Illustrated Volcano Glossary

Updated: Jul 6, 2022 07:52 GMT - Refresh

fissure vent

Volcanology
A fissure vent, also known as a volcanic fissure or simply fissure, is a linear volcanic vent through which lava erupts.
A fissure vent, also known as a volcanic fissure or simply fissure, is a linear volcanic vent through which lava erupts, usually without any explosive activity. The vent is usually a few meters wide and may be many kilometers long. Fissure vents can cause large flood basalts and lava channels. This type of volcano is usually hard to recognize from the ground and from outer space because it has no central caldera and the surface is mostly flat. The volcano can usually be seen as a crack in the ground or on the ocean floor. Narrow fissures can be filled in with lava that hardens. As erosion removes its surroundings, the lava mass could stand above the surface as a dyke. The dykes that feed fissures reach the suface from depths of a few kilometers. Fissures are usually found in or along rifts and rift zones, such as Iceland and the Great Rift Valley in Africa.

In Iceland, volcanic vents are often long fissures parallel to the rift zone where lithospheric plates are diverging. Renewed eruptions generally occur from new parallel fractures offset by a few hundred to thousands of metres from the earlier fissures. This distribution of vents and voluminous eruptions of fluid basaltic lava usually build up a thick lava plateau rather than a single volcanic edifice. The Laki fissure system produced the biggest eruption on earth in historical times, in the form of a flood basalt, during the Eldgjá eruption A.D. 934, which released 19.6 km³ (4.7 mi³) of lava.

The radial fissure vents of Hawaiian volcanoes produce “curtains of fire” as lava fountains erupt along a portion of a fissure. These vents produce low ramparts of basaltic spatter on both sides of the fissure. More isolated lava fountains along the fissure produce crater rows of small spatter and cinder cones. The fragments that form a spatter cone are hot and plastic enough to weld together, while the fragments that form a cinder cone remain separate because of their lower temperature.

Related keywords (1):

photoglossary.html
Try our free app!
Volcanoes & Earthquakes - new app for Android
Android | iOS version

More on VolcanoDiscovery

Why is there advertising on this site?
Support us - Help us upgrade our services!
We truly love working to bring you the latest volcano and earthquake data from around the world. Maintaining our website and our free apps does require, however, considerable time and resources.
We need financing to increase hard- and software capacity as well as support our editor team. We're aiming to achieve uninterrupted service wherever an earthquake or volcano eruption unfolds, and your donations can make it happen! Every donation will be highly appreciated. If you find the information useful and would like to support our team in integrating further features, write great content, and in upgrading our soft- and hardware, please make a donation (PayPal or Online credit card payment).

Planned features:
  • Improved multilanguage support
  • Tsunami alerts
  • Faster responsiveness
Thanks to your past donations, these features have been added recently:
  • Earthquake archive from 1900 onwards
  • Detailed quake stats
  • Additional seismic data sources
Download and Upgrade the Volcanoes & Earthquakes app to get one of the fastest seismic and volcano alerts online:
Android | IOS
Thank you!
Sources: VolcanoDiscovery / VolcanoAdventures and other sources as noted.
Use of material: Most text and images on our websites are owned by us. Re-use is generally not permitted without authorization. Contact us for licensing rights.
Volcanoes & Earthquakes
VolcanoDiscovery Home
Adventure & Study Travel
Tours to Volcanoes and Volcanic Areas: walking tours, photo tours, study tours Get our newsletter!
Company info
Contact | Legal info | Terms & conditions
Follow us
Follow us on facebook Follow us on Instagram Follow us on Twitter Visit our Youtube channel
EN | DE | EL | ES | FR | IT | RU
VolcanoDiscovery GmbH, Germany, Reg. nr.: HRB 103744, EU Tax Id: DE 310 395 322 owned and created by
Dr. Tom Pfeiffer, volcanologist, volcano photographer, tour organizer member of
IAVCEI
Volcanological Society
Ecotourism Greece
Insured by R+V
VolcanoDiscovery © 2004- All Rights Reserved | Privacy - cookie settings