Monogenetic volcanic field

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A monogenetic volcanic field is a type of volcanic field consisting of a group of small monogenetic volcanoes, each of which erupts only once, as opposed to polygenetic volcanoes, which erupt repeatedly over a period of time. Many monogenetic volcanoes are cinder cones, often with lava flows, such as Parícutin in the Michoacán-Guanajuato volcanic field, which erupted from 1943 to 1952. Some monogenetic volcanoes are small lava shields, such as Rangitoto Island in the Auckland volcanic field. Other monogenetic volcanoes are tuff rings or maars. A monogenetic field typically contains between ten and a hundred volcanoes. The Michoacán-Guanajuato field in Mexico contains more than a thousand volcanoes and is much larger than usual. [1]

Monogenetic fields occur only where the magma supply to the volcano is low or where vents are not close enough or large enough to develop plumbing systems for continuous feeding of magma. Monogenetic volcanic fields can provide snapshots of the underlying region beneath the surface, and may be useful in studying the generation of magma and the composition of the mantle since the single eruption produced would match that of the chamber from which it erupted.

Examples of monogenetic volcanic fields:

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Rangitoto Island island in New Zealand

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Nevado de Longaví mountain in Chile

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Michoacán–Guanajuato volcanic field Volcano in Mexico

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References

  1. Walker, George P. L. (2000). "Basaltic volcanoes and volcanic systems". In Sigurdsson, Haraldur (ed.). Encyclopedia of Volcanoes.