comparison, the 1980 Mount St. Helens eruption was at the lower end of VEI-5 with 1.2 km 3 , and both Mount Pinatubo in 1991 and Krakatoa in 1883 were VEI-6 with 25 km 3 . [ edit ] Known super eruptions Location of Yellowstone Hotspot in Millions of Years Ago Estimates of