Volcanic explosivity index
The volcanic explosivity index (commonly shortened to VEI) is a scale, from 0 to 8, for measuring the strength of eruptions. It is used by the Smithsonian Institutions Global Volcanism Program in assessing the impact of historic and prehistoric lava flows. It operates in a way similar to the Richter scale for earthquakes, in that each interval in value represents a tenfold increasing in magnitude (it is logarithmic). The vast majority of volcanic eruptions are of VEIs between 0 and 2. Magmatic eruptions
Magmatic eruptions produce juvenile clasts during explosive decompression from gas release. They range in intensity from the relatively small lava fountains on Hawaii to catastrophic Ultra-Plinian eruption columns more than 30 km (19 mi) high, bigger than the eruption of Mount Vesuvius in 79 that buried Pompeii. Hawaiian
Hawaiian eruptions are a type of volcanic eruption named after the Hawaiian volcanoes with which this eruptive type is hallmark. Hawaiian eruptions are the calmest types of volcanic events, characterized by the effusive eruption of very fluid basalt-type lavas with low gaseous content. The volume of ejected material from Hawaiian eruptions is less than half of that found in other eruptive types. Steady production of small amounts of lava builds up the large, broad form of a shield volcano.
Taal Volcano, Philippines, 1965 2020
La Soufrière of Guadeloupe (Lesser Antilles), 1975–1976 activity. Soufrière Hills volcano on Montserrat, West Indies, 1995–2012. Poás Volcano, has frequent geyser like phreatic eruptions from its crater lake. Mount Bulusan, well known for its sudden phreatic eruptions. Mount Ontake, all historical eruptions of this volcano have been phreatic including the deadly 2014 eruption. Mount Kerinci, Indonesia, produces almost annual phreatic eruptions. See also
List of volcanic eruptions in the 21st century
List of Quaternary volcanic eruptions
Prediction of volcanic activity – Research to predict volcanic activity
Timeline of volcanism on Earth

References


== Further reading ==