Fissure vent

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A fissure vent, also known as a volcanic 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 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. Fissure vents are usually found in or along rifts, sush as Iceland and the Great Rift Valley in Africa.

The Laki fissure system in Iceland 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.

[edit] List of Fissure vents

Name	Elevation		Location	Last eruption
	metres	feet	Coordinates
Laki	1725	5659	64.42° N 17.33° W	1783
Lanzarote	670	2198	29.03° N 13.63° W	1824
Cordon Caulle	1798	5899	40.46° N 72.25° W	1960
São Jorge	1053	3455	38.65° N 28.08° W	1907
Vatnafjöll	1235	4052	63.92° N 19.67° W	1200 BP
Quetena	5730	18799	22.25° S 67.42° W	Unknown
Nejapa Miraflores	360	1181	12.12° N 86.32° W	Unknown
Manda Inakir	600+	1968	12.38° N 42.20° E	1928
Hertali	900?	2953	9.78° N 40.33° E	Unknown
Gran Canaria	1950	6350	28.00° N 15.58° W	less than 1000 BP
Fuerteventura	529	1736	28.358° N 14.02° W	Unknown
Estelí	899	2949	13.17° N 86.40° W	Unknown
Butajiri Silti Field	2281	7484	8.05° N 83.85° E	Unknown
Bishoftu Volcanic Field	1850+	6069	8.78° N 38.98° E	Unknown
Alu	429	1407	13.82° N 40.55° E	Unknown
Singu Plateau	507	1663	22.70° N 95.98° E	Unknown
Ray Mountain	2050	-	52.23° N 120.12° W	Pleistocene

[edit] External links

• Volcanolive.com Page on Fissure Vents

[edit] See also

• Stratovolcano
• Caldera