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TitreVariations in zircon Hf isotopes support earliest Proterozoic Wilson cycle tectonics on the Canadian Shield
AuteurPartin, C A; Sylvester, P J
SourcePrecambrian Research vol. 280, 2016 p. 457-465,
Documentpublication en série
Mediapapier; en ligne; numérique
Formatshtml; pdf
ProvinceNunavut; Territoires du Nord-Ouest; Saskatchewan; Manitoba
SNRC25; 26; 27; 35; 36; 37; 38; 446; 47; 56; 57; 64; 65; 66; 74; 75; 76; 84; 85; 86; 95; 96
Lat/Long OENS-125.0000 -56.0000 76.0000 56.0000
Sujetshafnium; isotopes; datations au zircon; datations au uranium-plomb; datations au uranium-thorium; datations au neodymium-samarium; origine; roches magmatiques; orogénies; Groupe de Penrhyn ; Craton de Rae ; Province de Churchill ; Groupe de Piling ; Groupe de Lake Harbour ; Zone de Snowbird Tectonic ; Domaine de Beaverlodge ; Orogenèse d'Arrowsmith ; géochronologie; tectonique; Protérozoïque
ProgrammeGEM2 : La géocartographie de l'énergie et des minéraux
Résumé(disponible en anglais seulement)
Sedimentary basins provide an archive of magmatic and tectonic events in their detrital zircon record, which can be dated and coupled with Hf isotopic data to reveal secular changes in the production of juvenile and evolved magmatism and track the history of orogenic events. The Rae craton, which forms a substantial portion of the northern Canadian Shield, experienced successive orogenic events along its margins during most of the Paleoproterozoic Era. Yet, some of these orogenic events are poorly defined and their details remain controversial. We present coupled detrital zircon U-Pb age and ?Hf data from Paleoproterozoic metasedimentary successions of the eastern Rae craton. The zircon preserve an archive of ~600 million yr of magmatic and tectonic history on the Rae craton and its periphery. The U-Pb and Hf isotopic data indicate that zircon provenance was dominantly from the northern and western Rae craton, where magmatic and tectonic activity was focused during the ~2.5 to 2.3 Ga Arrowsmith orogeny and the ~2.0 to ~1.93 Ga Taltson and Thelon events. Our detrital zircon dataset holds a more complete record of these Proterozoic orogenic events than is currently defined from known and dated crustal rocks on the Rae craton and shows that juvenile magmatism is more common than current models for either event suggest. Notably, an inverted U or horseshoe-shaped Hf array (?15.5 to +5.0) in our zircon dataset reflects a Wilson cycle that began in the earliest Paleoproterozoic on the Rae craton.