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. The small monogenetic volcanoes of these fields are the most common subaerial volcanic landform.
5-659: The Uinkaret volcanic field is an area of monogenetic volcanoes in northwestern Arizona , United States , located on the north rim of the Grand Canyon . Lava flows from the Uinkaret volcanic field that have cascaded down into the Grand Canyon, damming the Colorado River , have been used to date the canyon's carving. One of these cascades is today's Lava Falls . Lava Falls Rapid , below Lava Falls on
10-803: A cosmogenic helium age of 1300 +/- 500 years BP. Pottery shards dated to between 1050 and 1200 CE were found within the lava flow, produced around the same time as the Sunset Crater eruption in the San Francisco volcanic field on the South Rim . Monogenetic volcanic field 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
15-626: 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 exceptionally large. 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
20-592: The Colorado River, is "at all water levels, the most severe rapid in Grand Canyon." The Colorado River was dammed by lava flows multiple times from 725,000 to 100,000 years ago. While some believe that these lava dams were stable, lasting up to 20,000 years and forming large reservoirs, others think they failed quickly and catastrophically as massive floods. Lava flows traveled downriver 76 miles (121 km) from river mile 178 to 254. One lava flow, from Little Springs, south of Pliocene Mount Trumbull , has
25-428: 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. The magma supplying such fields is thought to have rapidly ascended from its source region, with only short resident times (decades or less) in shallow magma chambers . This volcanology article
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