Effusion (volcanism)
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Effusion (Latin: effusio, outpouring ) or effusive volcanic activity is one of the two main types of volcanic eruptions in volcanism, alongside ejection .
In contrast to explosive ejective volcanic activity, effusion is the more or less calm outflow of lava . The lava has a basaltic composition and is not very viscous due to the relative poverty of silicon dioxide . Lava fountains and curtains occur depending on the pressure and gas content in the lava ascent path. The volcanic types of the plateau volcano and the shield volcano arise during effusive activity .
Prominent examples of effusive activity are the Hawaiian volcanoes Mauna Loa , Kīlauea and Mauna Kea . In the geological past, the effusive activity of crevice volcanoes has repeatedly resulted in the occurrence of flood basalts , for example in the USA ( Columbia plateau basalt ), Siberia ( Siberian Trapp ), India ( Dekkan-Trapp ) or China ( Emeishan-Trapp ) .
See also
literature
- Dieter Richter: General Geology . 3. Edition. de Gruyter Verlag, Berlin - New York 1985, ISBN 3-11-010416-4 , pp. 255 f .