Three steps of serpentinization in an eclogitized oceanic serpentinization front (Lanzo Massif - Western Alps)
The Lanzo peridotite massif is a fragment of oceanic lithosphere generated in an ocean–continent transition context and eclogitized during alpine collision. Despite the subduction history, the massif has preserved its sedimentary oceanic cover, suggesting that it may have preserved its oceanic struc...
Gespeichert in:
| Veröffentlicht in: | Journal of metamorphic geology 2013-02, Vol.31 (2), p.165-186 |
|---|---|
| Hauptverfasser: | , , , , |
| Format: | Artikel |
| Sprache: | eng |
| Schlagworte: | |
| Online-Zugang: | Volltext |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| container_end_page | 186 |
|---|---|
| container_issue | 2 |
| container_start_page | 165 |
| container_title | Journal of metamorphic geology |
| container_volume | 31 |
| creator | DEBRET, B. NICOLLET, C. ANDREANI, M. SCHWARTZ, S. GODARD, M. |
| description | The Lanzo peridotite massif is a fragment of oceanic lithosphere generated in an ocean–continent transition context and eclogitized during alpine collision. Despite the subduction history, the massif has preserved its sedimentary oceanic cover, suggesting that it may have preserved its oceanic structure. It is an exceptional case for studying the evolution of a fragment of the lithosphere from its oceanization to its subduction and then exhumation. We present a field and petrological study retracing the different serpentinization episodes and their impact on the massif structure. The Lanzo massif is composed of slightly serpentinized peridotites ( |
| doi_str_mv | 10.1111/jmg.12008 |
| format | Article |
| fullrecord | <record><control><sourceid>proquest_hal_p</sourceid><recordid>TN_cdi_hal_primary_oai_HAL_hal_00823051v1</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><sourcerecordid>2882576711</sourcerecordid><originalsourceid>FETCH-LOGICAL-a4588-942b80926a6c8d22cda383bf2c5cd52fa006a589ef6c5107fc367d1086d73a423</originalsourceid><addsrcrecordid>eNp1kMtKAzEUhoMoWC8L3yDgRhejuUwymWUpWpWqIIrgJsRMoqljMiZTL316o_WyEM_mwOH7fw4fAFsY7eE8-9PHuz1MEBJLYIAZYQWmuFwGA0Q4Lcqa1KtgLaUpQpgSWg6Av7yPxsDUmy7BYGEysTO-d97NVe-Ch85D5aHRbbhzvZubBgZtlHf6L2pj8D3cmSg_D_BUpeQsLOC1yeXRw2Hbpd0NsGJVm8zm114HV4cHl6OjYnI-Ph4NJ4UqmRBFXZJbgWrCFdeiIUQ3igp6a4lmumHEKoS4YqI2lmuGUWU15VWDkeBNRVVJ6DrYXfTeq1Z20T2q-CaDcvJoOJEft2yIUMTwM87s9oLtYnia5W_lNMyiz-9JTAQVvKYY_zbqGFKKxv7UYiQ_1MusXn6qz-z-gn1xrXn7H5Qnp-PvRLFIuCzr9Seh4oPkFa2YvD4bywt6I27YCZcj-g4C15Oo</addsrcrecordid><sourcetype>Open Access Repository</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>1283869311</pqid></control><display><type>article</type><title>Three steps of serpentinization in an eclogitized oceanic serpentinization front (Lanzo Massif - Western Alps)</title><source>Access via Wiley Online Library</source><creator>DEBRET, B. ; NICOLLET, C. ; ANDREANI, M. ; SCHWARTZ, S. ; GODARD, M.</creator><creatorcontrib>DEBRET, B. ; NICOLLET, C. ; ANDREANI, M. ; SCHWARTZ, S. ; GODARD, M.</creatorcontrib><description>The Lanzo peridotite massif is a fragment of oceanic lithosphere generated in an ocean–continent transition context and eclogitized during alpine collision. Despite the subduction history, the massif has preserved its sedimentary oceanic cover, suggesting that it may have preserved its oceanic structure. It is an exceptional case for studying the evolution of a fragment of the lithosphere from its oceanization to its subduction and then exhumation. We present a field and petrological study retracing the different serpentinization episodes and their impact on the massif structure. The Lanzo massif is composed of slightly serpentinized peridotites (<20% serpentinization) surrounded by an envelope of foliated serpentinites (100% serpentinization) bordered by oceanic metabasalts and metasedimentary rocks. The limit between peridotites and serpentinites defines the front of serpentinization. This limit is sharp: it is marked by the presence of massive serpentinites (80% serpentinization) and, locally, by dykes of metagabbros and mylonitic gabbros. The deformation of these gabbros is contemporaneous with the emplacement of the magma. The presence of early lizardite in the peridotites testifies that serpentinization began during the oceanization, which is confirmed by the presence of meta‐ophicarbonates bordering the foliated serpentinite envelope. Two additional generations of serpentine occur in the ultramafic rocks. The first is a prograde antigorite that partially replaced the lizardite and the relict primary minerals of the peridotite during subduction, indicating that serpentinization is an active process at the ridge and in the subduction zone. Locally, this episode is followed by the deserpentinization of antigorite at peak P–T (estimated in eclogitized metagabbros at 2–2.5 GPa and 550–620 °C): it is marked by the crystallization of secondary olivine associated with chlorite and/or antigorite and of clinopyroxene, amphibole and chlorite assemblages. A second antigorite formed during exhumation partially to completely obliterating previous textures in the massive and foliated serpentinites. Serpentinites are an important component of the oceanic lithosphere generated in slow to ultraslow spreading settings, and in these settings, there is a serpentinization gradient with depth in the upper mantle. The seismic Moho limit could correspond to a serpentinization front affecting the mantle. This partially serpentinized zone constitutes a less competent level where, during subduction and exhumation, deformation and fluid circulation are localized. In this zone, the reaction kinetics are increased and the later steps of serpentinization obliterate the evidence of this progressive zone of serpentinization. In the Lanzo massif, this zone fully recrystallized into serpentinite during alpine subduction and collision. Thus, the serpentinite envelope represents the oceanic crust as defined by geophysicists, and the sharp front of serpentinization corresponds to an eclogitized seismic palaeo‐Moho.</description><identifier>ISSN: 0263-4929</identifier><identifier>EISSN: 1525-1314</identifier><identifier>DOI: 10.1111/jmg.12008</identifier><language>eng</language><publisher>Oxford, UK: Blackwell Publishing Ltd</publisher><subject>antigorite ; Earth Sciences ; Lanzo ; Lithosphere ; lizardite ; Oceanic analysis ; Petrography ; Raman ; Sciences of the Universe ; Seismology ; serpentinization front</subject><ispartof>Journal of metamorphic geology, 2013-02, Vol.31 (2), p.165-186</ispartof><rights>2012 Blackwell Publishing Ltd</rights><rights>Distributed under a Creative Commons Attribution 4.0 International License</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-a4588-942b80926a6c8d22cda383bf2c5cd52fa006a589ef6c5107fc367d1086d73a423</citedby><cites>FETCH-LOGICAL-a4588-942b80926a6c8d22cda383bf2c5cd52fa006a589ef6c5107fc367d1086d73a423</cites><orcidid>0000-0003-3097-5135 ; 0000-0003-2057-2906 ; 0000-0001-5937-3432 ; 0000-0001-8043-0905 ; 0000-0001-5475-9379</orcidid></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktopdf>$$Uhttps://onlinelibrary.wiley.com/doi/pdf/10.1111%2Fjmg.12008$$EPDF$$P50$$Gwiley$$H</linktopdf><linktohtml>$$Uhttps://onlinelibrary.wiley.com/doi/full/10.1111%2Fjmg.12008$$EHTML$$P50$$Gwiley$$H</linktohtml><link.rule.ids>230,314,780,784,885,1417,27924,27925,45574,45575</link.rule.ids><backlink>$$Uhttps://hal.science/hal-00823051$$DView record in HAL$$Hfree_for_read</backlink></links><search><creatorcontrib>DEBRET, B.</creatorcontrib><creatorcontrib>NICOLLET, C.</creatorcontrib><creatorcontrib>ANDREANI, M.</creatorcontrib><creatorcontrib>SCHWARTZ, S.</creatorcontrib><creatorcontrib>GODARD, M.</creatorcontrib><title>Three steps of serpentinization in an eclogitized oceanic serpentinization front (Lanzo Massif - Western Alps)</title><title>Journal of metamorphic geology</title><description>The Lanzo peridotite massif is a fragment of oceanic lithosphere generated in an ocean–continent transition context and eclogitized during alpine collision. Despite the subduction history, the massif has preserved its sedimentary oceanic cover, suggesting that it may have preserved its oceanic structure. It is an exceptional case for studying the evolution of a fragment of the lithosphere from its oceanization to its subduction and then exhumation. We present a field and petrological study retracing the different serpentinization episodes and their impact on the massif structure. The Lanzo massif is composed of slightly serpentinized peridotites (<20% serpentinization) surrounded by an envelope of foliated serpentinites (100% serpentinization) bordered by oceanic metabasalts and metasedimentary rocks. The limit between peridotites and serpentinites defines the front of serpentinization. This limit is sharp: it is marked by the presence of massive serpentinites (80% serpentinization) and, locally, by dykes of metagabbros and mylonitic gabbros. The deformation of these gabbros is contemporaneous with the emplacement of the magma. The presence of early lizardite in the peridotites testifies that serpentinization began during the oceanization, which is confirmed by the presence of meta‐ophicarbonates bordering the foliated serpentinite envelope. Two additional generations of serpentine occur in the ultramafic rocks. The first is a prograde antigorite that partially replaced the lizardite and the relict primary minerals of the peridotite during subduction, indicating that serpentinization is an active process at the ridge and in the subduction zone. Locally, this episode is followed by the deserpentinization of antigorite at peak P–T (estimated in eclogitized metagabbros at 2–2.5 GPa and 550–620 °C): it is marked by the crystallization of secondary olivine associated with chlorite and/or antigorite and of clinopyroxene, amphibole and chlorite assemblages. A second antigorite formed during exhumation partially to completely obliterating previous textures in the massive and foliated serpentinites. Serpentinites are an important component of the oceanic lithosphere generated in slow to ultraslow spreading settings, and in these settings, there is a serpentinization gradient with depth in the upper mantle. The seismic Moho limit could correspond to a serpentinization front affecting the mantle. This partially serpentinized zone constitutes a less competent level where, during subduction and exhumation, deformation and fluid circulation are localized. In this zone, the reaction kinetics are increased and the later steps of serpentinization obliterate the evidence of this progressive zone of serpentinization. In the Lanzo massif, this zone fully recrystallized into serpentinite during alpine subduction and collision. Thus, the serpentinite envelope represents the oceanic crust as defined by geophysicists, and the sharp front of serpentinization corresponds to an eclogitized seismic palaeo‐Moho.</description><subject>antigorite</subject><subject>Earth Sciences</subject><subject>Lanzo</subject><subject>Lithosphere</subject><subject>lizardite</subject><subject>Oceanic analysis</subject><subject>Petrography</subject><subject>Raman</subject><subject>Sciences of the Universe</subject><subject>Seismology</subject><subject>serpentinization front</subject><issn>0263-4929</issn><issn>1525-1314</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2013</creationdate><recordtype>article</recordtype><recordid>eNp1kMtKAzEUhoMoWC8L3yDgRhejuUwymWUpWpWqIIrgJsRMoqljMiZTL316o_WyEM_mwOH7fw4fAFsY7eE8-9PHuz1MEBJLYIAZYQWmuFwGA0Q4Lcqa1KtgLaUpQpgSWg6Av7yPxsDUmy7BYGEysTO-d97NVe-Ch85D5aHRbbhzvZubBgZtlHf6L2pj8D3cmSg_D_BUpeQsLOC1yeXRw2Hbpd0NsGJVm8zm114HV4cHl6OjYnI-Ph4NJ4UqmRBFXZJbgWrCFdeiIUQ3igp6a4lmumHEKoS4YqI2lmuGUWU15VWDkeBNRVVJ6DrYXfTeq1Z20T2q-CaDcvJoOJEft2yIUMTwM87s9oLtYnia5W_lNMyiz-9JTAQVvKYY_zbqGFKKxv7UYiQ_1MusXn6qz-z-gn1xrXn7H5Qnp-PvRLFIuCzr9Seh4oPkFa2YvD4bywt6I27YCZcj-g4C15Oo</recordid><startdate>201302</startdate><enddate>201302</enddate><creator>DEBRET, B.</creator><creator>NICOLLET, C.</creator><creator>ANDREANI, M.</creator><creator>SCHWARTZ, S.</creator><creator>GODARD, M.</creator><general>Blackwell Publishing Ltd</general><general>Wiley-Blackwell</general><scope>BSCLL</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>7UA</scope><scope>C1K</scope><scope>F1W</scope><scope>H96</scope><scope>L.G</scope><scope>1XC</scope><orcidid>https://orcid.org/0000-0003-3097-5135</orcidid><orcidid>https://orcid.org/0000-0003-2057-2906</orcidid><orcidid>https://orcid.org/0000-0001-5937-3432</orcidid><orcidid>https://orcid.org/0000-0001-8043-0905</orcidid><orcidid>https://orcid.org/0000-0001-5475-9379</orcidid></search><sort><creationdate>201302</creationdate><title>Three steps of serpentinization in an eclogitized oceanic serpentinization front (Lanzo Massif - Western Alps)</title><author>DEBRET, B. ; NICOLLET, C. ; ANDREANI, M. ; SCHWARTZ, S. ; GODARD, M.</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-a4588-942b80926a6c8d22cda383bf2c5cd52fa006a589ef6c5107fc367d1086d73a423</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2013</creationdate><topic>antigorite</topic><topic>Earth Sciences</topic><topic>Lanzo</topic><topic>Lithosphere</topic><topic>lizardite</topic><topic>Oceanic analysis</topic><topic>Petrography</topic><topic>Raman</topic><topic>Sciences of the Universe</topic><topic>Seismology</topic><topic>serpentinization front</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>DEBRET, B.</creatorcontrib><creatorcontrib>NICOLLET, C.</creatorcontrib><creatorcontrib>ANDREANI, M.</creatorcontrib><creatorcontrib>SCHWARTZ, S.</creatorcontrib><creatorcontrib>GODARD, M.</creatorcontrib><collection>Istex</collection><collection>CrossRef</collection><collection>Water Resources Abstracts</collection><collection>Environmental Sciences and Pollution Management</collection><collection>ASFA: Aquatic Sciences and Fisheries Abstracts</collection><collection>Aquatic Science & Fisheries Abstracts (ASFA) 2: Ocean Technology, Policy & Non-Living Resources</collection><collection>Aquatic Science & Fisheries Abstracts (ASFA) Professional</collection><collection>Hyper Article en Ligne (HAL)</collection><jtitle>Journal of metamorphic geology</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>DEBRET, B.</au><au>NICOLLET, C.</au><au>ANDREANI, M.</au><au>SCHWARTZ, S.</au><au>GODARD, M.</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Three steps of serpentinization in an eclogitized oceanic serpentinization front (Lanzo Massif - Western Alps)</atitle><jtitle>Journal of metamorphic geology</jtitle><date>2013-02</date><risdate>2013</risdate><volume>31</volume><issue>2</issue><spage>165</spage><epage>186</epage><pages>165-186</pages><issn>0263-4929</issn><eissn>1525-1314</eissn><abstract>The Lanzo peridotite massif is a fragment of oceanic lithosphere generated in an ocean–continent transition context and eclogitized during alpine collision. Despite the subduction history, the massif has preserved its sedimentary oceanic cover, suggesting that it may have preserved its oceanic structure. It is an exceptional case for studying the evolution of a fragment of the lithosphere from its oceanization to its subduction and then exhumation. We present a field and petrological study retracing the different serpentinization episodes and their impact on the massif structure. The Lanzo massif is composed of slightly serpentinized peridotites (<20% serpentinization) surrounded by an envelope of foliated serpentinites (100% serpentinization) bordered by oceanic metabasalts and metasedimentary rocks. The limit between peridotites and serpentinites defines the front of serpentinization. This limit is sharp: it is marked by the presence of massive serpentinites (80% serpentinization) and, locally, by dykes of metagabbros and mylonitic gabbros. The deformation of these gabbros is contemporaneous with the emplacement of the magma. The presence of early lizardite in the peridotites testifies that serpentinization began during the oceanization, which is confirmed by the presence of meta‐ophicarbonates bordering the foliated serpentinite envelope. Two additional generations of serpentine occur in the ultramafic rocks. The first is a prograde antigorite that partially replaced the lizardite and the relict primary minerals of the peridotite during subduction, indicating that serpentinization is an active process at the ridge and in the subduction zone. Locally, this episode is followed by the deserpentinization of antigorite at peak P–T (estimated in eclogitized metagabbros at 2–2.5 GPa and 550–620 °C): it is marked by the crystallization of secondary olivine associated with chlorite and/or antigorite and of clinopyroxene, amphibole and chlorite assemblages. A second antigorite formed during exhumation partially to completely obliterating previous textures in the massive and foliated serpentinites. Serpentinites are an important component of the oceanic lithosphere generated in slow to ultraslow spreading settings, and in these settings, there is a serpentinization gradient with depth in the upper mantle. The seismic Moho limit could correspond to a serpentinization front affecting the mantle. This partially serpentinized zone constitutes a less competent level where, during subduction and exhumation, deformation and fluid circulation are localized. In this zone, the reaction kinetics are increased and the later steps of serpentinization obliterate the evidence of this progressive zone of serpentinization. In the Lanzo massif, this zone fully recrystallized into serpentinite during alpine subduction and collision. Thus, the serpentinite envelope represents the oceanic crust as defined by geophysicists, and the sharp front of serpentinization corresponds to an eclogitized seismic palaeo‐Moho.</abstract><cop>Oxford, UK</cop><pub>Blackwell Publishing Ltd</pub><doi>10.1111/jmg.12008</doi><tpages>22</tpages><orcidid>https://orcid.org/0000-0003-3097-5135</orcidid><orcidid>https://orcid.org/0000-0003-2057-2906</orcidid><orcidid>https://orcid.org/0000-0001-5937-3432</orcidid><orcidid>https://orcid.org/0000-0001-8043-0905</orcidid><orcidid>https://orcid.org/0000-0001-5475-9379</orcidid></addata></record> |
| fulltext | fulltext |
| identifier | ISSN: 0263-4929 |
| ispartof | Journal of metamorphic geology, 2013-02, Vol.31 (2), p.165-186 |
| issn | 0263-4929 1525-1314 |
| language | eng |
| recordid | cdi_hal_primary_oai_HAL_hal_00823051v1 |
| source | Access via Wiley Online Library |
| subjects | antigorite Earth Sciences Lanzo Lithosphere lizardite Oceanic analysis Petrography Raman Sciences of the Universe Seismology serpentinization front |
| title | Three steps of serpentinization in an eclogitized oceanic serpentinization front (Lanzo Massif - Western Alps) |
| url | https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2025-01-02T01%3A21%3A51IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-proquest_hal_p&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Three%20steps%20of%20serpentinization%20in%20an%20eclogitized%20oceanic%20serpentinization%20front%20(Lanzo%20Massif%20-%20Western%20Alps)&rft.jtitle=Journal%20of%20metamorphic%20geology&rft.au=DEBRET,%20B.&rft.date=2013-02&rft.volume=31&rft.issue=2&rft.spage=165&rft.epage=186&rft.pages=165-186&rft.issn=0263-4929&rft.eissn=1525-1314&rft_id=info:doi/10.1111/jmg.12008&rft_dat=%3Cproquest_hal_p%3E2882576711%3C/proquest_hal_p%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_pqid=1283869311&rft_id=info:pmid/&rfr_iscdi=true |