Which term describes a large volcano with gentle slopes?

• A. Shield Volcano
• B. Active
• C. Dormant
• D. Extinct

Answer: (A)

Volcano shape comes from how the lava erupts and how fluid it is. A shield volcano forms from low-viscosity basalt lava that can flow long distances, so it pours out over wide areas and builds a broad, gently sloping profile—more like a shield than a cone. That broad, low-angle shape characterizes these volcanoes and makes them very large in footprint but not tall and steep. Eruptions are usually effusive lava flows rather than explosive, which helps maintain those soft slopes. Classic examples are Mauna Loa and similar Hawaiian volcanoes. The other terms describe whether a volcano is currently active or likely to erupt again, not its shape, so they don’t describe the form of the mountain.