Caldera Volcano

Explosive type of volcano that leaves a large circular depression. Some of these depressions can be as large as 40 kilometers in diameter. These volcanoes form when wet granitic magma quickly rises to the surface of the Earth.

Geography teacher at heart and author of http://sageography.myschoolstuff.co.za. Account Manager for http://www.campuspress.com. Passionate about South Africa!