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Almost all volcanoes erupt because sea water hits magma.
by hugh-avherald 5y ago
Almost all volcanoes erupt because sea water hits magma.
- ceejayoz 5y agoThis isn't true. It's not an unusual cause of explosive eruptions, but Mt. St. Helens is ~50 miles from the ocean. Magma can build up pressure entirely independently of seawater-induced steam explosions.
- yread 5y agoTo be fair that also involved a glacier
- bell-cot 5y agoIIR, the Mt. St. Helens 1980 eruption mechanism was the slow build-up of a steep slope of very weak rock, while various earthquakes (associated with deep magma movements) jiggled the whole mountain. The little glaciers on top were, at best, along for the ride when the "final" 'quake turned the unstable slope into a big landslide. Which landslide also "uncorked the champagne bottle" for the main eruption.
- Arubis 5y agoJupiter’s moon Io would disagree.