Which term matches the definition: eruptions can melt snow and ice on the summit which mixes with the ash or mud?

• A. Mudflows
• B. Pyroclastic Flow
• C. Shield Volcano
• D. Active

Answer: (A)

When heat from an eruption melts snow and ice at the summit, a lot of water mixes with volcanic ash and debris to form a dense, muddy flow that can surge down valleys. This type of flow is a mudflow—often called a lahar when it involves volcanic material and water from melted ice. Pyroclastic flows are different: they are hot clouds of ash, pumice, and gases that race along the ground, not mud formed by melted ice. The other options describe a volcano’s shape or whether it’s currently erupting, not the water-rich flow produced by ice melt.