Geog. 110 Notes 12

Geog. 110 Notes 12 - (intermediary slope, magma type is...

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- volcanoes: -what is a volcano-vent in which lava (liquid rock, called magma underneath Earth’s surface), pyroclastic debris (solid debris from dust to boulders that is emitted by volcano), and gas erupt (when gas is involved, eruption is usually explosive) -where volcanoes occur: mid ocean ridges, rifts, convergent margins, hot spots -lava types: hotter lavas like basalt are fluid and runny (two basaltic types are aa and pahoehoe), while andesites and rhyolites are cooler and thus more viscous (slower, more solid flow) -eruption types: gentle/ continuous/ effusive (basaltic, low viscosity), explosive/ sporadic (silicic, high viscosity, much gas) -volcano types: shield volcano (magma type is basaltic, location is over a hot spot or at mid ocean ridges, more magnesium/ iron rich magma), cinder/ scoria cone (smaller, steep slopes), composite volcano
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Unformatted text preview: (intermediary slope, magma type is very silicic w/ a high viscosity, alternating layers of rock and magma, eventually central vent of volcano gets capped by material and the volcano goes dormant for a time period as magma chambers reload, location is at convergent margins), large caldera (super volcanoes, caldera is huge pit that remains when composite volcano blows its top, often a lake forms on top of caldera; an example is Yellowstone where an explosion occurred 700000 years ago, 100 times greater than Mt. St. Helens)-volcanism in Western US: caused by movement of North American plate southwest over a hot spot-volcanic hazards-lava flow, ash fall, explosive blast (powerful winds), lahars (mud flows)...
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This note was uploaded on 05/13/2011 for the course GEOG 110 taught by Professor Konrad during the Spring '08 term at UNC.

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