The mixture of water and debris (intermediate between a volcanic avalanche and a water flood) that forms on the slopes of a volcano sometimes called a debris flow or lahar
County of Humboldt, Volcano Ash Contingency Plan to the Emergency Operations Plan, Glossary, Humboldt Operational Area, Humboldt County Sheriffs Office, Office of Emergency Services, Eureka, CA, USA 2014. http://humboldtgov.org/DocumentCenter/View/6209, (ND/ Volc Emr - Amer) {965}