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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)
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 .
Selected geological features near the Skjaldbreiður shield volcano.(red outline). Light violet shading shows the current surface area of the Skjaldbreiður lava flows. Shading also shows: calderas, central volcanoes and fissure swarms, subglacial terrain above 1,100 m (3,600 ft), and seismically active areas. Clicking on the image enlarges to ...
[1] [3] On shield volcanoes forming from level seafloor without neighboring vents, flank rifting occurs more evenly distributed around the vent. [1] However, where the flanks of a volcano may be supported on one side by the presence of a pre-existing feature, or burdened with various planes of weakness, rift zone formation promulgates according ...
Peralkaline rhyolites erupt at relatively high temperatures of more than 1,200 °C (2,190 °F). They comprise bimodal shield volcanoes at hotspots and rifts (e.g. Rainbow Range, Ilgachuz Range and Level Mountain in British Columbia, Canada). [15] Eruptions of rhyolite lava are relatively rare compared to eruptions of less felsic lavas.
Emi Koussi seen from International Space Station. In volcanology, a pyroclastic shield or ignimbrite shield is an uncommon type of shield volcano.Unlike most shield volcanoes, pyroclastic shields are formed mostly of pyroclastic and highly explosive eruptions rather than relatively fluid basaltic lava issuing from vents or fissures on the surface of the volcano. [1]
Mount Sanford is mainly composed of andesite, and is an ancient peak, being mostly Pleistocene, although some of the upper parts of the mountain may be Holocene.The mountain first began developing 900,000 years ago, when it began growing on top of three smaller shield volcanoes that had coalesced.
The field contains at least 35 vents, arranged in a rough concentric pattern 50 kilometers (31 mi) across. The central part of the field is the most mafic, consisting of tholeiitic basalt shield volcanoes, with andesite vents further out and rhyodacite vents in the outer part of the field.