amounts of silicate melt are produced at the grain boundaries and enstatite grains in contact with the melt grow Fe-enriched rims. The metal portions are characterized by two immiscible liquid phases that exhibit rounded shapes when in contact with the silicate melt, whereas smaller (micrometric) liquid metal spheres occur isolated within the silicate melt throughout the experimental charges. These features are already observed in the 1 h experiment but become increasingly evident with increasing run duration, and at higher temperatures. In the experiments performed at 1300 °C, the amount of silicate melt increases and new silicate minerals form (olivine and low-Ca-pyroxene).Enstatite chondrites are characterized by an oxygen isotope composition similar to that of the bulk Earth and Moon, and are considered to have initially formed in the terrestrial planetary zone of the solar nebula. For this reason, they represent a suitable material to investigate the early planetary differentiation processes that occurred in the proto-Earth system. Preliminary results from our experiments indicate that, at the investigated oxygen fugacity (1-2 log units below the IW buffer), the Fe-Si exchange between the metal and silicate phases allows the formation of silicate melt and silicate phases such as olivine and low-Ca-pyroxene. At the same time, the change in shape of the metal grains (increasingly circular/spherical with increasing temperature) and the overall reduction of their number density with increasing experimental time point to rapid aggregation of the metal phase and, possibly, to fast silicate-metal differentiation in small planetesimals.
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- 2020
28. The Extraterrestrial Dust Flux: Size Distribution and Mass Contribution Estimates Inferred From the Transantarctic Mountains (TAM) Micrometeorite Collection
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Luigi Folco and M. D. Suttle
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DEEP-SEA SPHERULES ,COSMIC SPHERULES ,INTERPLANETARY DUST ,INTERNAL STRUCTURE ,FRONTIER MOUNTAIN ,ACCRETION RATE ,ANTARCTIC ICE ,VICTORIA LAND ,EARTH ,INFLUX ,Flux ,Atmospheric sciences ,Geophysics ,Space and Planetary Science ,Geochemistry and Petrology ,Asteroid ,Micrometeorite ,Extraterrestrial life ,Earth and Planetary Sciences (miscellaneous) ,Geology ,Cosmic dust - Published
- 2020
29. Characteristics of the Sahara as a meteorite recovery surface
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Svend Buhl, Hasnaa Chennaoui Aoudjehane, Pierre Rochette, Néjia Laridhi Ouazaa, Jérôme Gattacceca, Luigi Folco, A. J. Timothy Jull, M. Aboulahris, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), University of Arizona, Université de Tunis El Manar (UTM), Museo Nazionale dell'Antartide, Università degli Studi di Siena = University of Siena (UNISI), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Université Tunis El Manar (UTM), Università degli Studi di Siena (UNISI), and Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
FLUX ,BULLETIN ,Geochemistry ,North africa ,Weathering ,010502 geochemistry & geophysics ,01 natural sciences ,CLASSIFICATION ,Chondrite ,SEARCH ,0103 physical sciences ,Brachinite ,010303 astronomy & astrophysics ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,ATACAMA DESERT ,C-14 TERRESTRIAL AGES ,HOT ,OMAN ,COLLECTION AREA ,ORDINARY CHONDRITES ,Geophysics ,Meteorite ,13. Climate action ,Space and Planetary Science ,[SDU.OTHER]Sciences of the Universe [physics]/Other ,Geology ,Systematic search - Abstract
International audience; We describe the geological, geomorphological, and paleoclimatic setting of the Sahara of North Africa in particular, focused on the main meteorite dense collection areas (DCA; Morocco, Algeria, Tunisia, and Libya). We report on the outcome of several meteorite recovery field expeditions in Morocco and Tunisia since 2008, by car and by foot, that applied systematic search methods. The number of meteorites collected is 41 ordinary chondrites and one brachinite. The statistics of unpaired ordinary chondrites indicates that H chondrites are more abundant (21) than L chondrites (12), while LL chondrites are rare (2). Our meteorite density estimates for Tunisia and Morocco are in the order of magnitude of 1 met km(-2). An estimate of the total maximum number of meteorites that could be recovered from the Sahara is 780,000 meteorites. We selected 23 meteorites from Aridal, Bou Kra, Bir Zar, and Tieret DCAs for C-14 dating. The results show a wide range of terrestrial ages from 0.4 to more than 40 kyr with a majority of meteorites showing ages between 0.4 and 20 kyr. The weathering degree of these meteorites is ranges from minor (W1) to strong (W4). The highest weathering grades result from repeated oscillations between high and low humidity in the Sahara. However, there appears to be no correlation between weathering grade and terrestrial age of meteorites.
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- 2019
30. Australasian microtektites: Impactor identification using Cr, Co and Ni ratios
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Billy P. Glass, Massimo D'Orazio, Pierre Rochette, Luigi Folco, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA)
- Subjects
010504 meteorology & atmospheric sciences ,Tektite ,tektites ,tektites, australsian icrotektites, impact craterin, impact melting ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,Mineralogy ,010502 geochemistry & geophysics ,01 natural sciences ,Strewn field ,Plume ,Meteorite ,Impact crater ,13. Climate action ,Geochemistry and Petrology ,Chondrite ,australsian icrotektites ,impact melting ,impact craterin ,Ejecta ,Achondrite ,Geology ,0105 earth and related environmental sciences - Abstract
International audience; Impactor identification is one of the challenges of large-scale impact cratering studies due to the dilution of meteoritic material in impactites (typically
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- 2018
31. Parentage Identification of Differentiated Achondritic Meteorites by Hand-held Energy Dispersive X-Ray Fluorescence Spectrometry
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Tommaso Di Rocco, Massimo D'Orazio, Maurizio Gemelli, and Luigi Folco
- Subjects
Achondrite ,Materials science ,010504 meteorology & atmospheric sciences ,Hand-held XRF ,Hand held ,Analytical chemistry ,Geology ,010502 geochemistry & geophysics ,01 natural sciences ,Achondrite, Hand-held XRF, Meteorite, Planetary basalts ,Meteorite ,Geochemistry and Petrology ,Planetary basalts ,Energy Dispersive X-Ray Fluorescence Spectrometry ,Identification (biology) ,0105 earth and related environmental sciences - Published
- 2017
32. The thermal decomposition of fine-grained micrometeorites, observations from mid-IR spectroscopy
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Matthew J. Genge, M. D. Suttle, Luigi Folco, Sara S. Russell, and Science and Technology Facilities Council (STFC)
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Micrometeorites, IR-spectroscopy, primitive asteroids, comets, Transantarctic Mountain, cosmochemistry ,Transantarctic Mountain ,Population ,Mineralogy ,010502 geochemistry & geophysics ,01 natural sciences ,Cosmochemistry ,IR-spectroscopy ,cosmochemistry ,Geochemistry and Petrology ,0103 physical sciences ,0402 Geochemistry ,comets ,Micrometeorites ,education ,Spectroscopy ,primitive asteroids ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,education.field_of_study ,Chemistry ,Impact gardening ,Thermal decomposition ,Partial melting ,Regolith ,0403 Geology ,Micrometeorite - Abstract
We analysed 44 fine-grained and scoriaceous micrometeorites. A bulk mid-IR spectrum (8–13 μm) for each grain was collected and the entire micrometeorite population classified into 5 spectral groups, based on the positions of their absorption bands. Corresponding carbonaceous Raman spectra, textural observations from SEM-BSE and bulk geochemical data via EMPA were collected to aid in the interpretation of mid-IR spectra. The 5 spectral groups identified correspond to progressive thermal decomposition. Unheated hydrated chondritic matrix, composed predominantly of phyllosilicates, exhibit smooth, asymmetric spectra with a peak at ∼10 μm. Thermal decomposition of sheet silicates evolves through dehydration, dehydroxylation, annealing and finally by the onset of partial melting. Both CI-like and CM-like micrometeorites are shown to pass through the same decomposition stages and produce similar mid-IR spectra. Using known temperature thresholds for each decomposition stage it is possible to assign a peak temperature range to a given micrometeorite. Since the temperature thresholds for decomposition reactions are defined by the phyllosilicate species and the cation composition and that these variables are markedly different between CM and CI classes, atmospheric entry should bias the dust flux to favour the survival of CI-like grains, whilst preferentially melting most CM-like dust. However, this hypothesis is inconsistent with empirical observations and instead requires that the source ratio of CI:CM dust is heavily skewed in favour of CM material. In addition, a small population of anomalous grains are identified whose carbonaceous and petrographic characteristics suggest in-space heating and dehydroxylation have occurred. These grains may therefore represent regolith micrometeorites derived from the surface of C-type asteroids. Since the spectroscopic signatures of dehydroxylates are distinctive, i.e. characterised by a reflectance peak at 9.0–9.5 μm, and since the surfaces of C-type asteroids are expected to be heated via impact gardening, we suggest that future spectroscopic investigations should attempt to identify dehydroxylate signatures in the reflectance spectra of young carbonaceous asteroid families.
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- 2017
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33. Impact Craters and Meteorites: The Egyptian Record
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Ahmed N. El-Barkooky, Wolf Uwe Reimold, and Luigi Folco
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Martian ,Basement (geology) ,Planetary science ,Meteorite ,Impact crater ,Earth science ,Libyan desert glass ,Meteoritics ,Geology ,Natural (archaeology) - Abstract
This chapter provides an account of the present Egyptian impact cratering record as well as an overview of the Egyptian meteorite collection. The 45-m-diameter Kamil crater in the East Uweinat District in southwestern Egypt is so far the only confirmed impact crater in Egypt. Due to its exceptional state of preservation Kamil can be considered a type-structure for small-scale impacts on Earth. Enigmatic types of natural glasses including the Libyan Desert glass found in the Great Sand Sea and the Dakhleh glass found near Dakhla Oasis (note that Dakhla, Dakhleh and Dakhlah are transliterations) may be products of low-altitude airbursts of large and fragile cometary or asteroidal impactors. A number of circular, crater-shaped geological structures superficially resembling impact craters are discussed. To date the Egyptian meteorite collection totals 2 falls, including the ~10 kg Martian meteorite Nakhla that has served as a keystone for the understanding of magmatic differentiation processes on Mars, and 76 finds. With the exception of a minority of incidental findings, most Egyptian meteorite finds (~75%) were recovered over the last ~30 years from three dense meteorite collection areas, namely the El-Shaik Fedl, Great Sand Sea and Marsa Alam fields. The exceptional exposures of the Precambrian basement and Paleozoic to Cenozoic sedimentary covers in Egypt offer a good opportunity for the identification of new impact structures. Likewise, Egypt’s vast rocky desert surfaces are of great potential for the collection of meteorites through systematic searches. These prospects are fundamental ingredients for fostering the ongoing development of meteoritics and planetary science in Egypt as disciplines for future scientific endeavor in Africa.
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- 2019
34. EURO-CARES - A European Sample Curation Facility for Sample Return Missions
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Jérôme Aléon, Ludovic Ferrière, Jutta Zipfel, Matthieu Gounelle, Caroline Smith, Sara S. Russell, Andrea Longobardo, John W. Holt, Frances Westall, John Bridges, Petra Rettberg, John Robert Brucato, Vinciane Debaille, John Vrublevskis, Yves Marrocchi, Stefan Leuko, Luigi Folco, Lucy Berthoud, Frédéric Foucher, Thomas Pottage, Michael Guest, Allan Bennett, A. Hutzler, Ben Dryer, Maurizio Gemelli, A. Meneghin, Alessandra Rotundi, Ian A. Franchi, Ernesto Palomba, and Monica M. Grady
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Scientific instrument ,010504 meteorology & atmospheric sciences ,Planetary protection ,Computer science ,Mars Exploration Program ,Building design ,Sterilization (microbiology) ,01 natural sciences ,Space exploration ,Technologie des autres industries ,Biosafety ,Sample return mission ,0103 physical sciences ,EURO-CARES (European Curation of Astromaterials Returned from the Exploration of Space) ,Systems engineering ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences - Abstract
EURO-CARES (European Curation of Astromaterials Returned from the Exploration of Space) was a three-year multinational project (2015-2017) funded by the European Commission's Horizon 2020 research programme. The objective of EURO-CARES was to create a roadmap for the implementation of a European Extra-terrestrial Sample Curation Facility (ESCF). This facility was intended to be suitable for the curation of samples from return missions from the Moon, asteroids, Mars, and other bodies of the Solar System. The EURO-CARES project covered five technical areas, led by scientists and engineers from institutions across Europe. 1. Planetary Protection: Planetary protection requirements and implementation approaches were assessed by experts and guided by international policy. Existing sterilization methods and techniques were reviewed. It was found that measures already employed for high containment biosafety facilities are suitable for a restricted sample return mission. However, the development of certain technologies, such as a 'double walled' isolator, remote manipulation, integration of scientific analytical instruments, etc. is also required. 2. Facilities and Infrastructure: Aspects from building design to storage of the samples were examined in the project. Requirements for the facility included that it contained a receiving laboratory, a cleaning and opening laboratory, a bio-assessment laboratory, a curation laboratory, and sample storage. Different design solutions were prepared in collaboration with architects. 3. Instruments and Methods: The methodology of characterisation of returned samples and the instrument base required at the ESCF were determined. The analyses provide an appropriate level of characterisation while ensuring minimal contamination and minimal alteration of the sample. When the samples are returned to Earth, several stages of studies would be conducted. 4. Analogue Samples: Analogue proxy samples were considered critical for testing sample handling, preparation techniques, storage conditions, planetary protection measures, as well as to validate new analytical methods. A list of useful analogue samples has been assembled. 5. Sample Transport: The Earth re-entry capsule from a sample return mission is targeted at a specific landing ellipse on Earth and must then be transported safely to the ESCF in an appropriate transport container. Lessons learned from past sample return missions show that preparations for recovery included: training of the recovery team for every possible scenario, possible temporary facilities nearby the landing site, environmental measurements and collection of samples at the landing site, added to this if necessary, would be planetary protection measures. In conclusion, long-term curation of extra-terrestrial samples requires that the samples are kept clean to minimize the risk of Earth contaminants, at the same time as contained, in case of a restricted sample return. This work describes a roadmap for a combined high containment and ultraclean European sample curation facility and the development of the necessary novel scientific and engineering methods and techniques., SCOPUS: cp.p, info:eu-repo/semantics/published
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- 2019
35. A microchondrule-bearing micrometeorite and comparison with microchondrules in CM chondrites
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T. Goral, Sara S. Russell, Martin Lee, Tobias Salge, Matthew J. Genge, Paula Lindgren, M. D. Suttle, Luigi Folco, and Science and Technology Facilities Council (STFC)
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Geochemistry & Geophysics ,Geophysics ,Bearing (mechanical) ,0403 Geology ,Space and Planetary Science ,Chondrite ,law ,Micrometeorite ,0201 Astronomical and Space Sciences ,0402 Geochemistry ,Geology ,law.invention ,Astrobiology - Abstract
We report the discovery of a partially altered microchondrule within a fine-grained micrometeorite.This object is circular
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- 2019
36. Evidence for subsolidus quartz-coesite transformation in impact ejecta from the Australasian tektite strewn field
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Mauro Gemmi, Luke Daly, Luigi Folco, Billy P. Glass, Martin Lee, Enrico Mugnaioli, F. Campanale, Campanale, F, Mugnaioli, E, Folco, L, Gemmi, M, Lee, M, Daly, L, and Glass, B
- Subjects
Materials science ,010504 meteorology & atmospheric sciences ,Tektite ,Shock metamorphism ,Impact ejecta ,Martensitic mechanism ,Mineralogy ,engineering.material ,010502 geochemistry & geophysics ,Subsolidus quartz-to-coesite transformation ,01 natural sciences ,Strewn field ,Australasian tektite strewn field ,Impact crater ,Geochemistry and Petrology ,Planar deformation features ,Coesite ,engineering ,Crystal twinning ,Quartz ,0105 earth and related environmental sciences - Abstract
Coesite, a high-pressure silica polymorph, is a diagnostic indicator of impact cratering in quartz-bearing target rocks. The formation mechanism of coesite during hypervelocity impacts has been debated since its discovery in impact rocks in the 1960s. Electron diffraction analysis coupled with scanning electron microscopy and Raman spectroscopy of shocked silica grains from the Australasian tektite/microtektite strewn field reveals fine-grained intergrowths of coesite plus quartz bearing planar deformation features (PDFs). Quartz and euhedral microcrystalline coesite are in direct contact, showing a recurrent pseudo iso-orientation, with the [1 1 ¯ 1] * vector of quartz near parallel to the [0 1 0]* vector of coesite. Moreover, discontinuous planar features in coesite domains are in textural continuity with PDFs in adjacent quartz relicts. These observations indicate that quartz transforms to coesite after PDF formation and through a solid-state martensitic-like process involving a relative structural shift of { 1 ¯ 0 1 1 } quartz planes, which would eventually turn into coesite (0 1 0) planes. This process further explains the structural relation observed between the characteristic (0 1 0) twinning and disorder of impact-formed coesite, and the 1 0 1 ¯ 1 PDF family in quartz. If this mechanism is the main way in which coesite forms in impacts, a re-evaluation of peak shock pressure estimates in quartz-bearing target rocks is required because coesite has been previously considered to form by rapid crystallization from silica melt or diaplectic glass during shock unloading at 30–60 GPa.
- Published
- 2019
37. A unique CO-like micrometeorite hosting an exotic Al-Cu-Fe-bearing assemblage – close affinities with the Khatyrka meteorite
- Author
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K. Twegar, Jacopo Nava, M. D. Suttle, John Spratt, Luigi Folco, R. Spiess, F. Campanale, Suttle, M, Twegar, K, Nava, J, Spiess, R, Spratt, J, Campanale, F, and Folco, L
- Subjects
0301 basic medicine ,Materials science ,micrometeorites, quasicrystals ,Alloy ,Intermetallic ,lcsh:Medicine ,engineering.material ,Article ,03 medical and health sciences ,Khatyrkite ,0302 clinical medicine ,Chondrite ,Early solar system ,lcsh:Science ,Petrology ,Multidisciplinary ,Olivine ,lcsh:R ,Mineralogy ,Crystallography ,Geochemistry ,030104 developmental biology ,Meteorite ,Micrometeorite ,Carbonaceous chondrite ,engineering ,lcsh:Q ,030217 neurology & neurosurgery - Abstract
We report the discovery of a unique micrometeorite, containing an exotic Al-Cu-Fe alloy composed of two intermixed phases: khatyrkite (CuAl2) and stolperite (CuAl) and both containing minor Fe (2O3: 0.01–0.56 wt%, MnO: 0.03–0.32 wt% and CaO: 0.09–0.22 wt%) and a cumulate layered texture. These properties suggest the micrometeorite is derived from a carbonaceous chondrite (best matched to a CO chondrite) and entered the atmosphere a high speed (~16 kms−1), implying an origin from a highly eccentric orbit. This particle represents the second independent discovery of naturally occurring intermetallic Al-Cu-Fe alloys and is thus similar to the previously reported Khatyrka meteorite - a CV chondrite containing near-identical alloys and the only known natural quasicrystals. We did not observe quasicrystalline phases in this micrometeorite, likely due to the low amounts of Fe in the alloy, insufficient to stabilize quasicrystals. Our discovery confirms the existence of Al-Cu-Fe intermetallic alloys on chondritic parent bodies. These unusual phases require a currently unexplained formation process, we tentatively suggest this could represent the delivery of exotic interstellar material to the inner solar system via impact.
- Published
- 2019
38. Intense aqueous alteration on C-type asteroids: Perspectives from giant fine-grained micrometeorites
- Author
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Sara S. Russell, M. D. Suttle, M. van Ginneken, Luigi Folco, Jens Najorka, and Matthew J. Genge
- Subjects
Aqueous solution ,010504 meteorology & atmospheric sciences ,Geochemistry and Petrology ,Asteroid ,Chemistry ,Micrometeorite ,Chondrite ,010502 geochemistry & geophysics ,01 natural sciences ,0105 earth and related environmental sciences ,Astrobiology ,Matrix (geology) ,Cosmic dust - Abstract
This study explores the petrology of five giant (>400 μm) hydrated fine-grained micrometeorites from the Transantarctic Mountain (TAM) micrometeorite collection. For the first time, the extent and mechanisms of aqueous alteration in unmelted cosmic dust are evaluated and quantified. We use a range of criteria, previously defined for use on hydrated chondrites, including phyllosilicate fraction, matrix geochemistry and micro textures. Collectively, these micrometeorites represent ∼2.22 mm2 of intensely altered hydrated chondritic matrix (with petrologic subtypes of
- Published
- 2019
39. 10Be in Australasian microtektites compared to tektites: Size and geographic controls
- Author
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Luigi Folco, Karim Keddadouche, Régis Braucher, Georges Aumaître, Pierre Rochette, C. S. Horng, D.L. Bourles, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Programma Nazionale di Ricerche in Antartide grant [PNRA16_0029], Taiwan Ocean Research Institute [MD97-2142], INSU/CNRS, Agence Nationale de la Recherche through 'Projets thematiques d'excellence' program for the 'Equipements d'excellence' ASTER-CEREGE action, Institut de recherche pour le developpement, A*MIDEX fundation 'Pepiniere d'excellence' program, Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA)
- Subjects
[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,South china ,010504 meteorology & atmospheric sciences ,Target surface ,[SDE.MCG]Environmental Sciences/Global Changes ,Fragmentation (computing) ,Geochemistry ,Sediment ,Geology ,010502 geochemistry & geophysics ,01 natural sciences ,Ejection velocity ,13. Climate action ,Source material ,[SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology ,Ejecta ,[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment ,Scavenging ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences - Abstract
International audience; High Be-10 contents in tektites reported in literature are taken as evidence of a source material, melted at the impact site, enriched in atmospheric Be-10; i.e., a soil or sediment. In 0.8 Ma Australasian tektites, Be-10 content increases with distance from the putative impact location in Indochina, with geographic averages from 69 x 10(6) atoms/g (Indochina) to 136 x 10(6) atoms/g (Australia). Here we report, for the first time, Be-10 contents in microtektites collected from Antarctica and the South China Sea. We show that microtektites are similar to 30 x 10(6) atoms/g richer in Be-10 than tektites from the same geographic areas. Antarctic microtektites, with an average Be-10 content of 184 x 10(6) atoms/g after correction for in situ production, are the richest impact glass ever measured. The simplest explanation for such systematic size and geographic trends is that the source depth of the melt within the target surface decreases with ejection velocity. Indeed, higher initial kinetic energy implies higher launch distances and higher fragmentation of the ejecta. Antarctic microtektite source depth may tentatively be restricted to the upper tens of centimeters at the impact site. Alternative models invoking a marine or loessic sediment source, or a secondary enrichment in the microtektite (either by atmospheric scavenging, selective fractionation by volatilization, or post-depositional contamination) fail to reproduce the observed relationships.
- Published
- 2019
40. Noble gases in micrometeorites from the Transantarctic Mountains
- Author
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Carole Cordier, Pierre Rochette, Mario Trieloff, Luigi Folco, B. Baecker, Matthias Van Ginneken, Ulrich Ott, Max-Planck-Institut für Biophysikalische Chemie - Max Planck Institute for Biophysical Chemistry [Göttingen], Max-Planck-Gesellschaft, Université Grenoble Alpes - Faculté d'Économie de Grenoble (UGA UFR FEG), Université Grenoble Alpes (UGA), Dipartimento di Scienze della Terra [Pisa], University of Pisa - Università di Pisa, Institut für Geowissenschaften [Heidelberg], Universität Heidelberg [Heidelberg], Laboratoire Géochimie, Traçage Isotopique, Minéral et élémentaire - G-Time (Bruxelles, Belgium), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Max Planck Institute for Chemistry (MPIC), Heidelberg University, MTA Atomki, Partenaires INRAE, Université Grenoble Alpes (COMUE) (UGA), University of Pisa, Université libre de Bruxelles (ULB), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA)
- Subjects
Solar System ,010504 meteorology & atmospheric sciences ,[SDV]Life Sciences [q-bio] ,Solar wind ,Comet ,chemistry.chemical_element ,010502 geochemistry & geophysics ,01 natural sciences ,Astrobiology ,Neon ,Interplanetary dust cloud ,[SDU.STU.PL]Sciences of the Universe [physics]/Earth Sciences/Planetology ,Geochemistry and Petrology ,Transantarctic Mountains ,Micrometeorites ,0105 earth and related environmental sciences ,Physics ,Pre-irradiation ,Krypton ,Noble gas ,Noble gases ,chemistry ,Meteorite ,13. Climate action ,[SDU]Sciences of the Universe [physics] ,Cosmic ray exposure ,Terrestrial planet ,Planetary noble gases - Abstract
International audience; The bulk of extraterrestrial matter currently accreted by the Earth is in the form of micrometeorites (MMs) and interplanetary dust particles (IDPs), thus they may have collectively made a substantial contribution to the volatile inventory of the Earth and the other terrestrial planets. We have performed a complete noble gas study, accompanied by a complete petrographic characterization, of MMs from the Transantarctic Mountain (TAM) collection in the size range similar to 300 to similar to 1000 mu m that fell over an extended time period during the last similar to 1 Ma. Our noble gas study includes krypton and xenon, which have been largely missing in previous work. Helium and neon are dominated by a solar component, with generally lower abundance in scoriaceous MMs than in unmelted ones, and also generally lower in abundance than in previously studied MMs, which may be explained by the larger particle size (surface/volume ratio) of the MMs we studied. Considering an enhanced MM flux in the early Solar System, such MMs may have supplied a significant fraction of Earth's neon. A number of MMs have kept what was probably their pre-terrestrial He/Ne ratio, from which we infer that the observed solar component is retained in a tiny surface region not affected by atmospheric entry. The abundances of (volume-correlated) heavier gases are similar to what was found in previous studies of smaller MMs. While Ar contains both solar and "planetary" contributions, the heavy noble gases (Kr, Xe) generally show "planetary" patterns but are often also compromised by terrestrial contamination as evidenced by an enhanced Kr/Xe ratio. Kr and Xe in a subset of scoriaceous MMs are dominated by isotopically fractionated air, possibly acquired during the passage through Earth's ionosphere. Those not obviously affected by air show isotopic ratios similar to primitive meteorites (the Q component), thus primordial heavy gases supplied to the Earth by MMs are likely as those found in macroscopic meteorites. There is no evidence for the presence of a "cometary" Xe component as identified in the coma of comet 67P/Churyumov-Gerasimenko, hence a cometary source for a significant fraction of MMs in the studied size range is unlikely. Cosmogenic helium, neon and argon were detected in several cases. Cosmic ray exposure ages were calculated based on cosmogenic Ne-21 in combination with the Poynting-Robertson effect, but depend on assumptions about atmospheric entry loss. Still, several cases are consistent with an origin from the asteroid belt (even assuming no loss) and one scoriaceous MM (#45b.17) would have to originate from beyond Jupiter. In at least two cases, including #45b.17, the isotopic composition of cosmogenic Ne appears to be inconsistent with predominant production in small particles free-floating in space, however; much of the irradiation of these MMs may have occurred when they were part of larger parent bodies.
- Published
- 2018
41. Flying too close to the Sun – The viability of perihelion-induced aqueous alteration on periodic comets
- Author
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Luigi Folco, Matthew J. Genge, M. D. Suttle, and Sara S. Russell
- Subjects
Solar System ,Materials science ,010504 meteorology & atmospheric sciences ,01 natural sciences ,Astrobiology ,chemistry.chemical_compound ,Comet Halley ,Chondrite ,0103 physical sciences ,Comets ,Solar radiation ,010303 astronomy & astrophysics ,Amphibole ,0105 earth and related environmental sciences ,Magnetite ,Cosmic dust ,Radiogenic nuclide ,nucleus ,Astronomy and Astrophysics ,Comet Tempel-1 ,Comets, dust ,Comets, nucleus ,chemistry ,Space and Planetary Science ,Asteroid ,Sublimation (phase transition) ,dust - Abstract
Comets are typically considered to be pristine remnants of the early solar system. However, by definition they evolve significantly over their lifetimes through evaporation, sublimation, degassing and dust release. This occurs once they enter the inner solar system and are heated by the Sun. Some comets (e.g. 1P/Halley, 9P/Tempel and Hale-Bopp) as well as chondritic porous cosmic dust – released from comets – show evidence of minor aqueous alteration resulting in the formation of phyllosilicates, carbonates or other secondary phases (e.g. Cu-sulphides, amphibole and magnetite). These observations suggest that (at least some) comets experienced limited interaction with liquid water under conditions distinct from the alteration histories of hydrated chondritic asteroids (e.g. the CM and CR chondrites). This synthesis paper explores the viability of perihelion-induced heating as a mechanism for the generation of highly localised subsurface liquid water and thus mild aqueous alteration in periodic comets. We draw constraints from experimental laboratory studies, numerical modelling, spacecraft observations and microanalysis studies of cometary micrometeorites. Both temperature and pressure conditions necessary for the generation and short-term (hour-long) survival of liquid water are plausible within the immediate subsurface ( Most periodic comets which currently pass close to the Sun are dormant, having experienced surface heating, significant cometary activity and dust release in the past. These bodies may be responsible for the partially hydrated cometary micrometeorites we find at the Earth's surface and their aqueous alteration histories may have been produced by perihelion-induced subsurface heating. This is in contrast to radiogenic and impact heating that operated during the early solar system on asteroids. This study has implications for the alteration history of the active asteroid Phaethon, the target of JAXA's DESTINY+ mission.
- Published
- 2020
42. Cosmic Dust: Finding a Needle in a Haystack
- Author
-
Susan Taylor, Luigi Folco, and Scott Messenger
- Subjects
Solar System ,010504 meteorology & atmospheric sciences ,MICROMETEORITES, COSMIC DUST, PLANETARY SCIENCE ,Astrophysics::Cosmology and Extragalactic Astrophysics ,010502 geochemistry & geophysics ,COSMIC DUST ,01 natural sciences ,Astrobiology ,Interplanetary dust cloud ,Geochemistry and Petrology ,Earth and Planetary Sciences (miscellaneous) ,Astrophysics::Solar and Stellar Astrophysics ,Stratosphere ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Cosmic dust ,MICROMETEORITES ,Physics ,COSMIC cancer database ,Astronomy ,Meteorite ,PLANETARY SCIENCE ,Physics::Space Physics ,Particle ,Astrophysics::Earth and Planetary Astrophysics ,Haystack - Abstract
Collecting cosmic dust is a tricky business! Despite Earth's surface being showered by thousands of tons of comic dust every year, such dust is quickly lost in a sea of terrestrial particles. Finding the tiny cosmic treasures requires collecting dust from the cleanest environments where the terrestrial particle background is low. The stratosphere can be sampled via high-flying aircraft, whereas sampling cosmic dust from polar regions and the deep sea requires techniques that concentrate the particles. Collection efforts are worth it. Cosmic dust derives from every dust-producing object in the Solar System, including ancient Solar System materials, possibly even interstellar materials, of a type not found in meteorites.
- Published
- 2016
43. Isotopic and textural analysis of giant unmelted micrometeorites – identification of new material from intensely altered 16O-poor water-rich asteroids
- Author
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J. M. Gibson, Ian A. Franchi, Andrew King, Richard C. Greenwood, Sara S. Russell, Alessandra Rotundi, M. D. Suttle, Luigi Folco, and Z. Dionnet
- Subjects
010504 meteorology & atmospheric sciences ,Population ,010502 geochemistry & geophysics ,01 natural sciences ,Parent body ,Astrobiology ,O-isotopes ,carbonaceous chondrites ,micrometeorites ,water-to-rock ratio ,Geochemistry and Petrology ,Chondrite ,Earth and Planetary Sciences (miscellaneous) ,education ,0105 earth and related environmental sciences ,Ordinary chondrite ,education.field_of_study ,Chondrule ,Geophysics ,Meteorite ,13. Climate action ,Space and Planetary Science ,Micrometeorite ,Carbonaceous chondrite ,Geology - Abstract
Bulk oxygen isotope data has the potential to match extraterrestrial samples to parent body sources based on distinctive δ18O and Δ17O ratios. We analysed 10 giant (>500µm) micrometeorites using combined µCT and O-isotope analysis to pair internal textures to inferred parent body groups. We identify three ordinary chondrite particles (L and LL groups), four from CR chondrites and the first micrometeorite from the enstatite chondrite (EH4) group. In addition, two micrometeorites are from hydrated carbonaceous chondrite parent bodies with 16O-poor isotopic compositions above the terrestrial fractionation line. They experienced intense aqueous alteration, contain pseudomorphic chondrules and are petrographically similar to the CM1/CR1 chondrites. These micrometeorites may be members of the newly established CY chondrites and/or derived from the enigmatic “Group 4” micrometeorite population, previously identified by Yada et al., 2005 [GCA, 69:5789-5804], Suavet et al., 2010 [EPSL, 293:313-320] (and others). One of our 16O-poor micrometeorite plots on the same isotopic trendline as the CO, CM and CY chondrites – “the CM mixing line” (with a slope of ~0.7 and a δ17O intercept of -4.23‰), implies a close relationship and potentially a genetic link to these hydrated chondrites. If position along the CM mixing line reflects the amount of 16O-poor (heavy) water-ice accreted onto the parent body at formation, then the CY chondrites and these 16O-poor micrometeorites must have accreted at least as much water-ice as CM chondrites but potentially more. In addition, thermal metamorphism could have played a role in further raising the bulk O-isotope compositions through the preferential loss of isotopically light water during phyllosilicate dehydration. The study of micrometeorites provides insights into asteroid belt diversity through the discovery of material not currently sampled by larger meteorites, perhaps as a result of atmospheric entry biases preventing the survival of large blocks of friable hydrated material.
- Published
- 2020
44. Silicate liquid immiscibility in impact melts
- Author
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Agnese Fazio, M. Ebert, Alexander Deutsch, Christopher Hamann, Wolf Uwe Reimold, Richard Wirth, Lutz Hecht, and Luigi Folco
- Subjects
Materials science ,010504 meteorology & atmospheric sciences ,010502 geochemistry & geophysics ,01 natural sciences ,Silicate ,meteorites ,chemistry.chemical_compound ,Geophysics ,chemistry ,Chemical engineering ,Space and Planetary Science ,impact cratering ,impact cratering, impact melting, meteorites ,impact melting ,0105 earth and related environmental sciences - Published
- 2018
45. Direct quartz-coesite transformation in shocked porous sandstone from Kamil Crater (Egypt)
- Author
-
Maurizio Gemelli, Matteo Masotta, Enrico Mugnaioli, Luigi Folco, F. Campanale, Folco, L, Mugnaioli, E, Gemelli, M, Masotta, M, and Campanale, F
- Subjects
Kamil crater, shock metamorphism, coesite, direct transition ,010504 meteorology & atmospheric sciences ,Geochemistry ,Geology ,engineering.material ,010502 geochemistry & geophysics ,01 natural sciences ,Transformation (function) ,Impact crater ,Coesite ,engineering ,Porosity ,Quartz ,0105 earth and related environmental sciences - Abstract
Coesite, a high-pressure silica polymorph (pressure 3-10 GPa, temperature < 3000 K), is a diagnostic feature of shock metamorphism associated with impact cratering on quartz-bearing target rocks. It is preserved as a metastable phase in sedimentary target rocks that experienced peak pressures in excess of ~10 GPa, where it typically occurs as intergranular polycrystalline aggregates of microcrystals embedded in silica glass known as "symplectic regions." The presence of coesite in the symplectic regions of rocks experiencing shock conditions beyond the limits of the coesite stability field is a controversial issue. Through a combined scanning and transmission electron microscopy and Raman spectroscopy study of shocked quartzarenites from the 45-m-diameter Kamil Crater (southwest Egypt), we show that coesite in symplectic regions forms through direct subsolidus transformation from quartz, in contrast with the prevailing hypothesis for crystalline targets. The quartz-to-coesite transformation takes place during localized shock-wave reverberation at the beginning of the pore collapse process. Complete pore collapse generates the high temperature regimes responsible for the subsequent production of the embedding silica melts, in part at the expense of the previously formed coesite. This work documents the role of pore collapse in producing localized pressure-temperature-time gradients in shocked porous targets, as predicted by numerical models in the literature.
- Published
- 2018
46. A new type of oxidized and pre-irradiated micrometeorite
- Author
-
Carole Cordier, Luigi Folco, Mario Trieloff, Ulrich Ott, and B. Baecker
- Subjects
Olivine ,Materials science ,micrometeorites, solar system ,Partial melting ,Analytical chemistry ,micrometeorites ,Pyroxene ,engineering.material ,solar system ,010502 geochemistry & geophysics ,01 natural sciences ,chemistry.chemical_compound ,Augite ,chemistry ,Geochemistry and Petrology ,Chondrite ,Micrometeorite ,0103 physical sciences ,engineering ,Plagioclase ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,Magnetite - Abstract
This paper investigates the mineralogy and noble gas composition of a unique micrometeorite from the Transantarctic Mountains, #45c.29. The magnetite rim and the particle interior with olivine, pyroxene and magnetite relict grains (30–250 µm in size) set in a vesicular mesostasis are typical features of coarse-grained, partially melted micrometeorites. Particle #45c.29 stands out from other micrometeorites of this type by the texture of the mesostasis made of abundant plagioclase and augite laths, the remarkably high Ni contents in magnetite and olivine relict grains, and by the similarly high abundance of cosmogenic noble gases ( 21 Ne cos up to 1.62 × 10 −7 cm 3 STP/g and 38 Ar up to 7.2 × 10 −8 cm 3 STP/g). The high Ni content of Fa 26 olivine relict grains (NiO ∼ 0.65 wt%), the high Ni (NiO ∼ 0.8 wt%) and Ti (TiO 2 ∼ 0.3 wt%) contents of magnetite relicts, and the oxygen isotope composition of a sample of the particle (δ 18 O ∼ 2.3‰, δ 17 O ∼ −1.5‰), suggest a parentage with rare equilibrated CK chondrites. Pyroxene and plagioclase are not expected to crystallize during atmospheric entry of micrometeoroids. Their occurrence in #45c.29 may be explained by the Ca-, Al- and Na- rich composition of its precursor – in agreement with the high abundance of plagioclase reported in the matrix of CK chondrites – if combined with a relatively low cooling rate and, therefore, unusual atmospheric entry parameters (velocity/angle) of the micrometeoroid. Given these specific entry parameters, the particle has recorded unique information on mineralogical and textural transformations of micrometeoroids during atmospheric entry, with solid-state oxidation of the olivine relict grains in the igneous rim, and partial melting of relict mineral phases and relict/melt reactions in the particle interior. The cosmogenic 21 Ne/ 22 Ne ratio of 0.94 ± 0.02 is incompatible with major production by cosmogenic ray irradiation of a small particle in space. We propose that micrometeorite #45c.29 mostly records an earlier irradiation stage, in a meteoroid or more likely near the surface (
- Published
- 2018
47. Shock metamorphism and impact melting in small impact craters on Earth: Evidence from Kamil crater, Egypt
- Author
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Carole Cordier, Agnese Fazio, Massimo D'Orazio, Maria Luce Frezzotti, Luigi Folco, Fazio, A, Folco, L, D'Orazio, M, Frezzotti, M, and Cordier, C
- Subjects
Geochemistry ,engineering.material ,Shock (mechanics) ,Shock metamorphism ,Geophysics ,Impact crater ,Space and Planetary Science ,Planar deformation features ,Coesite ,Hypervelocity ,engineering ,Ejecta ,Geophysic ,Geology ,Stishovite - Abstract
Kamil is a 45 m diameter impact crater identified in 2008 in southern Egypt. It was generated by the hypervelocity impact of the Gebel Kamil iron meteorite on a sedimentary target, namely layered sandstones with subhorizontal bedding. We have carried out a petrographic study of samples from the crater wall and ejecta deposits collected during our first geophysical campaign (February 2010) in order to investigate shock effects recorded in these rocks. Ejecta samples reveal a wide range of shock features common in quartz-rich target rocks. They have been divided into two categories, as a function of their abundance at thin section scale: (1) pervasive shock features (the most abundant), including fracturing, planar deformation features, and impact melt lapilli and bombs, and (2) localized shock features (the least abundant) including high-pressure phases and localized impact melting in the form of intergranular melt, melt veins, and melt films in shatter cones. In particular, Kamil crater is the smallest impact crater where shatter cones, coesite, stishovite, diamond, and melt veins have been reported. Based on experimental calibrations reported in the literature, pervasive shock features suggest that the maximum shock pressure was between 30 and 60 GPa. Using the planar impact approximation, we calculate a vertical component of the impact velocity of at least 3.5 km s � 1 . The wide range of shock features and their freshness make Kamil a natural laboratory for studying impact cratering and shock deformation processes in small impact structures.
- Published
- 2014
48. Africa Initiative for Planetary and Space Sciences
- Author
-
Luigi Folco, H. Chennaoui-Aoudjehane, Christian Koeberl, Moulley Charaf Chabou, Elyvin Nkhonjera, Kelali Tekle, Maram Kaire, D. Belhai, David Baratoux, N. C. Mukosi, Pierre Rochette, Meriem Elyajouri, John Bosco Habarulema, Mark Jessell, Zouhair Benkhaldoun, Wolf Uwe Reimold, Katrien Kolenberg, Gayane Faye, Amanda Sickafoose, M. S. Sapah, Mamdouh M. Abdeen, Aberra Mogessie, Roger L. Gibson, A. Lamali, Jesús Martínez-Frías, Axel Hofmann, and Angelo Pio Rossi
- Subjects
Geography ,0103 physical sciences ,Regional science ,General Earth and Planetary Sciences ,Physical geography ,Space Science ,010502 geochemistry & geophysics ,010303 astronomy & astrophysics ,01 natural sciences ,0105 earth and related environmental sciences - Abstract
Elevating planetary and space sciences across Africa could help nations reach their development goals. Efforts will require collaboration, creativity, efficient planning, and political will.
- Published
- 2017
49. Electron crystallography of planetary materials: impactites and micrometeorites
- Author
-
Luigi Folco, Mauro Gemmi, M. D. Suttle, Enrico Mugnaioli, and F. Campanale
- Subjects
Inorganic Chemistry ,Crystallography ,Materials science ,Structural Biology ,Electron crystallography ,General Materials Science ,Physical and Theoretical Chemistry ,Condensed Matter Physics ,Biochemistry - Published
- 2019
50. The extremely reduced silicate-bearing iron meteorite Northwest Africa 6583: Implications on the variety of the impact melt rocks of the IAB-complex parent body
- Author
-
Luigi Folco, Agnese Fazio, Massimo D'Orazio, Jérôme Gattacceca, and Corinne Sonzogni
- Subjects
chemistry.chemical_compound ,Geophysics ,chemistry ,Meteorite ,Space and Planetary Science ,Asteroid ,Geochemistry ,Regolith ,Iron meteorite ,Isotopes of oxygen ,Geology ,Silicate ,Parent body - Abstract
Northwest Africa (NWA) 6583 is a silicate-bearing iron meteorite with Ni = 18 wt%. The oxygen isotope composition of the silicates (∆′17O = −0.439 ‰) indicates a genetic link with the IAB-complex. Other chemical, mineralogical, and textural features of NWA 6583 are consistent with classification as a new member of the IAB-complex. However, some unique features, e.g., the low Au content (1.13 μg g−1) and the extremely reducing conditions of formation (approximately −3.5 ∆IW), distinguish NWA 6583 from the known IAB-complex irons and extend the properties of this group of meteorites. The chemical and textural features of NWA 6583 can be ascribed to a genesis by impact melting on a parent body of chondritic composition. This model is also consistent with one of the most recent models for the genesis of the IAB-complex. Northwest Africa 6583 provides a further example of the wide lithological and mineralogical variety that impact melting could produce on the surface of a single asteroid, especially if characterized by an important compositional heterogeneity in space and time like a regolith.
- Published
- 2013
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