The Mount Vermilion area is located at the southeast end of the Pelly Mountains volcanic belt, about 90 km southeast of Ross River, and includes the Wolf volcanogenic massive sulphide deposit. This well exposed area was mapped at a scale of 1:25 000; several stratigraphic sections were measured across the belt. Results from this study show that the southeast end of the belt is made up of dominantly felsic volcaniclastic strata. The base of the succession consists of dominantly brown-pink lapilli tuff interbedded with argillite and lesser trachyte sills/dikes. The middle of the succession is made up primarily of heterolithic lapilli tuff with distinct argillite clasts, maroon matrix tuff with green lapilli-sized fragments and trachyte flows/sills/dikes; the upper part consists of chlorite-altered volcaniclastic rocks containing intermediate dykes and flows. The Wolf deposit is hosted within the middle portion of the volcanic succession proximal to a syenite intrusion.
To the west, towards the centre of the volcanic belt the felsic volcaniclastic component decreases as the number of sills, flows and dikes becomes more numerous, and the amount of intermediate volcanic material increases.
