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Petrochronology of Monazite and Zircon in Ultra-High Temperature Granulite from Rogaland, Norway Antonin Laurent

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Petrochronology of Monazite and Zircon in Ultra-High Temperature Granulite from Rogaland, Norway Antonin Laurent Petrochronology of monazite and zircon in ultra-high temperature granulite from Rogaland, Norway Antonin Laurent To cite this version: Antonin Laurent. Petrochronology of monazite and zircon in ultra-high temperature granulite from Rogaland, Norway. Earth Sciences. Université Paul Sabatier - Toulouse III, 2016. English. NNT : 2016TOU30290. tel-01686377 HAL Id: tel-01686377 https://tel.archives-ouvertes.fr/tel-01686377 Submitted on 17 Jan 2018 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. 5)µ4& &OWVFEFMPCUFOUJPOEV %0$503"5%&-6/*7&34*5²%&506-064& %ÏMJWSÏQBS Université Toulouse 3 Paul Sabatier (UT3 Paul Sabatier) 1SÏTFOUÏFFUTPVUFOVFQBS Antonin LAURENT le mardi 8 novembre 2016 5JUSF Étude pétrologique et chronométrique (U–Th–Pb) de la monazite et du zircon dans les granulites de ultra-haute température du Rogaland, Norvège ²DPMF EPDUPSBMF et discipline ou spécialité ED SDU2E : Sciences de la Terre et des Planètes Solides 6OJUÏEFSFDIFSDIF Géosciences Environnement Toulouse – UMR 5563 %JSFDUFVSUSJDF T EFʾÒTF Mme Stéphanie Duchene (Directrice) Mme Anne-Magali Seydoux-Guillaume (Co-directrice) M. Bernard Bingen (Co-encadrant) Jury : M. Philippe GONCALVES Maître de conférences Rapporteur M. Simon HARLEY Professeur des universités Rapporteur M. Fernando CORFU Professeur des universités Examinateur M. Jean-Marc MONTEL Professeur des universités Examinateur M. Olivier VANDERHAEGHE Professeur des universités Président du jury Mme Valérie BOSSE Maître de conférences Invitée 2 Sommaire Sommaire .............................................................................................. 3 Liste des figures .................................................................................... 8 Liste des tableaux ............................................................................... 12 Liste des annexes ................................................................................ 14 Introduction Générale ........................................................................ 15 Définitions et causes du métamorphisme de UHT ................................................................. 19 Assemblages minéralogiques et relations de phase .................................................................................. 19 Modélisation thermodynamique ............................................................................................................. 21 Les chemins P–T et leur signification géodynamique .............................................................................. 23 Durée du métamorphisme de UHT ...................................................................................................... 24 Lier le temps à la température dans les granulites ................................................................... 25 La mesure du temps dans les granulites .................................................................................... 27 Principe de la géochronologie .................................................................................................................. 27 Comportement du zircon et de la monazite ............................................................................................ 29 Enjeux pour les ressources naturelles stratégiques .................................................................. 31 Problématique et plan de l’étude ................................................................................................ 32 Références ..................................................................................................................................... 33 Chapitre 1 ............................................................................................ 47 Overview of the Sveconorwegian orogeny and Mesoproterozoic evolution of Rogaland, S-Norway ......................................................... 47 Résumé ........................................................................................................................................... 49 Framework of Rodinia assembly ................................................................................................ 51 The Sveconorwegian orogeny .................................................................................................... 52 1280–1150 Ma time interval (pre-Sveconorwegian) ............................................................................. 53 1150–1080 Ma time interval (Arendal phase) .................................................................................... 54 1050–1030 Ma time interval (Agder phase) ....................................................................................... 55 1030–1000 Ma time interval (Agder phase) ....................................................................................... 56 990–970 Ma time interval (Falkenberg phase) .................................................................................... 57 970–950 Ma time interval (Dalane phase) .......................................................................................... 57 950–920 Ma time interval (Dalane phase) .......................................................................................... 58 Tectono-magmatic evolution of Rogaland ............................................................................... 59 Magmatism .......................................................................................................................................... 59 Metamorphism ..................................................................................................................................... 62 References ..................................................................................................................................... 64 Tables ............................................................................................................................................. 70 3 Chapitre 2 ........................................................................................... 73 Sulphate incorporation in monazite lattice and dating the cycle of sulphur in metamorphic belts ............................................................... 73 Résumé ........................................................................................................................................... 75 Abstract .......................................................................................................................................... 76 Introduction .................................................................................................................................. 77 Monazite crystal chemistry .......................................................................................................... 78 Geological background ................................................................................................................ 79 Analytical methods ....................................................................................................................... 79 Monazite zoning and micro-chemistry .................................................................................................... 79 Monazite U–Th–Pb geochronology ....................................................................................................... 82 Transmission electron microscopic (TEM) imaging ................................................................................ 83 Results ............................................................................................................................................ 84 Sample petrology ................................................................................................................................... 84 Monazite texture, composition and inclusions ........................................................................................ 85 Nano-characterization of monazite by TEM ......................................................................................... 90 U–Th–Pb geochronology ....................................................................................................................... 90 Discussion ...................................................................................................................................... 94 Mechanism of S incorporation in monazite ............................................................................................ 94 Significance of S-rich monazite .............................................................................................................. 95 Metasomatic replacement of S-rich monazite .......................................................................................... 96 Dating S mobility in metamorphic belts ................................................................................................. 98 Conclusion ..................................................................................................................................... 99 Acknowledgement .....................................................................................................................
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