An explosive eruption is a volcanic term to describe a violent, explosive type of eruption. Mount St. Helens in 1980 was an example. Such an eruption is driven by gas accumulating under great pressure. Driven by hot rising magma, it interacts with ground water until the pressure increases to the point at which it bursts violently through the over mantle of rock. In many cases, the rising magma will contain large quantities of partially dissolved gas. Sometimes a lava plug will block the conduit to the summit, and when this occurs, eruptions are more violent. With the sudden release of pressure following the initial explosion, the gas comes out of solution violently and explosively. This secondary explosion is often far more violent than the first one; the rocks, dust, gas and pyroclastic material may be blown 20 km into the atmosphere at rate of up to 100,000 tonnes per second, traveling at several hundred metres per second. This cloud will then collapse, creating a pyroclastic flow of hot volcanic matter.
Read more about Explosive Eruption: Stages of An Explosive Eruption, Supervolcanoes
Famous quotes containing the words explosive and/or eruption:
“Anyone who has obeyed nature by transmitting a piece of gossip experiences the explosive relief that accompanies the satisfying of a primary need.”
—Primo Levi (1919–1987)
“I have done my fiddling so long under Vesuvius that I have almost forgotten to play, and can only wait for the eruption and think it long of coming. Literally no man has more wholly outlived life than I. And still it’s good fun.”
—Robert Louis Stevenson (1850–1894)