the garibaldi volcanic belt is a north-south range of volcanoes in southwestern british columbia. it is the northern extension of the cascade volcanic arc in the united states and contains the most explosive young volcanoes in canada. it was formed by subduction of the juan de fuca plate at the cascadia subduction zone. eruption styles within the belt range from effusive to explosive, with compositions from basalt to rhyolite. the most recent major catastrophic eruption was the 2350 bp eruption of the mount meager massif. it produced an ash column at least 20 km high into the stratosphere and dammed the lillooet river with breccia.