supereruption

noun2

1. •
   The massive eruption of a supervolcano.

   • The Los Alamos mesa rested against the eastern slope of the Jemez Mountains, on the rime of the Valles Caldera, formed as a result of two explosive super-eruptions 1.6 and 1.1 million years ago. — 2012
2. •
   Overeruption.