| Titre | The composition of magnetite in Archean mafic-ultramafic intrusions within the Superior Province |
| Télécharger | Téléchargements |
| |
| Licence | Veuillez noter que la Licence du gouvernement
ouvert - Canada remplace toutes les licences antérieures. |
| Auteur | Sappin, A -A ;
Houlé, M G |
| 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. 181-196, https://doi.org/10.4095/326896  Accès ouvert |
| Image |  |
| Année | 2020 |
| Éditeur | Ressources naturelles Canada |
| Document | dossier public |
| Lang. | anglais |
| DOI | https://doi.org/10.4095/326896 |
| 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 | Manitoba; Ontario; Québec |
| SNRC | 22E; 22K; 22L; 22M; 22N; 22O; 23; 24A; 24B; 24C; 24D; 24E; 24F; 24G; 24J; 24K; 24L; 24M; 24N; 25C; 25D; 25E; 25F; 31E; 31J; 31K; 31L; 31M; 31N; 31O; 32; 33; 34; 35A; 35B; 35C; 35D; 35E; 35F; 35G; 35H; 41F;
41G; 41H; 41I; 41J; 41K; 41N; 41O; 41P; 42; 43; 44; 52; 53; 54A; 54B; 54C; 54D; 62G; 62H; 62I; 62J; 62O; 62P; 63A; 63B; 63G; 63H; 63I; 63J; 63O; 63P; 64A; 64B |
| Lat/Long OENS | -100.0000 -64.0000 62.0000 45.0000 |
| Sujets | prospection minière; directives d'exploration; gisements minéraux; fer; titane; vanadium; phosphore; gîtes magmatiques; gîtes sulfureux; genèse des minerais; minéralisation; contrôles des minerais;
magnetite; pétrogenèse; géologie du substratum rocheux; lithologie; roches ignées; roches intrusives; roches mafiques; roches ultramafiques; komatiites; pyroxénites; cadre tectonique; ceintures de roche verte; magmatisme; intrusions; filons rocheux;
mise en place; gisements minéraux hydrothermaux; dynamique des fluides; cristallisation fractionnée; inclusions; exsolution; magmas; roches hôtes; associations de minéraux; géochimie des éléments en trace; géochimie des éléments en trace;
échantillons carrotés; échantillons prélevés au hasard; analyses par microsonde électronique; analyse par spectromètre de masse; Archéen; Province de Superior ; Pyroxénite de baie Chapus; Terrane de North Caribou ; Ceinture d'Abitibi Greenstone ;
géologie économique; minéralogie; géochimie; stratigraphie; Sciences et technologie; Nature et environnement; Précambrien |
| Illustrations | cartes géolscientiques généralisées; tableaux; graphiques géochimiques |
| 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 mineral chemistry of magnetite from eleven Archean mafic, mafic-ultramafic, and ultramafic intrusions within the Superior Province was determined to be used
as a petrogenetic indicator and to identify the most prospective areas for exploration of Fe-Ti-V and Fe-Ti-P mineralization. The composition of magnetite is influenced by the presence of exsolutions and inclusions (e.g. ilmenite, Al-spinel), the
type of parental melt (e.g. komatiitic, basaltic) and its Ti contents (e.g. high-Ti or low-Ti parental magmas), and the element partitioning with co-crystallized minerals (e.g. clinopyroxene) or previously crystallized minerals (e.g. chromite). The
overall composition of magnetite, however, appears to be mainly independent of the host-rock type. The composition of magnetite in compatible (e.g. Mg, Co, V, Ni, and Cr) and incompatible (e.g. Al, Ga, Mn, Ti, Zn) elements during fractionation
processes also provides useful information about the degree of differentiation of the host intrusions. Among the studied intrusions with a mafic-dominated composition, the Riviere Bell and Lac Dore complexes appear to be the most evolved, whereas the
Croal Lake, Big Mac, Butler, and Wabassi Main intrusions and the Highbank-Fishtrap intrusive complex are the most primitive. Furthermore, the variation of the minor and trace element contents of the magnetite could be used to determine the internal
stratigraphy within the mafic to ultramafic intrusions. For example, in the mafic-dominated Big Mac intrusion and in the ultramafic-dominated Baie Chapus Pyroxenite, the more vent-proximal facies appear to be located to the north and to the east,
respectively. In addition, the V and Ni+Cr contents of magnetite from the Big Mac intrusion suggest that the northern part of this intrusion is a prospective area for Fe-Ti-V mineralization, whereas the southern part has more potential for Fe-Ti-P
mineralization. In the Baie Chapus Pyroxenite, the concentrations in V and Ni+Cr in magnetite support the prospectivity of this intrusion for Fe-Ti-V mineralization. Magnetite from the oxide-bearing mafic to ultramafic rocks and the semi-massive to
massive Fe-Ti oxide layers have lower Ti+V values than expected, with magnetite compositions plotting within the fields for hydrothermal deposits in Ni/(Cr+Mn) versus Ti+V, Ca+Al+Mn versus Ti+V, and Ni+Cr versus Ti+V discrimination diagrams.
Considering that the Fe-Ti-V deposit fields in these diagrams were mostly defined based on Fe-oxides hosted within Proterozoic and Phanerozoic Fe-Ti deposits, the preliminary results presented here suggest there may be a specific signature for
magnetite from Archean Fe-Ti-V-oxide-bearing intrusions. However, further work is required to confirm this distinct signature to the Archean. |
| 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 | 326896 |
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