Related Words

Volcanic Cone: A cone-shaped hill or mountain composed of pyroclastic debris and/or lava which builds up around a volcanic vent during eruptions.

Volcanic Breccia: A rock made up of pyroclastic fragments that are at least 64 millimeters in diameter.

Volcanic Bomb: A projectile of hot magma or rock that is blown from the vent during a volcanic eruption. These solidify in flight and frequently form an elongated rock of streamlined shape.

Volcanic Block: A pyroclastic rock fragment ranging from about fist- to car-sized.

Volcanic Ash Flow: A mixture of volcanic ash and gases that moves downhill as a density current in the atmosphere.

Volcanic Dome: A steep-sided extrusion of very viscous lava that is squeezed from a volcanic vent without major eruption. These are frequently rhyolitic in composition and produce a rounded mound above the vent.

Volcanic Pipe: A vertical or nearly vertical tunnel which connects a magma reservoir to the surface. Magma and gas travel up this tube to produce the eruption. After the eruption the tube can be filled wit . . . View Full Definition

Volcanic Neck: A vertical intrusion with the geometry of a volcanic pipe. An erosional remant of a volcanic pipe.

Volcanic Emanations: Gases, especially steam, emitted from a vent or released from lava.

Volcanic Ejecta Blanket: A collective term for all the pyroclastic rocks deposited around a volcano, especially by a volcanic explosion.