The mineralogical, geochemical and isotope characteristics of alteration, mineralization and metamorphism of the Red Lake Gold Mines, Ontario
department or school: Science, Faculty of
department or school: Earth, Ocean and Atmospheric Sciences, Department of
data provider: DSpace
degree campus: UBCV
creator: Stock, Elizabeth Denise
issued: 2012-09-28T22:20:43Z
issued: 2012
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: Archean lode-gold deposits are a significant source of gold. However, exploration of this deposit type is hindered by their poorly understood genetic models and geochemical features. This project investigated the geochemical expression surrounding the Archean lode-gold Red Lake Gold Mines (RLGM) in the Superior Province, Canada. Mineral chemistry, whole rock and isotope geochemistry were used to establish how hydrothermal and metamorphic events influenced ore genesis. The RLGM is a basalt-hosted lode-gold deposit that formed from multiple superposed hydrothermal and metamorphic events. This study defined three significant superposed events which were important for gold mineralization. The first event was a widespread hybridized seafloor-magmatic event which caused reduction with FeO, MnO, K2O, SO3, SiO2, Rb, As and Cu enrichment. Seawater interaction created abundant micas-clays-chlorite-carbonate-FeMn oxides. Localized acidic magmatic fluids, in syn-volcanic faults, caused advanced argillic alteration. Subsequent peak-regional metamorphism created a widespread (>7km) occurrence of metamorphosed altered basalts. The micas-clays-chlorite-carbonate-FeMn oxides were metamorphosed to form Fe-biotite-Ti-magnetite±carbonate and Fe-chlorite-Fe-amphibole-FeMn-garnet-epidote/clinozoisite-magnetite-calcite-biotite assemblages. The metamorphosed argillic alteration created a quartz-muscovite-andalusite assemblage. Overprinting the widespread metamorphosed altered basalt was the significantly narrower (<1km), and structurally-controlled main vein and mineralization event. Abundant ankerite-calcite±quartz veins with replacement sulfide assemblages of pyrrhotite-pyrite-arsenopyrite-magnetite-gold-quartz-Mg-brown biotite were formed. The replacement ore-forming fluid enriched the basalt in CaO, MgO, SiO2, K2O, Ag, Au, Ni, Cu, Sb and Zn. Sulfides were created by sulfidation reactions between the host rock and ore-forming fluid. Redox differences during sulfidation reactions between…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/43305
note: THE MINERALOGICAL, GEOCHEMICAL AND ISOTOPE CHARACTERISTICS OF ALTERATION, MINERALIZATION AND METAMORPHISM OF THE RED LAKE GOLD MINES, ONTARIO by Elizabeth D. Stock MSci., Imperial College London, 2007 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE STUDIES (Geological Sciences) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) September 2012 © Elizabeth D. Stock, 2012 ii Abstract Archean lode-gold deposits are a significant source of gold. However, exploration of this deposit type is hindered by their poorly understood genetic models and geochemical features. This project investigated the geochemical expression surrounding the Archean lode-gold Red Lake Gold Mines (RLGM) in the Superior Province, Canada. Mineral chemistry, whole rock and isotope geochemistry were used to establish how hydrothermal and metamorphic events influenced ore genesis. The RLGM is a basalt-hosted lode-gold deposit that formed from multiple superposed hydrothermal and metamorphic events. This study defined three significant superposed events which were important for gold mineralization. The first event was a widespread hybridized seafloor-magmatic event which caused reduction with FeO, MnO, K2O, SO3, SiO2, Rb, As and Cu enrichment. Seawater interaction created abundant micas-clays-chlorite-carbonate-FeMn oxides. Localized acidic magmatic fluids, in syn-volcanic faults, caused advanced argillic alteration. Subsequent peak-regional metamorphism created a widespread (>7km) occurrence of metamorphosed altered basalts. The micas-clays-chlorite-carbonate-FeMn oxides were metamorphosed to form Fe-biotite-Ti-magnetite±carbonate and Fe-chlorite-Fe-amphibole-FeMn- garnet-epidote/clinozoisite-magnetite-calcite-biotite assemblages. The metamorphosed argillic alteration created a quartz-muscovite-andalusite assemblage. Overprinting the widespread metamorphosed altered basalt was the significantly narrower (<1km), and structurally…
has type: Thesis/Dissertation
date issued: 2012-11
is shown at: 10.14288/1.0053556
language: eng
degree discipline: Geological Sciences
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NoDerivs 3.0 Unported
rights URI: http://creativecommons.org/licenses/by-nd/3.0/
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/43305