All About Volcanoes by

mandybarrow.com

Active volcanoA volcano that is erupting or has erupted within historical time and is considered likely to do so in the future.

AshFine particles of rock dust blown from an explosion vent.

AshfallVolcanic ash that has fallen through the air from an eruption cloud.

VentA vent is an opening at the Earth's surface of a volcanic conduit.

Composite VolcanoA steep volcanic cone built by both lava flows and pyroclastic eruptions.

Compound VolcanoA volcano that consists of a complex of two or more vents, or a volcano that has an associated volcanic dome, either in its crater or on its flanks. Examples are Vesuvius and Mont Pelee.

ConduitA passage (pipe) followed by magma in a volcano.

CraterA steep-sided, usually circular depression formed by either explosion or collapse at a volcanic vent.

Dormant volcanoA volcano which is presently inactive but which may erupt again.

EruptionThe process by which solid, liquid, and gaseous materials are ejected into the earth's atmosphere and onto the earth's surface by volcanic activity.

FaultA crack or fracture in the earth's surface.

FissuresElongated fractures or cracks on the slopes of a volcano.

GeysersSprings that throw boiling water high in the air. They are caused by volcanic heat warming trapped ground water.

Hot SpotA volcanic center, 60 to 120 miles across and persistent for at least a few tens of million of years, that is thought to be the surface expression of a persistent rising plume of hot mantle material.

LavaMagma which has reached the surface through a volcanic eruption. Streams of liquid rock that flow from a crater or fissure.

Lava FlowAn outpouring of lava onto the land surface from a vent or fissure.

MagmaMolten rock beneath the surface of the earth.Magma chamber (Magna reservoir)The subterranean cavity containing the gas-rich liquid magma which feeds a volcano.

MantleThe zone of the earth below the crust and above the core.

Ring of FireThe regions of mountain-building earthquakes and volcanoes which surround the Pacific Ocean.

StratovolcanoA volcano composed of both lava flows and pyroclastic material.

VentThe opening at the earth's surface through which volcanic materials issue forth.

Volcanic eruptionWhen hot rocks and lava burst from a volcano.

VolcanoA vent in the surface of the Earth through which magma and associated gases and ash erupt; also, the form or structure, usually conical, that is produced by the ejected material.

VulcanRoman god of fire and the forge, after whom volcanoes are named.

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