Supervolcano
Topic: Interior of the Earth: Earthquakes, Volcanoes and the Layered Earth · NCERT: Beyond NCERT
Meaning
A supervolcano is a volcano that can throw out more than 1,000 cubic km of material in one eruption. That is the top level, VEI 8, on the Volcanic Explosivity Index (a scale of eruption size). Such a huge eruption empties the magma chamber below. The ground then collapses into it and forms a giant caldera (a large basin-shaped hollow). The ash from these eruptions can spread across whole continents.
Example
Toba in Sumatra, Indonesia, erupted about 74,000 years ago. Its ash spread far enough to reach India. Yellowstone in the USA is another supervolcano.
Don't confuse with
- Flood basalt province: also huge, but the lava pours out calmly from long cracks and builds plateaus, like the Deccan Traps. A supervolcano is violently explosive.
- Composite volcano: explosive too, but far smaller. Fuji and Vesuvius are examples.
Related concepts
- Volcano
- Magma
- Lava
- Pyroclastic material
- Active volcano
- Shield volcano
- Cinder cone
- Composite volcano
- Caldera
- Flood basalt province