Mudflow of volcanic material is called what?

• A. Leaching
• B. Lahars
• C. Island arc
• D. Interception

Answer: (B)

Mudflows of volcanic material occur when water-saturated volcanic debris becomes a moving slurry that races down the volcano’s sides and into valleys. This phenomenon is called a lahar. Lahars can be triggered by eruption-related melting of ice and snow, heavy rainfall, or the sudden collapse of ash deposits, and they can travel rapidly, destroying anything in their path and burying communities and crops.

Leaching is a process where water dissolves soluble minerals from soil and carries them downward—not a flow of volcanic debris. An island arc is a chain of volcanic islands formed by subduction, a geological setting rather than a type of flow. Interception refers to rain being caught by vegetation before reaching the ground, part of the hydrological cycle. So the term that names the mudflow of volcanic material is lahars.