Date: June 12-16, 1991
Place: Luzon, Philippines
Result: About 350 dead (mostly from collapsed roofs); extensive damage to homes, bridges, irrigation-canal dikes, and cropland; 20 million tons of sulfur dioxide spewed into the stratosphere up to an elevation of 15.5 miles
Prior to the 1991 eruption, Pinatubo had the appearance of a steep, domelike spheroid that rose about 2,297 feet (700 meters) above a gently sloping apron made of pyroclastic and epiclastic materials. Such a volcano belongs to the class of stratocones, of which such 803 well-known exemplars as Fuji and Mayon are considerably larger than Pinatubo. The extensive pyroclastic apron of Pinatubo, however, indicated that the volcano was extremely active in prehistoric times. Until the collapse of the summit in the 1991 eruption, Pinatubo rose 5,725 feet (1,745 meters) above sea level, surrounded by older volcanic centers, including an ancestral Pinatubo due south, east, and northeast