The Mid-cretaceous Rocky Ridge Formation – Important Host Rocks for Vms and Related Deposits in Central British Columbia

The recognition of remnants of large cauldron subsidence complexes along the trend of the Skeena Arch first occurred in the Tahtsa Lake area (MacIntyre, 1985). In subsequent years, evidence for other large subsidence complexes was documented in the Rocher DeBoule, Babine Mountains, Buck Creek and Babine Lake areas (MacIntyre, 2001; Church and Barakso, 1990). Originally all of these structures were believed to be Late Cretaceous in age based on the ages of nearby plutonic bodies. However, recent isotopic age-dating in the Babine Lake area suggests that the evolution of these subsidence structures began in the midCretaceous with eruption of the Rocky Ridge volcanics and that this volcanism was at least in part submarine in nature (MacIntyre, 2001).