Published:January 01, 1991
The aim of this field trip is to illustrate the geological setting and controls on gold mineralization in the Cadillac-Bousquet mining district, the major gold producing district in the Quebec Abitibi belt (Fig.1). The development of auriferous system in this area are invariably associated with major tectonic features in the volcano-sedimentary pile. The regional tour will focus on the dominant structural and stratigraphic features of the various lithological units and on the structural controls of gold mineralization. The underground tour and surface visits will allow participants to become acquainted with the complex geology of an area, that hosts several types of gold mineralization. To date, approximately 79,800 kg of gold have been extracted from over 11 orebodies on the Doyon, Bousquet and Dumagami properties (Marquis, 1990). Proven and probable gold reserves for the district are estimated to be more than 230 tonnes of gold at an average grade of 5,1 grams per tonne (Marquis, 1990).
Figures & Tables
Control on Base Metal and Gold Mineralizations, Bousquet—Rouyn-Noranda Area*
The Archean Abitibi belt is one of the largest and most studied greenstone terranes in the world. This is due not only to its precious and base meta 1 production, but also to its excellent bedrock exposure which permits observation of many Archean geological features in the south part of the belt lying between Rouyn-Noranda and Val d'Or.
The main objective of the regional field trips and the mine visits is to present the rna in stratigraphic, st ructura 1 and ore characteristics of the southern part of the Abitibi Belt. This regional field trip is scheduled to cover the Rouyn-Noranda and Cadi 11 ac-Bousquet mining camps. Operating mines will also be visited: Francoeur, Pierre-Beauchemin, Ansil, Mobrun, Doyon and Bousquet. The delegates will be able to examine the main volcanic, plutonic and sedimentary rocks as well as the various structural features in this part of the Abitibi. Ore deposits will include both massive sulphide and gold deposits. The various geological and structural environments of these deposits will also be examined.
The southern part of the Abitibi Belt in Quebec is dominated by a prominent deformation corridor, the Cadillac-Larder Lake Fault Zone. This zone is oriented E-W and separates a volcanic domain in the north from an essentially sedimentary domain in the south. This sedimentary domain, comprising clastic rocks and various granitic complexes, belongs to the Pontiac Subprovince. The volcanic domain is composed of various “blocks” of volcanic assemblages intruded by granitic masses, separated from one another by fault zones, discordances and inear sedimentary units. On the regional scale, the imbricated volcanic “blocks” are lozenge-shaped, with E-W orientd long axes. In most cases, the relationships between these volcanic and sedimentary “blocks” remain ambiguous.