ABSTRACT
Two spatially and temporally related subvolcanic intrusive suites, the McDougall Brook Granitic Suite (MBG) and the Mount Pleasant Granitic Suite (MPG), occur within the Late Devonian Mount Pleasant Caldera, southwestern New Brunswick. Auriferous greisenized quartz breccias and veins are associated with the MBG, whereas Sn-W-Mo-Bi-polymetallic (Cu-Zn-Pb-In) mineralization is generically related to the slightly younger MPG. The low silica (
<70 wt. %) MBG and the high-silica (> 74 wt. %) MPG are calc-alkaline and metaluminous to weakly peraluminous (A/CNK = 0.91 - 1.28), and exhibit some crustal A-type granite affinities. However, compared to the MPG, the MBG has lower amounts of incompatible trace ...
<70% pds) et la MBG a forte teneur en silice (><70 wt. %) relative to the MPG (Si[O.sub.2]>