Get our newsletter!
Check out the volcano tours offered by Volcano-Adventures!
Volcanoes & Earthquakes - new app for Android
Guaranteed tours:
30 Jul - 13 Aug 2017: Colors of Iceland: Fire, Earth, Ice and Water - Iceland
5-18 Aug 2017: Volcano Special: Ibu - Dukono - Lokon - Halmahera (Indonesia)
23 Aug - 5 Sep 2017: Volcano Special: Ibu - Dukono - Lokon - Halmahera (Indonesia)
5-20 Sep 2017: From Krakatau to Bali - Java (Indonesia)
16-23 Sep 2017: Pearl of the Aegean - Santorini - Santorini Island, Greece
20-24 Sep 2017: Sinabung Volcano Special - Sumatra (Indonesia)
20-25 Sep 2017: Sinabung Volcano Special - Sumatra (Indonesia)
23-28 Sep 2017: Aegean's Hidden Gem: Isle of Milos - Milos Island (Greece)
1-16 Oct 2017: From Krakatau to Bali - Java (Indonesia)
13-27 Oct 2017: Volcanoes of Italy - the Grand Tour - Southern Italy
: spaces available / : guaranteed / : few spaces left / : booked out
 

Support us?


Maintaining the volcano and earthquake news sections on this website, the free Volcano Webcams tool and interactive map widget is a free-time, both time- and server cost intensive effort.
If you find the information useful and would like to support us, and help keep it alive and improve it, please consider making a small donation. Thank you!
Random pictures

Illustrated Volcano Glossary

Search for term:

explosive

Volcanology: explosive (volcanic) eruption
A small explosive eruption at Mt Etna volcano
A small explosive eruption at Mt Etna volcano
Explosion of magma at Krakatau at the beginning of a vulcanian eruption
Explosion of magma at Krakatau at the beginning of a vulcanian eruption
Explosive eruptions occur, when the erupting magma is ejected as fragments into the air, as opposed to effusive eruptions producing lava flows.
Explosive eruptions are called so, when the erupting magma is fragmented when exiting the conduit. The reason are expanding gasses from the magma itself or external water e.g. from an aquifer. The resulting fragments of the magma itself are called tephra, and consist in small and large pieces: Ash, lapilli and bombs are the typical products of explosive eruptions.

The reason for explosive eruptions are usually a high viscosity of the magma combined with high cas content. Volcanoes that often have explosive eruptions are also called "gray volcanoes", because the ash clouds they produce look gray. Most gray volcanoes are found in subduction zones, especially around the circumpacific Ring of Fire.

The opposite is effusive eruptions at the so-called "red volcanoes".

The range of explosive eruptions encompasses an incredibly large spectrum of orders of magmitude. The smalles explosive eruptions are spattering, when single lava fragments are ejected usually a few meters only from the vent. The next larger type of eruptions are lava fountains and strombolian eruptions, followed by vulcanian eruptions when a larger plug is exploded by pressurized gas-rich beneath it. The largest and most dangerous type of explosive eruptions are Plinian eruptions, which erupt several cubic kilometers of magma and produce ash columns that can reach 30-40 km of height!
 

More on VolcanoDiscovery:

Copyrights: VolcanoDiscovery and other sources as noted.
Use of material: Text and images on this webpage are copyrighted. Further reproduction and use without authorization is not consented. If you need licensing rights for photographs, for example for publications and commercial use, please contact us.