An extensive zone of volcanic and seismic activity that coincides roughly with the borders of the Pacific Ocean. Name given to a belt of seismic and volcanic activity roughly surrounding the Pacific Ocean. It includes the Andes Mountains of South America, the coastal regions of western Central America and North America, the Aleutian and Kuril islands, the Kamchatka Peninsula, Japan, Taiwan, eastern Indonesia, the Philippines, New Zealand, and the island arcs of the western Pacific. About three-fourths of all historically recorded active volcanoes have occurred in this belt. See also plate tectonics