Fissure vent

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A volcanic fissure and lava channel
Lava channel on Hawaii
Eruption fissure with spatter cones, Holuhraun, Iceland, 2014
Mauna Loa with different lava flows and fissure vent
File:Fagradalsfjall volcanic eruption - 2021.jpg
A volcanic fissure eruption on Fagradalsfjall, Iceland, 2021
Crater row of Laki
Eldhraun, a lava field produced by the Laki craters

A fissure vent, also known as a volcanic fissure, eruption fissure or simply a fissure, is a linear volcanic vent through which lava erupts, usually without any explosive activity. The vent is often a few metres wide and may be many kilometres long. Fissure vents can cause large flood basalts which run first in lava channels and later in lava tubes. After some time the eruption builds up spatter cones and may concentrate on one or some of them. Small fissure vents may not be easily discernible from the air, but the crater rows (see Laki) or the canyons (see Eldgjá) built up by some of them are.

The dikes that feed fissures reach the surface from depths of a few kilometers and connect them to deeper magma reservoirs, often under volcanic centers. Fissures are usually found in or along rifts and rift zones, such as Iceland and the East African Rift. Fissure vents are often part of the structure of shield volcanoes.[1]

Iceland

In Iceland, volcanic vents, which can be long fissures, often open parallel to the rift zones where the Eurasian and the North American Plate lithospheric plates are diverging, a system which is part of the Mid-Atlantic Ridge.[2] 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 sometimes voluminous eruptions of fluid basaltic lava usually builds up a thick lava plateau, rather than a single volcanic edifice. But there are also the central volcanoes, composite volcanoes, often with calderas, which have been formed during thousands of years, and eruptions with one or more magma reservoirs underneath controlling their respective fissure system.[3]

The Laki fissures, part of the Grímsvötn volcanic system, produced one of the biggest effusive eruptions on earth in historical times, in the form of a flood basalt of 12–14 km3 of lava in 1783.[4] During the Eldgjá eruption A.D. 934–40, another very big effusive fissure eruption in the volcanic system of Katla in South Iceland, ~18 km3 (4.7 mi3) of lava were released.[5] In September 2014, a fissure eruption was ongoing on the site of the 18th century lava field Holuhraun. The eruption is part of an eruption series in the Bárðarbunga volcanic system.[6]

Hawaii

The radial fissure vents of Hawaiian volcanoes also produce "curtains of fire" as lava fountains erupting along a portion of a fissure. These vents build up 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.

List of fissure vents

Name Elevation Location Last eruption
metres feet Coordinates
Bolivia Quetena 5730 18799 Lua error in package.lua at line 80: module 'strict' not found. Unknown
Canada Ray Mountain 2050 6730 Lua error in package.lua at line 80: module 'strict' not found. Pleistocene
Chile Cordón Caulle 1798 5899 Lua error in package.lua at line 80: module 'strict' not found. 2011
Eritrea Manda-Inakir 600+ 1968 Lua error in package.lua at line 80: module 'strict' not found. 1928
Ethiopia Alu 429 1407 Lua error in package.lua at line 80: module 'strict' not found. Unknown
Ethiopia Hertali 900 2953 Lua error in package.lua at line 80: module 'strict' not found. Unknown
Iceland Eldgjá 800 2625 Lua error in package.lua at line 80: module 'strict' not found. 934
Iceland Fagradalsfjall 385 1263 Lua error in package.lua at line 80: module 'strict' not found. 2021
Iceland Holuhraun 730 2395 Lua error in package.lua at line 80: module 'strict' not found. 2014
Iceland Krafla 650 2130 Lua error in package.lua at line 80: module 'strict' not found. 1984
Iceland Lakagígar (Laki) 620 2034 Lua error in package.lua at line 80: module 'strict' not found. 1784
Indonesia Banda Api 640 2100 Lua error in package.lua at line 80: module 'strict' not found. 1988
Japan Komaga-take 1996
Japan Kuchinoerabu 1980
Myanmar Singu Plateau 507 1663 Lua error in package.lua at line 80: module 'strict' not found. Unknown
Nicaragua Estelí 899 2949 Lua error in package.lua at line 80: module 'strict' not found. Unknown
Northern Mariana Islands Pagan 1981
Nicaragua Nejapa Miraflores 360 1181 Lua error in package.lua at line 80: module 'strict' not found. Unknown
Pakistan Tor Zawar[7] 2237 7339 Lua error in package.lua at line 80: module 'strict' not found. 2010
Portugal São Jorge Island 1053 3455 Lua error in package.lua at line 80: module 'strict' not found. 1907
Russia Tolbachik 1975
Spain Cumbre Vieja 1949 6394 Lua error in package.lua at line 80: module 'strict' not found. 2021
Spain Lanzarote 670 2198 Lua error in package.lua at line 80: module 'strict' not found. 1824
Sri Lanka Butajiri Silti Field 2281 7484 Lua error in package.lua at line 80: module 'strict' not found. Unknown

References

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External links

Media related to Lua error in package.lua at line 80: module 'strict' not found. at Wikimedia Commons

  1. V. Camp, Dept. of Geologic Sciences, Univ. of San Diego: How volcanoes work. Eruption types. Fissure eruptions.
  2. Lua error in package.lua at line 80: module 'strict' not found.
  3. Lua error in package.lua at line 80: module 'strict' not found.
  4. Institute of Earth Sciences, University of Iceland: Grímsvötn. Received 9/24, 2014.
  5. Institute of Earth Sciences, University of Iceland: Katla. Received 9/24, 2014.
  6. Institute of Earth Sciences, University of Iceland: Bardarbunga 2014
  7. Lua error in package.lua at line 80: module 'strict' not found.