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Volcano Term Definitions
The Spanish word for cauldron, a basin-shaped volcanic depression; by definition, at least a mile in diameter. Such large depressions are typically formed by the subsidence of volcanoes. Crater Lake occupies the best-known caldera in the Cascades.
A volcano constructed by the ejection of debris and lava flows from a central point, forming a more or less symmetrical volcano.
A volcanic cone built entirely of loose fragmented material (pyroclastics.)
A steep-walled horseshoe-shaped recess high on a mountain that is formed by glacial erosion.
The breaking of a mineral along crystallographic planes, that reflects a crystal structure.
A steep volcanic cone built by both lava flows and pyroclastic eruptions.
A passage followed by magma in a volcano.
A steep-sided, usually circular depression formed by either explosion or collapse at a volcanic vent.