Near Killarney, Ontario, the Killarnean granitic intrusions are associated with recognizable Huronian formations and with a “stony porphyry”1 of questionable origin. The writer previously has described this rock as an ultra-metamorphosed quartzite, but later writers have declared that it must be of intrusive magmatic origin.
Unmistakable transitions along the strike from this porphyry into parts of the Gowganda formation have been discovered on George Lake, about 6 miles from Killarney along the general strike of rocks of disputed origin.
The contact between Huronian rocks of familiar type and those in the Huronian-Killarnean complex strikes nearly straight from Killarney toward the southeastern comer of Wanapitei Lake. The contact zone is complicated by intense shearing of intrusions within the Huronian sedimentary formations older than the main displacement, followed by widespread granitization of Huronian rocks, by igneous intrusion of very coarse porphyritic granite in large dikes within the displacement zone, and by the injection of dikes into the Huronian rocks west of the line of major disturbance. All these intrusive and transitional rocks must be distinguished from one another in relation to the various recognizable Huronian formations.
The Killarney locality is important because it shows extensive granitization and very significant rock transitions within a relatively small area.