Gold mineralization and its position in the geological evolution of the Beardmore - Tashota area

Abstract Exploration work in the Beardmore - Tashota area has led to a reinterpretation of relationships between gold mineralization and the geological evolution of the area. The host volcanic rocks form two parallel volcanic belts connected by a much smaller cross-cutting band, which trends northeast from Beardmore to Tashota. This connecting band consists of mafic and felsic volcanic, plus clastic sedimentary rocks in a sequence conformable with the contact of the Onaman Lake Batholith to the east. A metamorphic aureole or incorporated xenoliths are lacking along this major contact and the only intrusive relationship observed is chilling between mafic dikes and a cold host granite in proximity to it. Granite dikes are totally lacking in the volcanic succession, or the overlying sedimentary sequence. A major part of this sequence consists of a polymict basal conglomerate with granite boulders and volcanic clasts in a finegrained chloritic matrix. The nearest source for these boulders is the Onaman Lake batholith.
Gold mineralization in significant economic quantities (+ 50 000 ounces) occurs at the top or above the mafic volcanic succession as quartz bands. In the Northern Empire Mine, the band is conformable, folded, boudinaged and the mineral zoning shows a relationship to variations in the host rock, not structural overprinting. In general, where the host mafic tuff is medium-grained, the quartz band is thicker, up to a metre wide, and carries economic grade; where the tuff is finer-grained and bedded, the band is very thin and low grade.
Stratigraphic control and metal zoning shows that the mineralization formed as part of the development of the volcano-sedimentary succession. The other major deposits in the area (Leitch and Sturgeon River) have a similar structural history suggesting that they are also syngenetic in terms of the stratigraphic development. Regionally, these deposits were emplaced prior to any significant tectonic deformation but at the end of the mafic volcanic event.
The mafic activity was related to a period of extension which caused the volcanic troughs to develop along centres of rifting. The hiatus at the end of this event permitted extensive hydro-thermal systems to form and deposit siliceous exhalite bands within sedimentary or terminal mafic volcanic environments in promixity to major thermal sources. Subsequently, the Kenoran Orogeny deformed the entire succession into upright folds with a sub-vertical schistosity. Evidence shows that the deposits have remained intact since deposition.
Keywords: Gold mineralization, Geological evolution, Mineralization, Beardmore - Tashota area, Economic geology, Exploration.
Full Access to Technical Paper
PDF version for $20.00
Search
Sort By:  Relevance
Showing results 1 - 7
Text
Summary: The presently increasing world-wide interest in advanced ceramic materials is generally focussed on their exploitation in both structural and functional applications. With the opportunity to engineer microstructures and thereby closely control and tailor the final properties, there are many new applications being made for these materials in both areas.
The scope and some of the applications for functional ceramics are reviewed and examples of the present Canadian activity in this field are...
Publication: CIM Bulletin
Author(s): T.A. WHEAT
Keywords: Industrial minerals, Ceramics, Structural ceramics, Functional ceramics, Optical fibre, Marketing, Research and development.
Issue: 900
Volume: 80
Year: 1987
Text
Summary: Au cours de dix dernieres annees, la compagnie Maghemite a developpt, experiment^ et brevete un nouveau precede de concentration du mineral de fer a partir de la recuperation d'hematite presents au bassiii de sedimentation de la Compagnie Miniere Quebec Cartier.
A partir de cette nouvelle technologic de concentration par induction, la compagnie Maghemite produit une poudre d'hematite qui est melangee avec du strontium carbonate a un ratio de 1 a 6 en poids. Le melange homogene est achemine...
Publication: CIM Bulletin
Author(s): DENIS LANDRY
Keywords: Minereaux industriels, Poudre de ferrite, Strontium, Maghemite Inc., Compagnie Miniere Quebec Cartier.
Issue: 900
Volume: 80
Year: 1987
Text
Summary: Ontario enjoys the advantage of its proximity to the large industrial market of northeastern North America. Together with Quebec and fifteen nearby U.S. states, an industrial base of more than half the total for both countries is provided by a population of 100 million.
Mineral fillers such as barite, calcium carbonate, kaolin, mica, silica and talc are of major importance in the manufacture of paper, paint, plastics, rubber, vinyl tile, carpet backing, putty, caulks, sealants and adhesives....
Publication: CIM Bulletin
Author(s): G.ROBERT GUILLET
Keywords: Industrial minerals, Fillers, Extenders, Elastomer.
Issue: 900
Volume: 80
Year: 1987
Text
Summary: With the attainment of high temperatures it becomes possible to process any kind of material (particularly ceramics) in their liquid state. In the plasma spraying process, the material to be sprayed is rapidly heated until it is molten and is propelled by high velocity gases onto a surface where it adheres, to give protective coatings for a wide range of applications. The method could be considered as one of the most versatile and rapid to build up thick deposits (of plastics, metals,...
Publication: CIM Bulletin
Author(s): S. DALLAIRE
Keywords: Industrial minerals, Plasma spray, Protective coatings, Corrosion resistance, Coatings, Thermal barrier, Powder metallurgy technology.
Issue: 900
Volume: 80
Year: 1987
Text
Summary: Bench-scale batch milling and screening tests were carried out on secondary aluminum dross to produce an aluminum concentrate. To complement these tests, an analysis of a commercial plant was also performed by sampling dross at various stages in the plant's milling and screening circuit. These studies have indicated that benefits of increased capacity, grade and recovery of aluminum metal can be realized by addition of screens before the ball mill, longer grinding period and by grinding the...
Publication: CIM Bulletin
Author(s): K.J. FAIR, J.M. TOGURI, H.W. SMITH, D.R. FRANCIS
Keywords: Metallurgy, Aluminum dross, Milling, Grinding circuit, Comminution.
Issue: 900
Volume: 80
Year: 1987
Text
Summary: In cooperation with le Ministere de I'Energie et des ressources, Quebec, le Centre de Recherches minerales, Sainte-Foy, Quebec, and various silica producers, selected deposits of Quebec silica were identified in the southern region of the province and sampled to provide material for evaluation as glass and foundry sand by CANMET. The samples included both sandstone and quartz/quartzite. Head sample analyses ranged from 94.66% to 99.54% SiO2,  0.038% to 0.230% Fe2O3, and 0.16% to 4.51%...
Publication: CIM Bulletin
Author(s): VINCENT JOURDAIN, DENIS W. ROY, JEAN-MARC SIMARD
Keywords: Industrial minerals, Silica, Glass sand, Foundry sand, Crushing, Grinding, Magnetic separation, Flotation
Issue: 900
Volume: 80
Year: 1987
Text
Summary: In today's marketplace, heavy competition between materials is the norm. This is particularly true for the base metals, which are being increasingly challenged by new or improved materials in all traditional applications. Current usage of base metals results from a combination of a metal's intrinsic properties, and technology. The future of the base metal industry rests with innovative, high-quality product development, its ability to take advantage of the results of worldwide, massive...
Publication: CIM Bulletin
Author(s): E. GERVAIS
Keywords: Metallurgy, Zinc alloys, Zinc, Metals industry, Markets, Research and development.
Issue: 900
Volume: 80
Year: 1987
Powered by Coveo Enterprise Search