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TitreThe Archean Côté Gold intrusion-related Au(-Cu) deposit, Ontario: a large-tonnage, low-grade deposit centred on a magmatic-hydrothermal breccia
TéléchargerTéléchargement (publication entière)
AuteurKatz, L R; Kontak, D J; Dubé, B; McNicoll, V J
SourceTargeted Geoscience Initiative 4: Contributions to the understanding of Precambrian lode gold deposits and implications for exploration; par Dubé, B (éd.); Mercier-Langevin, P (éd.); Commission géologique du Canada, Dossier public 7852, 2015 p. 139-155, (Accès ouvert)
ÉditeurRessources naturelles Canada
Documentdossier public
Mediaen ligne; numérique
Référence reliéeCette publication est contenue dans Dubé, B; Mercier-Langevin, P; (2015). Targeted Geoscience Initiative 4: Contributions to the understanding of Precambrian lode gold deposits and implications for exploration, Commission géologique du Canada, Dossier public 7852
Lat/Long OENS -80.5000 -80.0000 48.0000 47.7500
SujetsArchéen; or; minéralisation; altération hydrothermale; gisements minéraux hydrothermaux; magmatisme; Ceinture de Swayze Greenstone ; géologie économique; Précambrien
Illustrationslocation maps; photographs; plots
Bibliothèque de Ressources naturelles Canada - Ottawa (Sciences de la Terre)
ProgrammeÉtude des gîtes d'or, Initiative géoscientifique ciblée (IGC-4)
Diffusé2015 06 11
Résumé(disponible en anglais seulement)
The recently discovered Côté Gold deposit, located in the southeast limb of the Swayze greenstone belt, Abitibi Subprovince, is an Archean low-grade, high-tonnage Au(-Cu) deposit. The deposit is hosted by the 2741 Ma Chester intrusive complex (CIC), a high-level, multi-phase, laccolithic-shaped synvolcanic intrusion composed of several tonalite and diorite phases. Although a close temporal and spatial relationship exists between the phases of the CIC, whole-rock geochemistry on least-altered samples suggests they are petrogenetically unrelated. Notably, the tonalite phases are characterized chemically as low-Al type, which is atypical of the tonalite-trondhjemite-granodiorite suites in the Archean Superior Province and elsewhere, but typical of primitive arc submarine environments. The mineralized system at the Côté Gold deposit is cospatial with a multi-phase, magmatic-hydrothermal breccia body that contains multiple brecciation events and matrices and is overprinted by several alteration types (biotite, sericite, silica-sodic). Whole-rock geochemistry indicates that the deposit is Au(-Cu) only and is relatively depleted in other elements (e.g. As, F, Bi, Te). The overlap of Re-Os dates on syn-gold-deposition molybdenite (2739 ± 9 Ma) with the 2741 Ma CIC is consistent with field observations that suggest an overlap of magmatic and hydrothermal events. The results of this study have defined a new significant early stage gold metallogenic event in the Abitibi Subprovince at 2740 Ma and the deposit provides a guide for future exploration in other composite, subvolcanic, low-Al intrusions in the Archean.