Fine fragments (less than 2-4 mm) of volcanic rock. Volcanic ash is gritty, abrasive, and can be corrosive.
Dormant volcanoes no longer erupt. However, they might erupt again in the future.
A sudden, violent outburst, like an explosion.
Also called mudflow or debris flow, it is a mixture of water and volcanic debris that moves quickly downstream.
Molten rock that comes from a volcanic explosion and the rock that results after it has hardened and cooled.
A slow moving river of molten (liquid) rock that pours from a volcanic eruption.
Volcanic lava that has hardened after it has cooled.
Molten rock beneath the surface of the earth.
Made liquid by heat, melted.
A thick, fast-moving, and extremely hot avalanche of ash, pumice, and rock. It can move up to 50-100 mph.