volcanism

noun

Etymology: From French volcanisme, from volcan (“volcano”); and/or directly from volcan(o) + -ism.

1. Any of the natural phenomena and processes associated with the action of volcanos, geysers and fumaroles

   “This rejuvenation-stage or post-erosional volcanism produces lava even more alkalic than late-stage volcanism.”

   “Some 200 million years ago, the rocks that became the Palisades cliffs just across the Hudson River from Manhattan formed during volcanic activity that helped rip apart the ancient supercontinent Pangea. That volcanism helped lead to the birth of the Atlantic Ocean while it also contributed to killing off as much as a quarter of all life on Earth during the event known as the end-Triassic mass extinction.”