Pyroclastic Material

This is an image of a pyroclastic flow going down the slopes of a volcano. Click on image for full size version (170K GIF) Image from: U.S. Geological Survey, photo by B. Yount

Pyroclastic material is another name for a cloud of ash, lava fragments carried through the air, and vapor. Such a flow is usually *very* hot, and moves *rapidly* under it's own power due to buoyancy provided by the vapors. Pyroclastic flows can extend miles from the volcano, and devastate life and property within their paths.

Damage from pyroclastic flows can occur by impact of rock fragments moving at high speeds or burial of the surface with ash and coarser debris a foot or more thick. Hot pyroclastic surges may start fires and kill or burn people and animals. The most devastating pyroclastic flow occured during the eruption of Mt. Pelee in 1902.

This is an image of a pyroclastic flow going down the slopes of a volcano. Click on image for full size version (170K GIF) Image from: U.S. Geological Survey, photo by B. Yount

Pyroclastic material is another name for a cloud of ash, lava fragments carried through the air, and vapor. Such a flow is usually *very* hot, and moves *rapidly* due to buoyancy provided by the vapors. Pyroclastic flows can extend miles from the volcano, and devastate life and property within their paths.

Damage from pyroclastic flows can occur by impact of rock fragments moving at high speeds or burial of the surface with ash and coarser debris a foot or more thick. Hot pyroclastic surges may start fires and kill or burn people and animals. The most devastating pyroclastic flow occured during the eruption of Mt. Pelee in 1902.

This is an image of ash flowing down the slopes of a volcano. Click on image for full size version (170K GIF) Image from: U.S. Geological Survey, photo by B. Yount

Sometimes a cloud of ash and lava fragments can be carried through the air by hot vapors from the volcano. Such a flow is usually *very* hot, and moves *rapidly* down the slopes of a volcano. Surges of flowing ash may start fires and kill or burn people and animals. The most destructive ash flow occured during the eruption of Mt. Pelee in 1902.