Lahar!

LAHAR

it is a type of mudflow composed of pyroclastic material & water that flows down from a volcano, typically along a river valley, the term lahar originated in the Javanese language of Indonesia. lahars have the consistency of concrete. fluid where moving then solid when stopped. lahars are be huge, the osceola lahar produced 5600 years ago by mount rainier in washington produced a wall of mud 140 mts 450 feet deep in the white river canyon & extends over an area of over 330 square kilometers. these are extermely dangerous, became of their energy & speed. large lahares can flow several dozen meters per second & can flow for many kilometers , causing catastrophic distruction in their path. lahars possible causes :
- snow & glaciers can be melted by a pyroclastic flow during an eruption.
- a flood caused by a glacier, lake breakout & heavy rainfall can release a lahar also called glacier run. lahars are associated with volcanic activity, can occur even without any current volcanic activity , as long as the conditions are right to cause the collapse & movements of mud originating from exisitng volcanic ash deposits.