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Bekaert DV, Barry PH, Broadley MW, Byrne DJ, Marty B, Ramírez CJ, de Moor JM, Rodriguez A, Hudak MR, Subhas AV, Halldórsson SA, Stefánsson A, Caracausi A, Lloyd KG, Giovannelli D, Seltzer AM. Ultrahigh-precision noble gas isotope analyses reveal pervasive subsurface fractionation in hydrothermal systems. SCIENCE ADVANCES 2023; 9:eadg2566. [PMID: 37058557 PMCID: PMC10104464 DOI: 10.1126/sciadv.adg2566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 03/16/2023] [Indexed: 06/19/2023]
Abstract
Mantle-derived noble gases in volcanic gases are powerful tracers of terrestrial volatile evolution, as they contain mixtures of both primordial (from Earth's accretion) and secondary (e.g., radiogenic) isotope signals that characterize the composition of deep Earth. However, volcanic gases emitted through subaerial hydrothermal systems also contain contributions from shallow reservoirs (groundwater, crust, atmosphere). Deconvolving deep and shallow source signals is critical for robust interpretations of mantle-derived signals. Here, we use a novel dynamic mass spectrometry technique to measure argon, krypton, and xenon isotopes in volcanic gas with ultrahigh precision. Data from Iceland, Germany, United States (Yellowstone, Salton Sea), Costa Rica, and Chile show that subsurface isotope fractionation within hydrothermal systems is a globally pervasive and previously unrecognized process causing substantial nonradiogenic Ar-Kr-Xe isotope variations. Quantitatively accounting for this process is vital for accurately interpreting mantle-derived volatile (e.g., noble gas and nitrogen) signals, with profound implications for our understanding of terrestrial volatile evolution.
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Affiliation(s)
- David V. Bekaert
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
- Université de Lorraine, CNRS, CRPG, F-54000 Nancy, France
| | - Peter H. Barry
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
| | - Michael W. Broadley
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
- Université de Lorraine, CNRS, CRPG, F-54000 Nancy, France
| | - David J. Byrne
- Université de Lorraine, CNRS, CRPG, F-54000 Nancy, France
| | - Bernard Marty
- Université de Lorraine, CNRS, CRPG, F-54000 Nancy, France
| | - Carlos J. Ramírez
- Servicio Geológico Ambiental (SeGeoAm) Heredia, Santo Domingo, Costa Rica
| | - J. Maarten de Moor
- Observatorio Vulcanológico y Sismológico de Costa Rica Universidad Nacional, Heredia, Costa Rica
- Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87106, USA
| | - Alejandro Rodriguez
- Observatorio Vulcanológico y Sismológico de Costa Rica Universidad Nacional, Heredia, Costa Rica
| | - Michael R. Hudak
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
| | - Adam V. Subhas
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
| | | | - Andri Stefánsson
- NordVulk, Institute of Earth Sciences, University of Iceland, Reykjavík, Iceland
| | - Antonio Caracausi
- Instituto Nazionale di Geofisica e Vulcanologia, Sezione di Palermo, 90146 Palermo, Italy
- University of Salamanca, Salamanca, Spain
| | - Karen G. Lloyd
- Microbiology Department, University of Tennessee, Knoxville, TN 37996, USA
| | - Donato Giovannelli
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
- Department of Biology, University of Naples Federico II, Naples, Italy
- Institute for Marine Biological and Biotechnological Resources, National Research Council of Italy, Ancona, Italy
- Department of Marine and Coastal Science, Rutgers University, New Brunswick, NJ 08901, USA
| | - Alan M. Seltzer
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
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Natural Radioactivity and Chemical Evolution on the Early Earth: Prebiotic Chemistry and Oxygenation. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27238584. [PMID: 36500676 PMCID: PMC9740107 DOI: 10.3390/molecules27238584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 11/30/2022] [Accepted: 12/01/2022] [Indexed: 12/12/2022]
Abstract
It is generally recognized that the evolution of the early Earth was affected by an external energy source: radiation from the early Sun. The hypothesis about the important role of natural radioactivity, as a source of internal energy in the evolution of the early Earth, is considered and substantiated in this work. The decay of the long-lived isotopes 232Th, 238U, 235U, and 40K in the Global Ocean initiated the oxygenation of the hydro- and atmosphere, and the abiogenesis. The content of isotopes in the ocean and the kinetics of their decay, the values of the absorbed dose and dose rate, and the efficiency of sea water radiolysis, as a function of time, were calculated. The ocean served as both a "reservoir" that collected components of the early atmosphere and products of their transformations, and a "converter" in which further chemical reactions of these compounds took place. Radical mechanisms were proposed for the formation of simple amino acids, sugars, and nitrogen bases, i.e., the key structures of all living things, and also for the formation of oxygen. The calculation results confirm the possible important role of natural radioactivity in the evolution of terrestrial matter, and the emergence of life.
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3
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Teske J. Three types of planets orbit red dwarfs. Science 2022; 377:1156-1157. [PMID: 36074836 DOI: 10.1126/science.add7175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Precise densities of red dwarf exoplanets help distinguish potential "water worlds".
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Affiliation(s)
- Johanna Teske
- Earth and Planets Laboratory, Carnegie Institution for Science, Washington, DC 20015, USA
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Nitrogen isotope evidence for Earth's heterogeneous accretion of volatiles. Nat Commun 2022; 13:4769. [PMID: 35970934 PMCID: PMC9378614 DOI: 10.1038/s41467-022-32516-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 07/28/2022] [Indexed: 11/08/2022] Open
Abstract
The origin of major volatiles nitrogen, carbon, hydrogen, and sulfur in planets is critical for understanding planetary accretion, differentiation, and habitability. However, the detailed process for the origin of Earth's major volatiles remains unresolved. Nitrogen shows large isotopic fractionations among geochemical and cosmochemical reservoirs, which could be used to place tight constraints on Earth's volatile accretion process. Here we experimentally determine N-partitioning and -isotopic fractionation between planetary cores and silicate mantles. We show that the core/mantle N-isotopic fractionation factors, ranging from -4‰ to +10‰, are strongly controlled by oxygen fugacity, and the core/mantle N-partitioning is a multi-function of oxygen fugacity, temperature, pressure, and compositions of the core and mantle. After applying N-partitioning and -isotopic fractionation in a planetary accretion and core-mantle differentiation model, we find that the N-budget and -isotopic composition of Earth's crust plus atmosphere, silicate mantle, and the mantle source of oceanic island basalts are best explained by Earth's early accretion of enstatite chondrite-like impactors, followed by accretion of increasingly oxidized impactors and minimal CI chondrite-like materials before and during the Moon-forming giant impact. Such a heterogeneous accretion process can also explain the carbon-hydrogen-sulfur budget in the bulk silicate Earth. The Earth may thus have acquired its major volatile inventory heterogeneously during the main accretion phase.
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Rezaei‐Ghaleh N. Water Dynamics in Highly Concentrated Salt Solutions: A Multi‐Nuclear NMR Approach. Chemistry 2022; 11:e202200080. [PMID: 35642137 PMCID: PMC9156811 DOI: 10.1002/open.202200080] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/06/2022] [Indexed: 01/14/2023]
Abstract
Living cells often contain compartments with high concentration of charged biomolecules. A key question pertinent to the function of biomolecules is how water dynamics are affected by interaction with charged molecules. Here, we study the dynamical behavior of water in an extreme condition, that is, in saturated salt solutions, where nearly all water molecules are located within the first hydration layer of ions. To facilitate disentangling the effects of cations and anions, our study is focused on alkali chloride solutions. Following a multi‐nuclear NMR approach enabling direct monitoring of protons and the quadrupolar nuclei 7Li, 17O, 23Na, 35Cl, 87Rb and 133Cs, we investigate how the translational and rotational mobility of water molecules, chloride anion and corresponding cations are affected within the constrained environment of saturated solutions. Our results indicate that water molecules preserve a large level of mobility within saturated alkali chloride solutions that is significantly independent of adjacent ions.
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Affiliation(s)
- Nasrollah Rezaei‐Ghaleh
- Institute of Physical Biology Heinrich Heine University Düsseldorf Universitätsstrasse 1 40225 Düsseldorf Germany
- Institute of Biological Information Processing IBI-7: Structural Biochemistry Forschungszentrum Jülich 52428 Jülich Germany
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Ershov BG. Important role of seawater radiolysis of the World Ocean in the chemical evolution of the early Earth. Radiat Phys Chem Oxf Engl 1993 2022. [DOI: 10.1016/j.radphyschem.2022.109959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Grewal DS, Dasgupta R, Hough T, Farnell A. Rates of protoplanetary accretion and differentiation set nitrogen budget of rocky planets. NATURE GEOSCIENCE 2021; 14:369-376. [PMID: 34163536 PMCID: PMC8216213 DOI: 10.1038/s41561-021-00733-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 03/10/2021] [Indexed: 06/13/2023]
Abstract
The effect of protoplanetary differentiation on the fate of life-essential volatiles like nitrogen and carbon and its subsequent effect on the dynamics of planetary growth is unknown. Because the dissolution of nitrogen in magma oceans depends on its partial pressure and oxygen fugacity, it is an ideal proxy to track volatile re-distribution in protoplanets as a function of their sizes and growth zones. Using high pressure-temperature experiments in graphite-undersaturated conditions, here we show that the siderophile (iron-loving) character of nitrogen is an order of magnitude higher than previous estimates across a wide range of oxygen fugacity. The experimental data combined with metal-silicate-atmosphere fractionation models suggest that asteroid-sized protoplanets, and planetary embryos that grew from them, were nitrogen-depleted. However, protoplanets that grew to planetary embryo-size before undergoing differentiation had nitrogen-rich cores and nitrogen-poor silicate reservoirs. Bulk silicate reservoirs of large Earth-like planets attained nitrogen from the cores of latter type of planetary embryos. Therefore, to satisfy the volatile budgets of Earth-like planets during the main stage of their growth, the timescales of planetary embryo accretion had to be shorter than their differentiation timescales, i.e., Moon- to Mars-sized planetary embryos grew rapidly within ~1-2 Myrs of the Solar System's formation.
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Affiliation(s)
- Damanveer S. Grewal
- Department of Earth, Environmental, and Planetary Sciences, Rice University, 6100 Main Street, MS 126, Houston, TX 77005, USA
| | - Rajdeep Dasgupta
- Department of Earth, Environmental, and Planetary Sciences, Rice University, 6100 Main Street, MS 126, Houston, TX 77005, USA
| | - Taylor Hough
- Department of Earth, Environmental, and Planetary Sciences, Rice University, 6100 Main Street, MS 126, Houston, TX 77005, USA
| | - Alexandra Farnell
- Department of Earth, Environmental, and Planetary Sciences, Rice University, 6100 Main Street, MS 126, Houston, TX 77005, USA
- St. John’s School, 2401 Claremont Ln, Houston, TX 77019, USA
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Goodrich CA, Sanborn ME, Yin QZ, Kohl I, Frank D, Daly RT, Walsh KJ, Zolensky ME, Young ERD, Jenniskens P, Shaddad MH. Chromium Isotopic Evidence for Mixing of NC and CC Reservoirs in Polymict Ureilites: Implications for Dynamical Models of the Early Solar System. THE PLANETARY SCIENCE JOURNAL 2021; 2:13. [PMID: 33681766 PMCID: PMC7931809 DOI: 10.3847/psj/abd258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Nucleosynthetic isotope anomalies show that the first few million years of solar system history were characterized by two distinct cosmochemical reservoirs, CC (carbonaceous chondrites and related differentiated meteorites) and NC (the terrestrial planets and all other groups of chondrites and differentiated meteorites), widely interpreted to correspond to the outer and inner solar system, respectively. At some point, however, bulk CC and NC materials became mixed, and several dynamical models offer explanations for how and when this occurred. We use xenoliths of CC materials in polymict ureilite (NC) breccias to test the applicability of such models. Polymict ureilites represent regolith on ureilitic asteroids but contain carbonaceous chondrite-like xenoliths. We present the first 54Cr isotope data for such clasts, which, combined with oxygen and hydrogen isotopes, show that they are unique CC materials that became mixed with NC materials in these breccias. It has been suggested that such xenoliths were implanted into ureilites by outer solar system bodies migrating into the inner solar system during the gaseous disk phase ~3-5 Myr after CAI, as in the "Grand Tack" model. However, combined textural, petrologic, and spectroscopic observations suggest that they were added to ureilitic regolith at ~50-60 Myr after CAI, along with ordinary, enstatite, and Rumuruti-type chondrites, as a result of breakup of multiple parent bodies in the asteroid belt at this time. This is consistent with models for an early instability of the giant planets. The C-type asteroids from which the xenoliths were derived were already present in inner solar system orbits.
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Affiliation(s)
- Cyrena A Goodrich
- Lunar and Planetary Institute, Universities Space Research Association, 3600 Bay Area Blvd, Houston, TX 77058 USA
| | - Matthew E Sanborn
- Department of Earth and Planetary Sciences, University of California at Davis, Davis, CA 95616 USA
| | - Qing-Zhu Yin
- Department of Earth and Planetary Sciences, University of California at Davis, Davis, CA 95616 USA
| | - Issaku Kohl
- Department of Earth and Planetary Sciences, University of California at Los Angeles, 595 Charles Young Drive East, Los Angeles, CA 90095 USA
| | - David Frank
- Hawai'i Institute of Geophysics and Planetology, Department of Earth Sciences, University of Hawai'i at Mānoa, Honolulu HI 96822 USA
| | - R Terik Daly
- The Johns Hopkins University Applied Physics Laboratory 11100 Johns Hopkins Road
| | - Kevin J Walsh
- Southwest Research Institute, 1050 Walnut St. Suite 300, Boulder, CO 80302 USA
| | - Michael E Zolensky
- Astromaterials Research and Exploration Science, NASA-Johnson Space Center Houston, TX 77058 USA
| | - Edward R D Young
- Department of Earth and Planetary Sciences, University of California at Los Angeles, 595 Charles Young Drive East, Los Angeles, CA 90095 USA
| | | | - Muawia H Shaddad
- Physics Department, University of Khartoum, Khartoum 11115 Sudan
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Scott ERD, Krot AN, Sanders IS. Isotopic Dichotomy among Meteorites and Its Bearing on the Protoplanetary Disk. THE ASTROPHYSICAL JOURNAL 2018; 854:164. [PMID: 30842684 PMCID: PMC6398615 DOI: 10.3847/1538-4357/aaa5a5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Whole rock Δ17O and nucleosynthetic isotopic variations for chromium, titanium, nickel, and molybdenum in meteorites define two isotopically distinct populations: carbonaceous chondrites (CCs) and some achondrites, pallasites, and irons in one and all other chondrites and differentiated meteorites in the other. Since differentiated bodies accreted 1-3 Myr before the chondrites, the isotopic dichotomy cannot be attributed to temporal variations in the disk. Instead, the two populations were most likely separated in space, plausibly by proto-Jupiter. Formation of CCs outside Jupiter could account for their characteristic chemical and isotopic composition. The abundance of refractory inclusions in CCs can be explained if they were ejected by disk winds from near the Sun to the disk periphery where they spiraled inward due to gas drag. Once proto-Jupiter reached 10-20 M ⊕, its external pressure bump could have prevented millimeter- and centimeter-sized particles from reaching the inner disk. This scenario would account for the enrichment in CCs of refractory inclusions, refractory elements, and water. Chondrules in CCs show wide ranges in Δ17O as they formed in the presence of abundant 16O-rich refractory grains and 16O-poor ice particles. Chondrules in other chondrites (ordinary, E, R, and K groups) show relatively uniform, near-zero Δ17O values as refractory inclusions and ice were much less abundant in the inner solar system. The two populations were plausibly mixed together by the Grand Tack when Jupiter and Saturn migrated inward emptying and then repopulating the asteroid belt with roughly equal masses of planetesimals from inside and outside Jupiter's orbit (S- and C-type asteroids).
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Affiliation(s)
- Edward R D Scott
- Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, Honolulu, HI 96822, USA
| | - Alexander N Krot
- Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, Honolulu, HI 96822, USA
| | - Ian S Sanders
- Department of Geology, Trinity College, Dublin 2, Ireland
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O'D Alexander CM, McKeegan KD, Altwegg K. Water Reservoirs in Small Planetary Bodies: Meteorites, Asteroids, and Comets. SPACE SCIENCE REVIEWS 2018; 214:36. [PMID: 30842688 PMCID: PMC6398961 DOI: 10.1007/s11214-018-0474-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 01/11/2018] [Indexed: 06/09/2023]
Abstract
Asteroids and comets are the remnants of the swarm of planetesimals from which the planets ultimately formed, and they retain records of processes that operated prior to and during planet formation. They are also likely the sources of most of the water and other volatiles accreted by Earth. In this review, we discuss the nature and probable origins of asteroids and comets based on data from remote observations, in situ measurements by spacecraft, and laboratory analyses of meteorites derived from asteroids. The asteroidal parent bodies of meteorites formed ≤4 Ma after Solar System formation while there was still a gas disk present. It seems increasingly likely that the parent bodies of meteorites spectroscopically linked with the E-, S-, M- and V-type asteroids formed sunward of Jupiter's orbit, while those associated with C- and, possibly, D-type asteroids formed further out, beyond Jupiter but probably not beyond Saturn's orbit. Comets formed further from the Sun than any of the meteorite parent bodies, and retain much higher abundances of interstellar material. CI and CM group meteorites are probably related to the most common C-type asteroids, and based on isotopic evidence they, rather than comets, are the most likely sources of the H and N accreted by the terrestrial planets. However, comets may have been major sources of the noble gases accreted by Earth and Venus. Possible constraints that these observations can place on models of giant planet formation and migration are explored.
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Affiliation(s)
- Conel M O'D Alexander
- Dept. Terrestrial Magnetism, Carnegie Institution for Science, 5241 Broad Branch Road NW, Washington, DC 20015, USA. . Tel. (202) 478 8478
| | - Kevin D McKeegan
- Department of Earth, Planetary, and Space Sciences, University of California-Los Angeles, Los Angeles, CA 90095-1567, USA.
| | - Kathrin Altwegg
- Physikalisches Institut, University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland.
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Wright IP, Sheridan S, Morgan GH, Barber SJ, Morse AD. On the attempts to measure water (and other volatiles) directly at the surface of a comet. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2017; 375:rsta.2015.0385. [PMID: 28416724 PMCID: PMC5394252 DOI: 10.1098/rsta.2015.0385] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/14/2016] [Indexed: 05/23/2023]
Abstract
The Ptolemy instrument on the Philae lander (of the Rosetta space mission) was able to make measurements of the major volatiles, water, carbon monoxide and carbon dioxide, directly at the surface of comet 67P/Churyumov-Gerasimenko. We give some background to the mission and highlight those instruments that have already given insights into the notion of water in comets, and which will continue to do so as more results are either acquired or more fully interpreted. On the basis of our results, we show how comets may in fact be heterogeneous over their surface, and how surface measurements can be used in a quest to comprehend the daily cycles of processes that affect the evolution of comets.This article is part of the themed issue 'The origin, history and role of water in the evolution of the inner Solar System'.
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Affiliation(s)
- I P Wright
- Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK
| | - S Sheridan
- Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK
| | - G H Morgan
- Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK
| | - S J Barber
- Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK
| | - A D Morse
- Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK
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12
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Russell SS, Ballentine CJ, Grady MM. The origin, history and role of water in the evolution of the inner Solar System. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2017; 375:rsta.2017.0108. [PMID: 28416731 PMCID: PMC5394259 DOI: 10.1098/rsta.2017.0108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/21/2017] [Indexed: 05/06/2023]
Affiliation(s)
- Sara S Russell
- Department of Earth Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD, UK
- Open University, Walton Hall, Milton Keynes MK7 6AA, UK
| | | | - Monica M Grady
- Department of Earth Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD, UK
- Open University, Walton Hall, Milton Keynes MK7 6AA, UK
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