Our Beautiful World

Lava Dome / Kuppel


Bilde fra USGS

Lavakupler vulkantopper av størknet lava som tetter igjen
en krateråpning. De er blitt dannet av meget tregtflytende lava
(først og fremst ryolitt og dasitt).
Under kuppelen kan det bygges det opp et enormt trykk, og dette
får ofte kuppelen til å sprenges bort, og pyroklastiske skyer eller
flommer dannes.
Se f.eks. Merapi og Mt.Pelée

 
1. A steep-sided mount that forms when very viscous lava is extruded from a volcanic vent.
2. A steep-sided mound that forms when viscous lava piles up near a volcanic vent. Domes are formed by andesite, dacite, and rhyolite lavas.
3. A steep-sided mass of viscous (doughy) lava extruded from a volcanic vent, often circular in plan view and spiny, rounded, or flat on top.
Its surface is often rough and blocky as a result of fragmentation of the cooler, outer crust during growth of the dome.
Also called: Lava dome.


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ANIMALS

over 250

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BIRDS

over 500

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FLOWERS

over 225
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