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TitreDepositional setting of Algoma-type banded iron formation from the Meadowbank, Meliadine, and Musselwhite gold deposits
TéléchargerTéléchargement (publication entière)
AuteurGourcerol, B; Thurston, P C; Kontak, D J; Côté-Mantha, O; Biczok, 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. 55-68, https://doi.org/10.4095/296629
Année2015
ÉditeurRessources naturelles Canada
Documentdossier public
Lang.anglais
DOIhttps://doi.org/10.4095/296629
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
Formatspdf
ProvinceOntario; Nunavut
SNRC53B/09; 53B/10; 53B/15; 53B/16; 66A/16; 66H/01; 55J/13; 55K/16; 55N/01; 55O/04
Lat/Long OENS -91.0000 -90.0000 53.0000 52.5000
Lat/Long OENS -96.5000 -96.0000 65.2500 64.7500
Lat/Long OENS -92.5000 -91.5000 63.2500 62.7500
Sujetsfer; formations ferrifères; Archéen; or; gisements minéraux; minéralisation; exploration; métallogénie; genèse des minerais; zones de failles; formation de fer d'Algoman; gîtes d'Algoman; analyses géochimiques; interprétations géochimiques; déformation; métamorphisme; terres rares; géochimie des terres rares; analyses de la roche, éléments de terres rares; milieu sédimentaire; analyses sédimentaires; géochimie; géologie économique
Illustrationslocation maps; plots; tables
Consultation
Endroit
 
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)
Algoma-type banded iron formations (BIFs) are chemical sedimentary rocks in Archean greenstone belts that comprise alternating layers of iron-rich minerals and chert and are generally interstratified with bimodal submarine volcanic rocks. However, the geological setting for Algoma-type BIF deposition remains equivocal due to the overprinting effects of post-depositional deformation and metamorphism, and the absence of modern analogues for comparative studies. Recent studies suggest the abundance of rare earth elements and yttrium (REE+Y) in chert bands may reflect the primary BIF geochemical signature and therefore may constrain geological settings favourable for BIF deposition.
In this study, the results of LA-ICP-MS analysis of chert at three BIF-hosted gold deposits are presented to assess whether epigenetic gold mineralization is preferentially developed within a particular geochemical type of BIF. Three deposits were studied: 1) the Meadowbank deposit (Churchill Province); 2) the Meliadine gold district (Churchill Province); and 3) the Musselwhite deposit (Superior Province). The results of this study, which explores REE and yttrium as tracers of depositional processes for Algoma-type BIF, suggest that chert bands record either (1) interaction of seawater with Fe-oxyhydroxides, as suggested by heavy REE enrichment coupled with La and Y enrichment; (2) high-temperature (>250oC) hydrothermal fluids, as suggested by positive Eu excursions; and/or (3) hydrogeneous contamination, which is suggested by relatively consistent REE concentrations and a chondritic Y/Ho ratio. Moreover, the pH conditions of the water column at the time of BIF deposition are evaluated using Ce/Ce* as a pH proxy, with acidic conditions associated with positive Ce/Ce* anomalies. This data set does not suggest there is a chemical preference of the studied BIF for epigenetic gold mineralization.
GEOSCAN ID296629