| Titre | Variations in the textural facies of sulphide minerals in the Eagle's Nest Ni-Cu-(PGE) deposit, McFaulds Lake greenstone belt, Superior Province, Ontario: insights from microbeam scanning energy-dispersive
X-ray fluorescence spectrometry |
| Télécharger | Téléchargements |
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| Licence | Veuillez noter que la Licence du gouvernement
ouvert - Canada remplace toutes les licences antérieures. |
| Auteur | Zuccarelli, N; Lesher, C M; Houlé, M G; Barnes, S J |
| Source | Targeted Geoscience Initiative 5: Advances in the understanding of Canadian Ni-Cu-PGE and Cr ore systems - Examples from the Midcontinent Rift, the Circum-Superior Belt, the Archean Superior Province, and
Cordilleran Alaskan-type intrusions; par Bleeker, W (éd.);
Houlé, M G (éd.); Commission géologique du Canada, Dossier public 8722, 2020 p. 165-179, https://doi.org/10.4095/326895  Accès ouvert |
| Image |  |
| Année | 2020 |
| Éditeur | Ressources naturelles Canada |
| Document | dossier public |
| Lang. | anglais |
| DOI | https://doi.org/10.4095/326895 |
| Media | en ligne; numérique |
| Référence reliée | Cette publication est contenue dans Targeted
Geoscience Initiative 5: Advances in the understanding of Canadian Ni-Cu-PGE and Cr ore systems - Examples from the Midcontinent Rift, the Circum-Superior Belt, the Archean Superior Province, and Cordilleran Alaskan-type intrusions |
| Formats | pdf |
| Province | Ontario |
| SNRC | 43C/11; 43C/12; 43C/13; 43C/14; 43D/09; 43D/10; 43D/15; 43D/16; 43E/01; 43E/02; 43E/07; 43E/08; 43F/03; 43F/04; 43F/05; 43F/06 |
| Lat/Long OENS | -87.0000 -85.0000 53.5000 52.5000 |
| Sujets | gisements minéraux; nickel; cuivre; gîtes magmatiques; gîtes sulfureux; genèse des minerais; minéralisation; contrôles des minerais; ceintures de roche verte; géologie du substratum rocheux; lithologie;
roches mafiques; roches ultramafiques; roches ignées; roches volcaniques; komatiites; roches intrusives; pyroxénites; webstérites; gabbros; roches métamorphiques; roches volcaniques métamorphosées; cadre tectonique; antécédents tectoniques;
crevasses; magmatisme; intrusions; filons rocheux; mise en place; zones de cisaillement; analyses de textures; méthodes de fluorescence aux rayons x; assemblages de minéraux; inclusions; cristallisation fractionnée; dynamique des fluides; migration
des fluides; gîtes minéralogiques; roches hôtes; faciès; Archéen; Province de Superior ; éléments du groupe de platine; géologie économique; minéralogie; géochimie; Sciences et technologie; Nature et environnement; Précambrien;
Protérozoïque |
| Illustrations | cartes de localisation; cartes géolscientiques généralisées; coupes schématiques; tableaux; photomicrographies |
| Programme | Initiative géoscientifique ciblée (IGC-5) Systèmes de nickel-cuivre-EGP-chrome |
| Diffusé | 2020 09 08; 2023 03 17 |
| Résumé | (disponible en anglais seulement)
The Eagle's Nest Ni-Cu-(PGE) deposit occurs within the 2.73 Ga Esker intrusive complex of the Ring of Fire intrusive suite, in the McFaulds Lake greenstone belt
of northern Ontario. Sulphide mineralization occurs along the northwestern margin of a subvertical ~500 m wide (north-south) x 1500 m deep komatiitic ultramafic body composed of harzburgite+/-lherzolite+/-wehrlite that is
interpreted to represent a structurally rotated, originally subhorizontal blade-shaped dyke. Disseminated (<15 wt% sulphide), net (15-35 wt% sulphide), and lesser semi-massive (50-80 wt% sulphide) and massive (>80 wt% sulphide) -textured sulphides
have been characterized using microbeam scanning energy-dispersive X-ray fluorescence spectrometry (uXRF). The images produced by this process have identified the abundances and locations of Fe, Ni, Cu, Ca, Si, and Cr within different minerals in 11
samples with representative sulphide textures: disseminated, leopard net-textured (containing bimodal coarse- and fine-grained olivine), pinto net-textured (containing bimodal coarse orthopyroxene and fine olivine), inclusion net-textured (containing
coarse inclusions of peridotite), disrupted net-textured (containing pyroxenite invading leopard and pinto net-textured sulphides), semi-massive (containing inclusions of peridotite, pyroxenite, gabbro, and net-textured sulphides), and massive. All
sulphide textures typically contain magmatic assemblages of pyrrhotite-pentlandite-chalcopyrite-magnetite+/-chromite. Notable differences include small ellipsoidal chromite inclusions only in facies with disseminated textures, little to no
clinopyroxene in leopard net-textures, abundant clinopyroxene in invasive pyroxenite in disrupted net-textures, high-Cr orthopyroxene oikocrysts in pinto net-textures, and variable degrees of segregation of Cu-rich residual sulphide liquid from
fractionally crystallizing Fe-Ni-rich monosulphide solid solution, more in disrupted and inclusion net-textures than in disseminated textures or leopard or pinto net-textures. The wide variety of net textures, the abundance of inclusions, and the
invasive pyroxenite indicate a complex history for the magmatic plumbing system. Inclusions and late-stage pyroxenitic melt may have physically facilitated migration of residual sulphide liquid from monosulphide solid solution, and the emplacement of
the late pyroxenite may have slowed cooling and/or reheated the mineralization. Many of these details are less evident visually in slabbed cores or polished thin sections, highlighting the usefulness of uXRF in interpreting the genesis and
beneficiation of texturally complex magmatic Ni-Cu-PGE ores. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Les principaux objectifs 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 étaient de générer de nouvelles connaissances, méthodologies et modèles afin d'améliorer la capacité de l'industrie de l'exploration à détecter les gisements de minerai enfouis et les extensions des systèmes de
minerai existants, et de fournir des modèles pour cibler de nouvelles zones de gisement. Ce volume synthèse contient neuf articles individuels qui traitent des principales caractéristiques des gisements magmatiques, de l'échelle du dépôt à celui du
système magmatique, à partir de divers exemples canadiens reliés au projet Ni-Cu-PGE-Cr de l'IGC-5. |
| GEOSCAN ID | 326895 |
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