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Volcanoes
Chapter 10
Term | Definition |
---|---|
Ring of Fire | It is a long belt of volcanoes that circles much of the Pacific Ocean |
crater | Located at the summit of many volcanoes, it is a steep-walled depression |
lahar | It occurs when water-soaked volcanic ash and rock slide rapidly downhill |
vent | opening in the surface of Earth through which molten rock and gases are released |
caldera | large depression caused by either the collapse or ejection of the summit area of a volcano |
dike | when magma is injected into fractures of surrounding rock |
intraplate volcanism | activity that occurs within the plate away from plate boundaries |
shield volcano | broad, gently flowing volcano built from fluid basaltic lavas |
pluton | when magma cools and hardens beneath the surface of the Earth |
decompression melting | melting due to a drop in confining pressure that occurs as rock rises |
volcano | a mountain formed of lava and/or pyroclastic material |
lava plateau | landform produced by repeated eruptions of very fluid, basaltic lava |
hot spot | a place of significant activity or danger. |
cinder cone | a cone formed around a volcanic vent by fragments of lava thrown out during eruptions. |
sill | a tabular sheet of igneous rock intruded between and parallel with the existing strata. |
viscosity | the state of being thick, sticky, and semifluid in consistency, due to internal friction. |
composite cone | a volcanic cone composed of intermingled masses or alternate layers of lava and fragmental material |
laccolith | a mass of igneous rock, typically lens-shaped, that has been intruded between rock strata causing uplift in the shape of a dome. |
pyroclastic material | volcanic rock ejected during an eruption, including ash, bombs, and blocks |
volcanic neck | A column of igneous rock formed by congelation of lava in the conduit of a volcano and later exposed by the removal of surrounding rocks. |
batholith | a very large igneous intrusion extending deep in the earth's crust. It is exposed by erosion. |