 Mount Fee is one of the southernmost volcanoes in the Mount Cayley volcanic field.This volcanic zone forms the central portion of the larger Garibaldi Volcanic Belt, which extends from the Silverthrone Caldera in the north to the Watts Point volcano in the south.The volcanic belt has formed as a result of ongoing subduction of the Juan de Fuca Plate under the North American Plate at the Cascadia subduction zone along the British Columbia Coast.