2,350 years ago, is generally considered the northernmost member of the arc. A few isolated volcanic centers northwest of the Mount Meager massif such as the Silverthrone Caldera, which is a circular wide, deeply dissected caldera complex, may also be the product of Cascadia subduction because the igneous rocks andesite, basaltic andesite, dacite and rhyolite can also be found at these volcanoes as they are elsewhere along the subduction zone. At issue are the current estimates of plate configuration and rate of subduction, but based on the chemistry of these volcanoes, they are also subduction related and therefore part of the Cascade Volcanic Arc. The Cascade Volcanic Arc appears to be segmented; the central portion of the arc is the most active and the northern end least active. The Garibaldi Volcanic Belt is the northern extension of the Cascade Arc. Volcanoes within the volcanic belt are mostly stratovolcanoes along with the rest of the arc, but also include calderas, cinder cones, and small isolated lava masses. The eruption styles within the belt range from effusive to explosive, with compositions from basalt to rhyolite. Due to repeated continental and alpine glaciations, many of the volcanic deposits in the belt reflect complex interactions between magma composition, topography, and changing ice configurations. Four volcanoes within the belt appear related to seismic activity since 1975, including: Mount Meager massif, Mount Garibaldi and Mount Cayley. The Pemberton Volcanic Belt is an eroded volcanic belt north of the Garibaldi Volcanic Belt, which appears to have formed during the Miocene before fracturing of the northern end of the Juan de Fuca Plate. The Silverthrone Caldera is the only volcano within the belt that appears related to seismic activity since 1975. The Mount Meager massif is the most unstable volcanic massif in Canada. It has dumped clay and rock several meters deep into the Pemberton Valley at least three times during the past 7,300 years. Recent drilling into the Pemberton Valley bed encountered remnants of a debris flow that had traveled from the volcano shortly before it last erupted 2,350 years ago. About of rock and sand extended over the width of the valley. Two previous debris flows, about 4,450 and 7,300 years ago, sent debris at least from the volcano. Recently, the volcano has created smaller landslides about every ten years, including one in 1975 that killed four geologists near Meager Creek. The possibility of the Mount