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Système D'altération Et Minéralisation En Uranium Le Long Du Faisceau Structural Kiggavik-Andrew Lake (Nunavut, Canada) : Modèle Génétique Et Guides D'exploration

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Système D'altération Et Minéralisation En Uranium Le Long Du Faisceau Structural Kiggavik-Andrew Lake (Nunavut, Canada) : Modèle Génétique Et Guides D'exploration THÈSE Pour l'obtention du grade de DOCTEUR DE L'UNIVERSITÉ DE POITIERS UFR des sciences fondamentales et appliquées Institut de chimie des milieux et matériaux de Poitiers - IC2MP (Diplôme National - Arrêté du 7 août 2006) École doctorale : Sciences pour l'environnement - Gay Lussac (La Rochelle) Secteur de recherche : Terre solide et enveloppes superficielles Présentée par : Thomas Riegler Système d'altération et minéralisation en uranium le long du faisceau structural Kiggavik-Andrew Lake (Nunavut, Canada) : modèle génétique et guides d'exploration Directeur(s) de Thèse : Daniel Beaufort Soutenue le 10 décembre 2013 devant le jury Jury : Président Alain Meunier Professeur des Universités, Université de Poitiers Rapporteur Michel Cuney Directeur de recherche CNRS, Université de Nancy 1 Rapporteur Michel Jébrak Professeur, Université du Québec à Montréal Membre Daniel Beaufort Professeur des Universités, Université de Poitiers Membre Maurice Pagel Professeur des Universités, Université Paris Sud 11, Orsay Membre David Quirt Senior Geoscientist, AREVA Resources Canada Membre Thierry Allard Directeur de recherche CNRS, Université Paris 6, Jussieu Membre Charlie Jefferson GEM uranium Project leader, Geological Survey of Canada Pour citer cette thèse : Thomas Riegler. Système d'altération et minéralisation en uranium le long du faisceau structural Kiggavik-Andrew Lake (Nunavut, Canada) : modèle génétique et guides d'exploration [En ligne]. Thèse Terre solide et enveloppes superficielles. Poitiers : Université de Poitiers, 2013. Disponible sur Internet <http://theses.univ-poitiers.fr> THESE Pour l’obtention du Grade de DOCTEUR DE L’UNIVERSITE DE POITIERS (Diplôme National - Arrêté du 7 août 2006) UFR Sciences Fondamentales et Appliquées Ecole Doctorale : Gay-Lussac Secteur de Recherche : Terre solide et enveloppes superficielles. Présentée par : Thomas Riegler ************************ Système d’altération et minéralisation en uranium le long du faisceau structural Kiggavik - Andrew Lake (Nunavut, Canada) : modèle génétique et guides d’exploration ************************ Directeur de Thèse : M. Daniel Beaufort ************************ Soutenue le 10 décembre 2013 devant la Commission d’Examen ************************ JURY Rapporteurs: MM. M. Cuney Directeur de recherche CNRS, Nancy I M. Jébrak Professeur, Université du Québec à Montréal Examinateurs: MM. M. Pagel Professeur, Université Paris Sud XI Orsay D. Quirt Senior Geoscientist, AREVA Resources Canada C. Jefferson GEM uranium Project Leader, Geological Survey of Canada T. Allard Directeur de recherche CNRS, Paris VI Jussieu A. Meunier Professeur, Université de Poitiers D. Beaufort Professeur, Université de Poitiers Remerciements Ce travail est le fruit d’une longue aventure commencée dans les prairies de la Saskatchewan, il y a de cela trois années. Je remercie donc les initiateurs de se projet : Joseph Roux, Dave Quirt, Jean-Pierre Milesi et Jean-Luc Lescuyer de m’avoir fait confiance pour mener à bien cette étude. Merci à AREVA Resources Canada, AREVA NC et ERM pour le support financier et admnistratif de cette thèse, enfin bien sur au laboratoire HydrASA pour son acceuil. Je tiens également remercier Daniel Beaufort, pour sa patience, ses conseils, et le partage de ses connaissances. Ce fût un plaisir depuis notre première rencontre à Shea Creek, et j’espère que cette relation scientifique et amicale durera après le strict cadre de cette thèse. Bien évidement je suis reconnaissant à Michel Cuney et Michel Jébrak de bien vouloir être les rapporteurs de ce travail. A Maurice Pagel, Dave Quirt, Charlie Jefferson, Thierry Allard et Alain Meunier de me faire eux aussi l’honneur de faire partie de mon jury. De manière plus particulière je voudrais remercier Thierry Allard, Mostafa Fayek et Maurice Pagel pour leur accueil dans leurs laboratoires respectifs et de leur aide au cours de ce travail. Une pensée chaleureuse pour Peter Wollenberg donc la contribution a été essentielle de par son experience et sa connaissance de la zone de Kiggavik. J’attends avec impatience le livre du récit de tes aventures arctiques ! J’aurai aussi une pensée pour mes collègues et amis, présents ou passés. De l’Université de Poitiers ou d’HydrASA ; merci Alain pour tes conseils toujours judicieux, ta disponibilité et ton humour, à mes voisins de palier Paul et Laurent, Thierry toujours là quand il faut, Abder bien sûr, et pardon pour tous les autres. Je garderai un excellent souvenir de mon passage ici. Merci également à Marion, Freddy, Mélissa, Emilie, Antoine et Jo pour votre accueil lors de mon arrivé à Poitiers. Plus récement à Fabien, Jean-Christophe, Sophie et Valentin pour leur amitié, avec une mention spéciale pour les pros de la belote et de l’ultracentrifugeuse. Un pensée aussi pour les amis de l’ESIP, Anne-Laure et Benoit ; du 504 à Orsay, Tony et Morgane ; ou ceux Dysart Road à U of M, thanks Ryan. Enfin, de Saskatoon, Dwayne, Mario, et tout particulièrement Nancy, Drew, et Rebecca. 2 Ces trois années à Poitiers ont été riches de nouvelles rencontres. La liste est trop longue, mais je ne peux pas oublier Lindsay, Mariana, Juan-Pablo, Jamal, Solweig, Camila, Chi-Wei, Blandine, Emilie, et Gabriel. Une pensée aux Gaúchos : Amanda, et sa famille ; Edson, Victória. À Christophe mon camarade depuis maintenant 10 ans. Pour le soutien dans les moments difficiles et les discussions sur la métallogénie toujours passionnante. Enfin merci à ma famille ; à Mathias, Maud, et Mathieu pour leur générosité lors de mes nombreux passages à Paris ; à ma sœur Chloé bien sûr, et tout particulièrement à mes parents pour leur soutien indéfectible depuis toujours. 3 Aussi audacieux soit-il d’explorer l’inconnu, il l’est plus encore de remettre le connu en question. Kaspar C’était un ancien basset qui, à force de travail, d’énergie, d’ambition, de volonté, de sens civique, avait réussi à devenir un saint-bernard fort correct. Pierre Dac 4 Table des matières 1. INTRODUCTION ............................................................................................................................................. 9 1.1. Introduction générale ...................................................................................................................... 9 1.2. Enjeux ............................................................................................................................................ 10 2. PRÉSENTATION DU MÉMOIRE DE THÈSE ............................................................................................................ 11 3. RAPPELS BIBLIOGRAPHIQUES .......................................................................................................................... 14 3.1. Le oulie Caadie et les assis d’âge Palopotozoiue ..................................................... 14 3.2. Les minéralisations de type discordance ....................................................................................... 19 3.3. Gitologie des ialisatios uaifes assoies au disodaes d’âge palopotozoïue 21 3.4. Contrôle structural régional et local des minéralisations .............................................................. 25 3.5. Typologie des altérations .............................................................................................................. 26 3.6. Quelques repères chronologiques : âges des minéralisations, événements thermiques (diagenèse & intrusions) et otete godaiue e lie ave les ialisatios d’uaiu de l’Athaasa et du Thelon 30 3.7. Gologie des giseets d’uaiu du distit de Kiggavik ........................................................... 32 4. RÉFÉRENCES ............................................................................................................................................... 41 5. ECHANTILLONNAGE ...................................................................................................................................... 47 A. LE SYSTEME D’ALTERATION DU FAISCEAU DE KIGGAVIK-ANDREW LAKE ET SES RELATIONS AVEC LES MINERALISATIONS EN URANIUM ................................................................................................................... 48 1. ALTERATION RELATED TO URANIUM DEPOSITS IN THE KIGGAVIK-ANDREW LAKE STRUCTURAL TREND, NUNAVUT, CANADA; NEW INSIGHTS FROM PETROGRAPHY AND CLAY MINERALOGY .......................................................................................... 49 1.1. Abstract ......................................................................................................................................... 49 1.2. Introduction ................................................................................................................................... 50 1.3. Geological setting .......................................................................................................................... 53 1.4. Sampling and analytical procedure ............................................................................................... 54 1.5. Petrography and mineralogy......................................................................................................... 57 1.6. Textural properties and crystal structure of phyllosilicates ........................................................... 63 5 1.7. Phyllosilicate crystal chemistry ...................................................................................................... 66 1.8. Discussion .....................................................................................................................................
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