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A shield volcano is a type of volcano named for its low profile, resembling a shield lying on the ground. It is formed by the eruption of highly fluid (low viscosity ) lava , which travels farther and forms thinner flows than the more viscous lava erupted from a stratovolcano .
This list of shield volcanoes includes active, dormant and extinct shield volcanoes. Shield volcanoes are one of the three types [ specify ] of volcanoes. They have a short cone shape, and have basaltic lava which means the lava has low viscosity (viscosity is a measure of the ability for a liquid to flow)
It is a small pyroclastic shield truncated by a 2 km wide caldera filled by a crater lake. [2] It is named after Billy Mitchell, a 20th-century United States Army general who is regarded as the father of the United States Air Force. The last two major eruptions were in 1580 AD ± 20 years and about 1030 AD.
Shield volcanoes are large, slow forming volcanoes [6] that erupt fluid basaltic magma that cools to form the extrusive rock basalt. Basalt is composed of minerals readily available in the planet's crust, including feldspars and pyroxenes. [2] Fissure volcanoes pour out low viscosity basaltic magma from fissure vents to form the extrusive rock ...
Effusive basalt lava flows cool to either of two forms, ʻaʻā or pāhoehoe. [8] This type of lava flow builds shield volcanoes, which are, for example, numerous in Hawaii, [9] and is how the island was and currently is being formed.
The volcanic materials form a vertical column or plume that may rise many kilometers into the air above the vent of the volcano. In the most explosive eruptions, the eruption column may rise over 40 km (25 mi), penetrating the stratosphere. Stratospheric injection of aerosols by volcanoes is a major cause of short-term climate change.
Fears an Icelandic volcano will erupt remain high as magma spreads underground and huge cracks appear in the roads of a town most at risk.. Seismic activity in southwestern Iceland decreased in ...
Previously, up to 5,000 people living near the volcano have had to be evacuated for their safety. The volcano's recent history includes eruptions in 1966, 2005 and 2016. [ 27 ] In general, the new activity can happen anywhere on Ambae, but with highest likelihood in the rift zone, a long 2 km (1.2 mi) wide region that runs the length of the ...