On August 21, 1986, a sudden, catastrophic natural phenomenon occurred at Lake Nyos, a deep volcanic crater lake in northwestern Cameroon. Deep beneath the surface, years of volcanic activity had heavily saturated the water with a massive, highly pressurized concentration of carbon dioxide gas. A sudden underwater landslide triggered a limnic eruption, causing the lake to violently flip and release a massive gas bubble into the night air. The explosion shot a dense, heavy cloud of roughly one hu

Mount St. Helens Geology: Back Side of the Volcano