Dike swarm

A dike swarm or dyke swarm is a large geological structure consisting of a major group of parallel, linear, or radially oriented magmatic dikes intruded within continental crust or central volcanoes in rift zones like in Iceland.[1]or other big volcanoes, (stratovolcanoes, calderas, shield volcanoes) resp. fissure systems in different parts of the world.

Magmatic dikes radiating from West Spanish Peak, Colorado, US
View of the Kattsund-Koster dyke swarm in the Koster Islands, western Sweden
Map of the Mackenzie dike swarm in Canada
Map of the Matachewan and Mistassini dike swarms in Canada
Dike swarms of Caldera de Taburiente, La Palma, Spain
Heavily altered dike swarm of the Torfajökull caldera near Landmannalaugar, Iceland

They consist of several to hundreds of dikes emplaced more or less contemporaneously during a single intrusive event, and are magmatic and stratigraphic. Such dike swarms may form a large igneous province and are the roots of volcanic province.

The occurrence of mafic dike swarms in Archean and Paleoproterozoic terrains is often cited as evidence for mantle plume activity associated with abnormally high mantle potential temperatures.

Dike swarms may extend over 400 km (250 mi) in width and length. The largest dike swarm known on Earth is the Mackenzie dike swarm in the western half of the Canadian Shield in Canada, which is more than 500 km (310 mi) wide and 3,000 km (1,900 mi) long.[2]

The number of known giant dike swarms on Earth is small, only about 25. However, the primary geometry of most giant dike swarms is poorly known due to their age and subsequent tectonic activity.

Dike swarms have also been found on Venus and Mars.[3][4]

Examples

Africa

Antarctica
  • Vestfold Hills dike swarms (East Antarctica)

Asia
  • North China dike swarm (North China craton, China)
  • Sayan dike swarm (Russia)
  • Shirotori-Hiketa dike swarm (northeastern Shikoku, Japan)

Australia
  • Gairdner dyke swarm (South Australia)
  • Mundine Well dyke swarm (Western Australia)
  • Wood's Point dyke swarm (Victoria, Australia)

Europe

Canada

Greenland

United States

South America

See also

References
  1. Re. Iceland see eg.: A. Gudmundsson: Emplacement and arrest of sheets and dykes in central volcanoes. Journal of Volcanology and Geothermal Research 116 (2002) 279^298 Retrieved 31 August 2020.
  2. "Mackenzie dike swarm". Britannica Online Encyclopedia. geological feature, Canada.
  3. Galgana, Gerald A.; Grosfils, Eric B.; McGovern, Patrick J. (2013). "Radial dike formation on Venus: Insights from models of uplift, flexure and magmatism". Icarus. 225 (1): 538–547. Bibcode:2013Icar..225..538G. doi:10.1016/j.icarus.2013.04.020.
  4. Ernst, R.E.; Grosfils, E.B.; Mège, D. (2001). "Giant Dike Swarms: Earth, Venus, and Mars". Annual Review of Earth and Planetary Sciences. 29: 489–534. Bibcode:2001AREPS..29..489E. CiteSeerX 10.1.1.473.1821. doi:10.1146/annurev.earth.29.1.489.
  5. Nkouandou, Oumarou Faarouk; Bardintzeff, Jacques-Marie; Mahamat, Oumar; Fagny Mefire, Aminatou; Ganwa, Alembert Alexandre (22 May 2017). "The dolerite dyke swarm of Mongo, Guéra Massif (Chad, Central Africa): Geological setting, petrography and geochemistry". Open Geosciences. 9 (1): 138–150. Bibcode:2017OGeo....9...12N. doi:10.1515/geo-2017-0012. ISSN 2391-5447.
  6. Puchkov, Victor; Ernst, Richard E.; Hamilton, Michael A.; Söderlund, Ulf; Sergeeva, Nina (2016). "A Devonian > 2000 km-long dolerite dyke swarm-belt and associated basalts along the Urals-Novozemelian fold-belt: part of an East-European (Baltica) LIP tracing the Tuzo Superswell". GFF. 138: 6–16. doi:10.1080/11035897.2015.1118406.
  7. Larson, E. E.; Strangway, D. W. (1 March 1969). "Magnetization of the Spanish Peaks Dike Swarm, Colorado, and Shiprock Dike, New Mexico". Journal of Geophysical Research. 74 (6): 1505–1514. Bibcode:1969JGR....74.1505L. doi:10.1029/JB074i006p01505.
  8. Druecker, M.D.; Gay, S.P., Jr., Mafic dyke swarms associated with Mesozoic rifting in eastern Paraguay, South America
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