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Mauna Loa, a shield volcano in Hawaii An Ancient Greek warrior's shield—its circular shape and gently sloping surface, with a central raised area, is a shape shared by many shield volcanoes. A shield volcano is a type of volcano named for its low profile, resembling a shield lying on the ground.
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 during this stage, that the low-profile "shield" shape of Hawaiian volcanoes is formed, named for the shape of a warrior's shield. [4] Eruption rates and frequencies peak, and about 95% of the volcano's eventual volume forms during a period of roughly 500,000 years. [1] The lava erupted in this stage form flows of pāhoehoe or ʻaʻā.
Formed of a complex of stratovolcanoes and shield volcanoes, [1] there are about 35 known satellite vents in the Mazama complex. [6] Mazama is surrounded by monogenetic cinder cones, lava fields, and shield volcanoes made up of calc-alkaline basalt and andesite, tholeiite, and shoshonitic andesite. Varying in age from 600,000 to 40,000 years ...
A shield is a large area of exposed Precambrian crystalline igneous and high-grade metamorphic rocks that form tectonically stable areas. [1] These rocks are older than 570 million years and sometimes date back to around 2 to 3.5 billion years.
Belknap formed on the lower slopes of Mount Washington, a highly eroded volcano, and is one of the larger mafic (rich in magnesium and iron) volcanoes in the Sisters Reach. Belknap consists of a shield volcano and pyroclastic cone and consists of basaltic and basaltic andesite lava with sub-alkaline composition, and it is characteristic of High ...
Shield volcanoes, so named for their broad, shield-like profiles, are formed by the eruption of low-viscosity basaltic or andesitic lava that can flow a great distance from a vent. They generally do not explode catastrophically but are characterized by relatively gentle effusive eruptions . [ 2 ]
[74] [26] The central shield volcano is the oldest, built mostly from 22 to 18 Ma but with a later phase from 17.5 to 13 Ma. The southern shield volcano formed from 21 to 14 Ma. The northern shield volcano was built mainly from 17 to 12 Ma. [75] These shield volcanoes erupted mostly basaltic and trachybasaltic lava flows. [26]