| Titre | Genesis of the Island Gold Deposit, Ontario, Canada: implications for gold mineralization in the Wawa Subprovince of the Superior Province |
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| Auteur | Jellicoe, K; Ciufo, T J; Lin, S; Wodicka, N ; Wu, N; Mercier-Langevin, P; Yakymchuk, C |
| Source | Economic Geology vol. 117, no. 7, 2022 p. 1597-1612, https://doi.org/10.5382/econgeo.4963 |
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| Année | 2022 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20220457 |
| Éditeur | Society of Economic Geologists |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.5382/econgeo.4963 |
| Media | papier; numérique; en ligne |
| Formats | pdf |
| Province | Ontario |
| SNRC | 41; 42 |
| Lat/Long OENS | -88.0000 -80.0000 51.0000 44.0000 |
| Sujets | or; gisements minéraux; minéralisation; isotopes; rapports des isotopes de soufre; analyses structurales; datations au zircon; Subprovince de Wawa ; Province de Superior ; minéralogie;
géochronologie |
| Illustrations | cartes géologiques généralisées; diagrammes stéréographiques tournant de wulff; photographies; diagrammes schématiques; tableaux; graphiques; cartes géochronologiques |
| Programme | Initiative géoscientifique ciblée (IGC-6) Systèmes minéralisés |
| Diffusé | 2022 11 01 |
| Résumé | (disponible en anglais seulement)
The Island Gold deposit represents an uncommon example of known economic mineralization in the Wawa subprovince, which has been tectonically correlated with the
neighboring Abitibi subprovince that hosts worldclass orogenic gold deposits. The Island Gold deposit is hosted in dacite, gabbro, and tonalite-trondhjemite, and accompanied D2 deformation. The main ore zone dips steeply toward the south and consists
of early shear-hosted laminated quartz veins and late extensional veinlets; both vein sets host gold mineralization. A set of shallowly dipping extensional quartz veins in the Goudreau zone located north of the main ore zones also host economic gold
mineralization. Multiple sulfur isotope analysis of pyrite associated with gold-bearing alteration envelopes in the main ore zone indicates no involvement of sulfur affected by mass-independent fractionation, which rules out sulfur (± gold) sourced
from nearby banded iron formation or metasedimentary material. However, a single analysis of pyrite from an auriferous Goudreau zone vein indicates the involvement of sulfur that underwent mass-independent fractionation, which suggests a different
fluid source. Zircon U-Pb geochronology of pre- and postmineralization rock samples at Island Gold restricts the timing of mineralization to between ca. 2724 and 2672 Ma. Including previous results of detrital zircon geochronology, gold
mineralization occurred between ca. 2680 and 2672 Ma. This age range is similar to the timing of gold mineralization at the Hemlo deposit in the Wawa subprovince but is slightly older than the bulk of orogenic gold mineralization in the neighboring
southern part of the Abitibi subprovince. Multiple sulfur isotopes indicate that gold mineralization at Island Gold results from fluids of igneous affinity associated with second-generation transpressional deformation. The ore-controlling structures
were developed in bends in regional shear zones focused around relatively competent premineralization plutons. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Cette contribution présente des données (géologie structurale, géochronologie U-Pb sur zircon et analyses des isotopes multiples du soufre) pour
le gisement Island Gold situé au nord-est du lac Supérieur en Ontario. La chronologie et la source potentielle des fluides de la minéralisation aurifère sont étudiées, et des comparaisons sont faites avec le gisement Hemlo, un autre gisement aurifère
important dans la sous-province de Wawa, et avec la sous-province adjacente de l'Abitibi, bien pourvue en ressources aurifères. |
| GEOSCAN ID | 331284 |
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