Sulfide petrology of four nakhlites: Northwest Africa 817, Northwest Africa 998, Nakhla, and Governador Valadares
Identifieur interne : 001A01 ( Istex/Corpus ); précédent : 001A00; suivant : 001A02Sulfide petrology of four nakhlites: Northwest Africa 817, Northwest Africa 998, Nakhla, and Governador Valadares
Auteurs : Vincent Chevrier ; Jean-Pierre Lorand ; Violaine SautterSource :
- Meteoritics & Planetary Science [ 1086-9379 ] ; 2011-06.
Abstract
Abstract– The nakhlites contain small proportions of Cu‐Fe‐Ni sulfide minerals; we have studied these sulfides in Northwest Africa (NWA) 998, Nakhla, Governador Valadares, and NWA 817 with optical microscopy, scanning electron microscope, and electron microprobe. Modal abundances of magmatic sulfides, as estimated by image analysis on thin section, are uniformly low (0.02 to 0.05 ± 0.03 vol%), i.e., a factor 5 lower than in shergottites. Sulfides occur within the glassy mesostasis, as composite two‐phase Fe‐Ti oxide‐sulfide grains, intimately associated with interstitial grains or locally enclosed in postcumulus melt inclusions (e.g., Governador Valadares) in olivine. They exhibit a uniform low‐Ni monoclinic pyrrhotite composition ± chalcopyrite. There is a gradation of sulfide grain sizes and textures across the nakhlites flow(s): droplets in NWA 817; resorbed blebs in Governador Valadares; more massive, true intercumulus blebs in Nakhla and NWA 998. These nakhlites also show evidence for sulfide weathering. Hot desert finds (e.g., NWA 998 and NWA 817) show a few percent fracture‐filling iron (oxy) hydroxides of likely terrestrial origin. Original sulfides are 50% altered in our NWA 998 section, with iron (oxy) hydroxides at grain boundaries and as complete pseudomorphs. The compositions of unaltered pyrrhotites are homogeneous, close to that of the monoclinic endmember Fe7S8, and are too sulfur‐rich to have been in chemical equilibrium with the late magmatic redox state fixed by the fayalite‐magnetite‐quartz buffer. Therefore, the compositions of the pyrrhotites must have been altered during the later stages of magmatic crystallization, by assimilation of S‐rich regolith and hydrothermal circulation.
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DOI: 10.1111/j.1945-5100.2011.01189.x
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Keck Laboratory for Space and Planetary Simulation, Arkansas Center for Space and Planetary Science, MUSE 202, University of Arkansas, Fayetteville, Arkansas 72701, USA</mods:affiliation></affiliation></author><author><name sortKey="Lorand, Jean Ierre" sort="Lorand, Jean Ierre" uniqKey="Lorand J" first="Jean-Pierre" last="Lorand">Jean-Pierre Lorand</name><affiliation><mods:affiliation>Laboratoire de Minéralogie et Cosmochimie, Muséum National d’Histoire Naturelle, CNRS UMR 7202, 61 Rue Buffon, 75005 Paris, France</mods:affiliation></affiliation></author><author><name sortKey="Sautter, Violaine" sort="Sautter, Violaine" uniqKey="Sautter V" first="Violaine" last="Sautter">Violaine Sautter</name><affiliation><mods:affiliation>Laboratoire de Minéralogie et Cosmochimie, Muséum National d’Histoire Naturelle, CNRS UMR 7202, 61 Rue Buffon, 75005 Paris, France</mods:affiliation></affiliation></author></titleStmt><publicationStmt><idno type="wicri:source">ISTEX</idno><idno type="RBID">ISTEX:B2E8B215DAF9624C1036B5E91E4BC4B96BEA5EE9</idno><date when="2011" year="2011">2011</date><idno type="doi">10.1111/j.1945-5100.2011.01189.x</idno><idno type="url">https://api.istex.fr/document/B2E8B215DAF9624C1036B5E91E4BC4B96BEA5EE9/fulltext/pdf</idno><idno type="wicri:Area/Istex/Corpus">001A01</idno><idno type="wicri:explorRef" wicri:stream="Istex" wicri:step="Corpus" wicri:corpus="ISTEX">001A01</idno></publicationStmt><sourceDesc><biblStruct><analytic><title level="a" type="main" xml:lang="en">Sulfide petrology of four nakhlites: Northwest Africa 817, Northwest Africa 998, Nakhla, and Governador Valadares</title><author><name sortKey="Chevrier, Vincent" sort="Chevrier, Vincent" uniqKey="Chevrier V" first="Vincent" last="Chevrier">Vincent Chevrier</name><affiliation><mods:affiliation>W.M. Keck Laboratory for Space and Planetary Simulation, Arkansas Center for Space and Planetary Science, MUSE 202, University of Arkansas, Fayetteville, Arkansas 72701, USA</mods:affiliation></affiliation></author><author><name sortKey="Lorand, Jean Ierre" sort="Lorand, Jean Ierre" uniqKey="Lorand J" first="Jean-Pierre" last="Lorand">Jean-Pierre Lorand</name><affiliation><mods:affiliation>Laboratoire de Minéralogie et Cosmochimie, Muséum National d’Histoire Naturelle, CNRS UMR 7202, 61 Rue Buffon, 75005 Paris, France</mods:affiliation></affiliation></author><author><name sortKey="Sautter, Violaine" sort="Sautter, Violaine" uniqKey="Sautter V" first="Violaine" last="Sautter">Violaine Sautter</name><affiliation><mods:affiliation>Laboratoire de Minéralogie et Cosmochimie, Muséum National d’Histoire Naturelle, CNRS UMR 7202, 61 Rue Buffon, 75005 Paris, France</mods:affiliation></affiliation></author></analytic><monogr></monogr><series><title level="j">Meteoritics & Planetary Science</title><idno type="ISSN">1086-9379</idno><idno type="eISSN">1945-5100</idno><imprint><publisher>Blackwell Publishing Ltd</publisher><pubPlace>Oxford, UK</pubPlace><date type="published" when="2011-06">2011-06</date><biblScope unit="volume">46</biblScope><biblScope unit="issue">6</biblScope><biblScope unit="page" from="769">769</biblScope><biblScope unit="page" to="784">784</biblScope></imprint><idno type="ISSN">1086-9379</idno></series><idno type="istex">B2E8B215DAF9624C1036B5E91E4BC4B96BEA5EE9</idno><idno type="DOI">10.1111/j.1945-5100.2011.01189.x</idno><idno type="ArticleID">MAPS1189</idno></biblStruct></sourceDesc><seriesStmt><idno type="ISSN">1086-9379</idno></seriesStmt></fileDesc><profileDesc><textClass></textClass><langUsage><language ident="en">en</language></langUsage></profileDesc></teiHeader><front><div type="abstract">Abstract– The nakhlites contain small proportions of Cu‐Fe‐Ni sulfide minerals; we have studied these sulfides in Northwest Africa (NWA) 998, Nakhla, Governador Valadares, and NWA 817 with optical microscopy, scanning electron microscope, and electron microprobe. Modal abundances of magmatic sulfides, as estimated by image analysis on thin section, are uniformly low (0.02 to 0.05 ± 0.03 vol%), i.e., a factor 5 lower than in shergottites. Sulfides occur within the glassy mesostasis, as composite two‐phase Fe‐Ti oxide‐sulfide grains, intimately associated with interstitial grains or locally enclosed in postcumulus melt inclusions (e.g., Governador Valadares) in olivine. They exhibit a uniform low‐Ni monoclinic pyrrhotite composition ± chalcopyrite. There is a gradation of sulfide grain sizes and textures across the nakhlites flow(s): droplets in NWA 817; resorbed blebs in Governador Valadares; more massive, true intercumulus blebs in Nakhla and NWA 998. These nakhlites also show evidence for sulfide weathering. Hot desert finds (e.g., NWA 998 and NWA 817) show a few percent fracture‐filling iron (oxy) hydroxides of likely terrestrial origin. Original sulfides are 50% altered in our NWA 998 section, with iron (oxy) hydroxides at grain boundaries and as complete pseudomorphs. The compositions of unaltered pyrrhotites are homogeneous, close to that of the monoclinic endmember Fe7S8, and are too sulfur‐rich to have been in chemical equilibrium with the late magmatic redox state fixed by the fayalite‐magnetite‐quartz buffer. Therefore, the compositions of the pyrrhotites must have been altered during the later stages of magmatic crystallization, by assimilation of S‐rich regolith and hydrothermal circulation.</div></front></TEI><istex><corpusName>wiley</corpusName><author><json:item><name>Vincent CHEVRIER</name><affiliations><json:string>W.M. Keck Laboratory for Space and Planetary Simulation, Arkansas Center for Space and Planetary Science, MUSE 202, University of Arkansas, Fayetteville, Arkansas 72701, USA</json:string></affiliations></json:item><json:item><name>Jean‐Pierre LORAND</name><affiliations><json:string>Laboratoire de Minéralogie et Cosmochimie, Muséum National d’Histoire Naturelle, CNRS UMR 7202, 61 Rue Buffon, 75005 Paris, France</json:string></affiliations></json:item><json:item><name>Violaine SAUTTER</name><affiliations><json:string>Laboratoire de Minéralogie et Cosmochimie, Muséum National d’Histoire Naturelle, CNRS UMR 7202, 61 Rue Buffon, 75005 Paris, France</json:string></affiliations></json:item></author><articleId><json:string>MAPS1189</json:string></articleId><language><json:string>eng</json:string></language><originalGenre><json:string>article</json:string></originalGenre><abstract>Abstract– The nakhlites contain small proportions of Cu‐Fe‐Ni sulfide minerals; we have studied these sulfides in Northwest Africa (NWA) 998, Nakhla, Governador Valadares, and NWA 817 with optical microscopy, scanning electron microscope, and electron microprobe. Modal abundances of magmatic sulfides, as estimated by image analysis on thin section, are uniformly low (0.02 to 0.05 ± 0.03 vol%), i.e., a factor 5 lower than in shergottites. Sulfides occur within the glassy mesostasis, as composite two‐phase Fe‐Ti oxide‐sulfide grains, intimately associated with interstitial grains or locally enclosed in postcumulus melt inclusions (e.g., Governador Valadares) in olivine. They exhibit a uniform low‐Ni monoclinic pyrrhotite composition ± chalcopyrite. There is a gradation of sulfide grain sizes and textures across the nakhlites flow(s): droplets in NWA 817; resorbed blebs in Governador Valadares; more massive, true intercumulus blebs in Nakhla and NWA 998. These nakhlites also show evidence for sulfide weathering. Hot desert finds (e.g., NWA 998 and NWA 817) show a few percent fracture‐filling iron (oxy) hydroxides of likely terrestrial origin. Original sulfides are 50% altered in our NWA 998 section, with iron (oxy) hydroxides at grain boundaries and as complete pseudomorphs. The compositions of unaltered pyrrhotites are homogeneous, close to that of the monoclinic endmember Fe7S8, and are too sulfur‐rich to have been in chemical equilibrium with the late magmatic redox state fixed by the fayalite‐magnetite‐quartz buffer. 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E‐mail:</p></note><affiliation>W.M. Keck Laboratory for Space and Planetary Simulation, Arkansas Center for Space and Planetary Science, MUSE 202, University of Arkansas, Fayetteville, Arkansas 72701, USA</affiliation></author><author xml:id="author-2"><persName><forename type="first">Jean‐Pierre</forename><surname>LORAND</surname></persName><affiliation>Laboratoire de Minéralogie et Cosmochimie, Muséum National d’Histoire Naturelle, CNRS UMR 7202, 61 Rue Buffon, 75005 Paris, France</affiliation></author><author xml:id="author-3"><persName><forename type="first">Violaine</forename><surname>SAUTTER</surname></persName><affiliation>Laboratoire de Minéralogie et Cosmochimie, Muséum National d’Histoire Naturelle, CNRS UMR 7202, 61 Rue Buffon, 75005 Paris, France</affiliation></author></analytic><monogr><title level="j">Meteoritics & Planetary Science</title><idno type="pISSN">1086-9379</idno><idno type="eISSN">1945-5100</idno><idno type="DOI">10.1111/(ISSN)1945-5100</idno><imprint><publisher>Blackwell Publishing Ltd</publisher><pubPlace>Oxford, UK</pubPlace><date type="published" when="2011-06"></date><biblScope unit="volume">46</biblScope><biblScope unit="issue">6</biblScope><biblScope unit="page" from="769">769</biblScope><biblScope unit="page" to="784">784</biblScope></imprint></monogr><idno type="istex">B2E8B215DAF9624C1036B5E91E4BC4B96BEA5EE9</idno><idno type="DOI">10.1111/j.1945-5100.2011.01189.x</idno><idno type="ArticleID">MAPS1189</idno></biblStruct></sourceDesc></fileDesc><profileDesc><creation><date>2011</date></creation><langUsage><language ident="en">en</language></langUsage><abstract><p>Abstract– The nakhlites contain small proportions of Cu‐Fe‐Ni sulfide minerals; we have studied these sulfides in Northwest Africa (NWA) 998, Nakhla, Governador Valadares, and NWA 817 with optical microscopy, scanning electron microscope, and electron microprobe. Modal abundances of magmatic sulfides, as estimated by image analysis on thin section, are uniformly low (0.02 to 0.05 ± 0.03 vol%), i.e., a factor 5 lower than in shergottites. Sulfides occur within the glassy mesostasis, as composite two‐phase Fe‐Ti oxide‐sulfide grains, intimately associated with interstitial grains or locally enclosed in postcumulus melt inclusions (e.g., Governador Valadares) in olivine. They exhibit a uniform low‐Ni monoclinic pyrrhotite composition ± chalcopyrite. There is a gradation of sulfide grain sizes and textures across the nakhlites flow(s): droplets in NWA 817; resorbed blebs in Governador Valadares; more massive, true intercumulus blebs in Nakhla and NWA 998. These nakhlites also show evidence for sulfide weathering. Hot desert finds (e.g., NWA 998 and NWA 817) show a few percent fracture‐filling iron (oxy) hydroxides of likely terrestrial origin. Original sulfides are 50% altered in our NWA 998 section, with iron (oxy) hydroxides at grain boundaries and as complete pseudomorphs. The compositions of unaltered pyrrhotites are homogeneous, close to that of the monoclinic endmember Fe7S8, and are too sulfur‐rich to have been in chemical equilibrium with the late magmatic redox state fixed by the fayalite‐magnetite‐quartz buffer. Therefore, the compositions of the pyrrhotites must have been altered during the later stages of magmatic crystallization, by assimilation of S‐rich regolith and hydrothermal circulation.</p></abstract></profileDesc><revisionDesc><change when="2011-06">Published</change></revisionDesc></teiHeader></istex:fulltextTEI><json:item><original>false</original><mimetype>text/plain</mimetype><extension>txt</extension><uri>https://api.istex.fr/document/B2E8B215DAF9624C1036B5E91E4BC4B96BEA5EE9/fulltext/txt</uri></json:item></fulltext><metadata><istex:metadataXml wicri:clean="Wiley, elements deleted: body"><istex:xmlDeclaration>version="1.0" encoding="UTF-8" standalone="yes"</istex:xmlDeclaration><istex:document><component version="2.0" type="serialArticle" xml:lang="en"><header><publicationMeta level="product"><publisherInfo><publisherName>Blackwell Publishing Ltd</publisherName><publisherLoc>Oxford, UK</publisherLoc></publisherInfo><doi origin="wiley" registered="yes">10.1111/(ISSN)1945-5100</doi><issn type="print">1086-9379</issn><issn type="electronic">1945-5100</issn><idGroup><id type="product" value="MAPS"></id><id type="publisherDivision" value="ST"></id></idGroup><titleGroup><title type="main" sort="METEORITICS AND PLANETARY SCIENCE">Meteoritics & Planetary Science</title></titleGroup></publicationMeta><publicationMeta level="part" position="06106"><doi origin="wiley">10.1111/maps.2011.46.issue-6</doi><numberingGroup><numbering type="journalVolume" number="46">46</numbering><numbering type="journalIssue" number="6">6</numbering></numberingGroup><coverDate startDate="2011-06">June 2011</coverDate></publicationMeta><publicationMeta level="unit" type="article" position="1" status="forIssue"><doi origin="wiley">10.1111/j.1945-5100.2011.01189.x</doi><idGroup><id type="unit" value="MAPS1189"></id></idGroup><countGroup><count type="pageTotal" number="16"></count></countGroup><titleGroup><title type="tocHeading1">Articles</title></titleGroup><copyright>© The Meteoritical Society, 2011</copyright><eventGroup><event type="xmlConverted" agent="Converter:BPG_TO_WML3G version:2.5.2 mode:FullText" date="2011-06-22"></event><event type="publishedOnlineEarlyUnpaginated" date="2011-04-12"></event><event type="publishedOnlineFinalForm" date="2011-06-13"></event><event type="firstOnline" date="2011-04-12"></event><event type="xmlConverted" agent="Converter:WILEY_ML3G_TO_WILEY_ML3GV2 version:4.0.1" date="2014-03-20"></event><event type="xmlConverted" agent="Converter:WML3G_To_WML3G version:4.1.7 mode:FullText,remove_FC" date="2014-10-31"></event></eventGroup><numberingGroup><numbering type="pageFirst" number="769">769</numbering><numbering type="pageLast" number="784">784</numbering></numberingGroup><correspondenceTo> Corresponding author. E‐mail: <email>vchevrie@uark.edu</email></correspondenceTo><linkGroup><link type="toTypesetVersion" href="file:MAPS.MAPS1189.pdf"></link></linkGroup></publicationMeta><contentMeta><unparsedEditorialHistory>(Received 24 March 2010; revision accepted 16 January 2011)</unparsedEditorialHistory><countGroup><count type="figureTotal" number="6"></count><count type="tableTotal" number="7"></count></countGroup><titleGroup><title type="main">Sulfide petrology of four nakhlites: Northwest Africa 817, Northwest Africa 998, Nakhla, and Governador Valadares</title><title type="shortAuthors">V. Chevrier et al.</title><title type="short">Sulfide petrology in nakhlites</title></titleGroup><creators><creator creatorRole="author" xml:id="cr1" affiliationRef="#a1" corresponding="yes"><personName><givenNames>Vincent</givenNames><familyName>CHEVRIER</familyName></personName></creator><creator creatorRole="author" xml:id="cr2" affiliationRef="#a2"><personName><givenNames>Jean‐Pierre</givenNames><familyName>LORAND</familyName></personName></creator><creator creatorRole="author" xml:id="cr3" affiliationRef="#a2"><personName><givenNames>Violaine</givenNames><familyName>SAUTTER</familyName></personName></creator></creators><affiliationGroup><affiliation xml:id="a1" countryCode="US"><unparsedAffiliation>W.M. Keck Laboratory for Space and Planetary Simulation, Arkansas Center for Space and Planetary Science, MUSE 202, University of Arkansas, Fayetteville, Arkansas 72701, USA</unparsedAffiliation></affiliation><affiliation xml:id="a2" countryCode="FR"><unparsedAffiliation>Laboratoire de Minéralogie et Cosmochimie, Muséum National d’Histoire Naturelle, CNRS UMR 7202, 61 Rue Buffon, 75005 Paris, France</unparsedAffiliation></affiliation></affiliationGroup><abstractGroup><abstract type="main" xml:lang="en"><p><b>Abstract–</b> The nakhlites contain small proportions of Cu‐Fe‐Ni sulfide minerals; we have studied these sulfides in Northwest Africa (NWA) 998, Nakhla, Governador Valadares, and NWA 817 with optical microscopy, scanning electron microscope, and electron microprobe. Modal abundances of magmatic sulfides, as estimated by image analysis on thin section, are uniformly low (0.02 to 0.05 ± 0.03 vol%), i.e., a factor 5 lower than in shergottites. Sulfides occur within the glassy mesostasis, as composite two‐phase Fe‐Ti oxide‐sulfide grains, intimately associated with interstitial grains or locally enclosed in postcumulus melt inclusions (e.g., Governador Valadares) in olivine. They exhibit a uniform low‐Ni monoclinic pyrrhotite composition ± chalcopyrite. There is a gradation of sulfide grain sizes and textures across the nakhlites flow(s): droplets in NWA 817; resorbed blebs in Governador Valadares; more massive, true intercumulus blebs in Nakhla and NWA 998. These nakhlites also show evidence for sulfide weathering. Hot desert finds (e.g., NWA 998 and NWA 817) show a few percent fracture‐filling iron (oxy) hydroxides of likely terrestrial origin. Original sulfides are 50% altered in our NWA 998 section, with iron (oxy) hydroxides at grain boundaries and as complete pseudomorphs. The compositions of unaltered pyrrhotites are homogeneous, close to that of the monoclinic endmember Fe<sub>7</sub>S<sub>8</sub>, and are too sulfur‐rich to have been in chemical equilibrium with the late magmatic redox state fixed by the fayalite‐magnetite‐quartz buffer. Therefore, the compositions of the pyrrhotites must have been altered during the later stages of magmatic crystallization, by assimilation of S‐rich regolith and hydrothermal circulation.</p></abstract></abstractGroup></contentMeta></header></component></istex:document></istex:metadataXml><mods version="3.6"><titleInfo lang="en"><title>Sulfide petrology of four nakhlites: Northwest Africa 817, Northwest Africa 998, Nakhla, and Governador Valadares</title></titleInfo><titleInfo type="abbreviated" lang="en"><title>Sulfide petrology in nakhlites</title></titleInfo><titleInfo type="alternative" contentType="CDATA" lang="en"><title>Sulfide petrology of four nakhlites: Northwest Africa 817, Northwest Africa 998, Nakhla, and Governador Valadares</title></titleInfo><name type="personal"><namePart type="given">Vincent</namePart><namePart type="family">CHEVRIER</namePart><affiliation>W.M. Keck Laboratory for Space and Planetary Simulation, Arkansas Center for Space and Planetary Science, MUSE 202, University of Arkansas, Fayetteville, Arkansas 72701, USA</affiliation><description>Correspondence: Corresponding author. E‐mail: </description><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">Jean‐Pierre</namePart><namePart type="family">LORAND</namePart><affiliation>Laboratoire de Minéralogie et Cosmochimie, Muséum National d’Histoire Naturelle, CNRS UMR 7202, 61 Rue Buffon, 75005 Paris, France</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">Violaine</namePart><namePart type="family">SAUTTER</namePart><affiliation>Laboratoire de Minéralogie et Cosmochimie, Muséum National d’Histoire Naturelle, CNRS UMR 7202, 61 Rue Buffon, 75005 Paris, France</affiliation><role><roleTerm type="text">author</roleTerm></role></name><typeOfResource>text</typeOfResource><genre type="article" displayLabel="article"></genre><originInfo><publisher>Blackwell Publishing Ltd</publisher><place><placeTerm type="text">Oxford, UK</placeTerm></place><dateIssued encoding="w3cdtf">2011-06</dateIssued><edition>(Received 24 March 2010; revision accepted 16 January 2011)</edition><copyrightDate encoding="w3cdtf">2011</copyrightDate></originInfo><language><languageTerm type="code" authority="rfc3066">en</languageTerm><languageTerm type="code" authority="iso639-2b">eng</languageTerm></language><physicalDescription><internetMediaType>text/html</internetMediaType><extent unit="figures">6</extent><extent unit="tables">7</extent></physicalDescription><abstract>Abstract– The nakhlites contain small proportions of Cu‐Fe‐Ni sulfide minerals; we have studied these sulfides in Northwest Africa (NWA) 998, Nakhla, Governador Valadares, and NWA 817 with optical microscopy, scanning electron microscope, and electron microprobe. Modal abundances of magmatic sulfides, as estimated by image analysis on thin section, are uniformly low (0.02 to 0.05 ± 0.03 vol%), i.e., a factor 5 lower than in shergottites. Sulfides occur within the glassy mesostasis, as composite two‐phase Fe‐Ti oxide‐sulfide grains, intimately associated with interstitial grains or locally enclosed in postcumulus melt inclusions (e.g., Governador Valadares) in olivine. They exhibit a uniform low‐Ni monoclinic pyrrhotite composition ± chalcopyrite. There is a gradation of sulfide grain sizes and textures across the nakhlites flow(s): droplets in NWA 817; resorbed blebs in Governador Valadares; more massive, true intercumulus blebs in Nakhla and NWA 998. These nakhlites also show evidence for sulfide weathering. Hot desert finds (e.g., NWA 998 and NWA 817) show a few percent fracture‐filling iron (oxy) hydroxides of likely terrestrial origin. Original sulfides are 50% altered in our NWA 998 section, with iron (oxy) hydroxides at grain boundaries and as complete pseudomorphs. The compositions of unaltered pyrrhotites are homogeneous, close to that of the monoclinic endmember Fe7S8, and are too sulfur‐rich to have been in chemical equilibrium with the late magmatic redox state fixed by the fayalite‐magnetite‐quartz buffer. Therefore, the compositions of the pyrrhotites must have been altered during the later stages of magmatic crystallization, by assimilation of S‐rich regolith and hydrothermal circulation.</abstract><relatedItem type="host"><titleInfo><title>Meteoritics & Planetary Science</title></titleInfo><genre type="journal">journal</genre><identifier type="ISSN">1086-9379</identifier><identifier type="eISSN">1945-5100</identifier><identifier type="DOI">10.1111/(ISSN)1945-5100</identifier><identifier type="PublisherID">MAPS</identifier><part><date>2011</date><detail type="volume"><caption>vol.</caption><number>46</number></detail><detail type="issue"><caption>no.</caption><number>6</number></detail><extent unit="pages"><start>769</start><end>784</end><total>16</total></extent></part></relatedItem><identifier type="istex">B2E8B215DAF9624C1036B5E91E4BC4B96BEA5EE9</identifier><identifier type="DOI">10.1111/j.1945-5100.2011.01189.x</identifier><identifier type="ArticleID">MAPS1189</identifier><accessCondition type="use and reproduction" contentType="copyright">© The Meteoritical Society, 2011</accessCondition><recordInfo><recordContentSource>WILEY</recordContentSource><recordOrigin>Blackwell Publishing Ltd</recordOrigin></recordInfo></mods></metadata><serie></serie></istex></record>Pour manipuler ce document sous Unix (Dilib)
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