| Titre | Lithological and tectonic controls on banded iron formation-associated gold at the Amaruq deposit, Churchill Province, Nunavut, and implications for exploration |
| Télécharger | Téléchargements |
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| Licence | Veuillez noter que la Licence du gouvernement
ouvert - Canada remplace toutes les licences antérieures. |
| Auteur | Valette, M; De Souza, S; Mercier-Langevin, P; Côté-Mantha, O; Simard, M; Wodicka, N ; McNicoll, V J; Barbe, P |
| Source | Targeted Geoscience Initiative 5: contributions to the understanding of Canadian gold systems; par Mercier-Langevin, P (éd.); Lawley, C J M (éd.); Castonguay, S (éd.); Commission géologique du Canada, Dossier public 8712, 2020 p. 251-266, https://doi.org/10.4095/326042  Accès ouvert |
| Image |  |
| Année | 2020 |
| Éditeur | Ressources naturelles Canada |
| Document | dossier public |
| Lang. | anglais |
| DOI | https://doi.org/10.4095/326042 |
| Media | en ligne; numérique |
| Référence reliée | Cette publication est contenue dans Targeted
Geoscience Initiative 5: contributions to the understanding of Canadian gold systems |
| Référence reliée | Cette publication est reliée à Geological setting
of the 5.2 Moz Au Amaruq banded iron formation-hosted gold deposit, Churchill Province, Nunavut |
| Formats | pdf |
| Province | Nunavut |
| SNRC | 66H/07 |
| Région | Whale Lake; Mammoth Lake; Kivalliq Region |
| Lat/Long OENS | -96.7500 -96.6667 65.4333 65.3833 |
| Sujets | gisements minéraux; or; gîtes stratoïdes; gîtes de substitution; genèse des minerais; minéralisation; contrôles des minerais; établissement de modèles; prospection minière; directives d'exploration; cadre
tectonique; antécédents tectoniques; déformation; plissement; métamorphisme; faciès à schiste vert; orogenèse; cisaillement; déformation; analyses texturales; filons; sulfures; système hydrothermal; altération hydrothermale; intrusions; géologie du
substratum rocheux; lithologie; couches volcano-sédimentaires; roches sédimentaires; formations ferrifères; chailles; grauwackes; argilites; pélites; roches ignées; roches volcaniques; basaltes; komatiites; roches intrusives; diorites; roches
ultramafiques; roches mafiques; roches métamorphiques; caractéristiques structurales; plis; zones de cisaillement; failles; failles normales; analyses structurales; tendances structurelles; géométrie des plis; domaines structuraux; assemblages de
minéraux; analyses pétrographiques; roches hôtes; géochimie des roches totales; analyses par diffraction des rayons x; échantillons carrotés; graphite; silicates; Archéen; Bouclier Canadien; Province de Churchill ; Craton de Rae ; Groupe de Woodburn
Lake ; Suite de Snow Island ; Domaine de Rae ; Paléoprotérozoïque; géologie économique; tectonique; géologie structurale; pétrologie ignée et métamorphique; géochimie; Sciences et technologie; Nature et environnement; Précambrien;
Protérozoïque |
| Illustrations | cartes de localisation; cartes géolscientiques généralisées; échelles stratigraphiques; graphiques géochimiques; diagrammes ternaires; tableaux; photographies; photomicrographies; coupes
transversales |
| Programme | Initiative géoscientifique ciblée (IGC-5) Systèmes minéralisés aurifères |
| Diffusé | 2020 06 11; 2023 03 17 |
| Résumé | (disponible en anglais seulement)
The Amaruq gold deposit in Nunavut is underlain by the Neoarchean (ca. 2.73-2.63 Ga) supracrustal rocks of the Woodburn Lake group, within the Rae Craton of the
Churchill Province. The mineralized zones are hosted in polydeformed, upper greenschist-facies banded iron formation and volcanic and sedimentary rocks of the Rumble assemblage. The assemblage includes rocks of contrasting rheology and geochemistry,
such as greywacke, chert, graphitic argillite, komatiite, and komatiitic basalt, which have been deformed and metamorphosed in the Archean and during subsequent Paleoproterozoic orogenesis. In the Amaruq area, several generations of structures are
recognized: 1) tight and isoclinal F1 folds and D1 shear zones; and 2) upright and isoclinal northeast-plunging F2 folds and associated D2 shear zones that host the bulk of gold mineralization. Progressive strain accommodation during D2 deformation
led to the development of northwest-verging overthrust and recumbent F2 folds. Subsequent deformation consists of open to chevron-style, northeast- and southwest-plunging F3 folds, and north- and east-striking D4 and D5 normal faults and shear zones,
respectively. The two principal mineralized areas of the Amaruq deposit, the Whale Tail and IVR, comprise contrasting styles, geometry, and distribution of ore zones in distinct structural domains. The Whale Tail area is primarily characterized by
stratabound and locally discordant disseminated to semi-massive pyrrhotite-arsenopyrite-gersdorffite replacement-style orebodies in chert-poor silicate-facies iron formation, and by 'silica flooding' zones associated with
arsenopyrite-löllingite-pyrrhotite in chert-rich silicate-facies iron formation. The IVR area occurs in an overturned F2 fold-hinge zone and consists predominantly of shallowly southeast-dipping quartz±carbonate veins that cut the host
volcano-sedimentary sequence. Proximal alteration is characterized by variable amounts of Ca-amphibole-feldspar-epidote-muscovite-biotite-carbonate. Petrographic relationships of metamorphic and auriferous sulphide minerals indicate that prograde
upper greenschist metamorphism is coeval with D2 deformation. Native gold was in part exsolved from prograde löllingite during retrograde metamorphism to lower greenschist facies associated with D3 deformation. The crosscutting relationships between
the contrasting ore styles suggest a protracted, multiphase hydrothermal history. The age and relative timing of the gold mineralization represent key issues that are being addressed to help in the development of improved exploration models for
banded iron formation-hosted/associated gold deposits in the Churchill Province and other Archean terranes. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Le principal objectif de la phase 5 (2015-2020) du programme de l'Initiative géoscientifique ciblée (IGC) de Ressources naturelles Canada et de
la Commission géologique du Canada était de générer de nouvelles connaissances, méthodologies et modèles pour améliorer la capacité de l'industrie de l'exploration à détecter les gisements enfouis. Ce volume de synthèse contient 20 articles
individuels qui traitent des caractéristiques des gisements aurifères à l'échelle du craton à celle du gisement, ainsi que certains documents reliés au projet Gold de l'IGC-5. |
| GEOSCAN ID | 326042 |
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