The geochemistry of the Archean Bourlamaque batholith, Abitibi, Quebec

Abstract

The Bourlamaque batholith, of Archean age, outcrops in the Val d'Or mining camp of northwest Quebec. In order to describe its geochemistry and interpret its origin, 82 samples of the main igneous body, of synplutonic dykes, and of related later dykes were studied petrographically and analysed for 21 elements. Geochemical interpretation was based mainly on petrochemical variation (Larsen) diagrams and on abundance ratios calculated for several element pairs. The batholith is composed of at least two consanguineous and differentiated dioritic intrusions, probably introduced as sills into surrounding flat-lying volcanic rocks, and now metamorphosed to the greenschist facies. Local metamorphism appears to have been essentially isochemical except for CO2 and Cu. The redistribution of copper during metamorphism seems potentially important for mineral exploration. The Bourlamaque batholith, poor in K, Rb, Sr, Mg, Cr, and Ni, seems chemically very like the enclosing Archean volcanic rocks and similar but not identical to Phanerozoic calc-alkaline suites.

Evolution of the south-central part of the Archean Abitibi Belt, Quebec. Part I: Stratigraphy and paleogeographic model

“…13), have been recognized by Goodwin and Ridler (1970 stratigraphic subunits containing much pillow breccia, massive felsic lava, and felsic flow breccia, and minor pyroclastic intercalations are additional evidence for the existence of these complexes. The Val d'Or Complex is cored by the Bourlamaque pluton (Campiglio and Darling 1976) and by the O'Sullivan stock.…”

Late Archean regional deformation and structural controls on gold-quartz vein mineralization in the northwestern Slave Province, N.W.T., Canada

“…U-Pb ages and field relationships between the ARIC and rocks in the ARGB (Abraham et al 1994;Relf 1993;Villeneuve et al 1992) show that the ARIC was emplaced prior to the earliest deformational event, probably as a series of synvolcanic sills. This intrusive style is not uncommon in late Archean greenstone belts (e.g., the Bourlamaque Batholith (Campiglio and Darling 1976), and the Flavrian and Powell tonalite-diorite plutons (Picard 1990;Richard et al 1991)). Therefore, the evidence presented in this paper, combined with the above information, suggests that S1 foliation in the ARIC and ARGB formed during the early stages of regional shortening of the volcanoplutonic pile.…”

Facteurs de contrôle sur la mise en place des veines aurifères et la distribution de l'or à la mine Beaufor, Abitibi, Québec /

“…Le Groupe de Malartic représente une plate-forme océanique archéenne en extension associée au volcanisme de panache du manteau (Scott, 2005 (Latulippe, 1976;Imreh, 1976;Imreh 1984;Pilote et al, 2000). Campiglio (1976) et Campiglio (1977, les travaux plus récents de Imreh (1990) et de Pilote et al (2000) ont démontré qu'il s'agit en réalité d'une suite diorite -diorite quartzifère -tonalité. Le pluton de Bevcon présente une composition tonalitique et est interprété comme étant syn-à tardi-tectonique avec un âge de 2680 ± 5 (Pilote et al, 1998).…”