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Calderas. by: Jen Feigi and Kelly Foster. What is a caldera?. A caldera is a volcanic feature formed by the collapse of a volcano into itself. Calderas may be filled with water, creating crater lakes. Caldera means “cauldron” in Spanish. How do calderas form?.
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Calderas by: Jen Feigi and Kelly Foster
What is a caldera? • A caldera is a volcanic feature formed by the collapse of a volcano into itself. • Calderas may be filled with water, creating crater lakes. • Caldera means “cauldron” in Spanish.
How do calderas form? • A collapse is caused by the emptying of the magma chamber. • If enough magma is erupted, the emptied chamber will not be able to support itself. • The circular depression is the result.
Explosive Calderas • Magma rises to the surface of the volcano. • Gas quickly expands causing explosion and spreading volcanic ash. • Lava may also be erupted.
Yellowstone Caldera • Started erupting 1.9 millions years ago. • Ejected 2500 cubic kilometers of pyroclastic material. • This eruption was 2500 times bigger than the Mount Saint Helen eruption.
Non-explosive Calderas • The magma is less vicious. • These calderas are also known as subsidence calderas. • The magma chamber flows instead of exploding.
Kilauea Caldera • An active volcano in the Hawaiian Islands. • Kilauea means “spewing” or “much spreading”. • It is the most active and most visited volcano on the planet.
Non-volcanic Calderas • These calderas are very rare. • They are caused by erosion rather than eruption.
La Palma Caldera • Located in the Canary Islands. • Most active volcano in the Canary Islands. • Largest erosion crater in the world.
Reference Page • http://en.wikipedia.org/wiki/Caldera • Thompson, Graham R., Turk, Jonathan. Earth Science and the Environment. 3rd ed. Thompson: Australia 2005.