Global Volcanism Program

Volcanoes of the World

Volcanoes of the Atlantic Ocean

	Northern Atlantic Ocean
	Azores
	Canary Islands
	Cape Verde Islands
	Central and Southern Atlantic Ocean

Regional Volcanology Highlights from Simkin and Siebert, 1994.

Known eruptions from this large region total 117—only Antarctica has less—but its historical record is relatively long. The largest island group, the Canaries, is reached by favorable winds from Europe and was an important base for early voyages to the new world. In fact, Christopher Columbus recorded a 1492 eruption on Tenerife, just seven weeks before that same logbook carried documentation of a more historic observation. The Azores were also well placed for sailors because of the predominant westerly winds used for return routes to Europe.

The Canaries were mentioned by Pliny around 40 BC, and were often rediscovered in the following centuries. They were claimed by Portugal in 1341, the year of the region's first historical eruption (a somewhat questionable report of activity somewhere on Tenerife), but were awarded to Spain by the Pope 3 years later. They were settled in 1402 and conquest of the indigenous Guanches population was complete by 1496. The Canaries now have the largest population (1.6 million) in the region and, as part of Spain, claim Pico de Teide as that nation's highest point.

A discovery date for the Azores is uncertain, but they appear on a map from 1351 AD. The Portuguese visited in 1427-31 and colonization began in 1445, a year after the first historical eruption. The nine islands now support about 250,000 people, half of them on the island of Sao Miguel.

The Cape Verde islands were discovered by Portugal in 1456 and settled 6 years later. An eruption beginning in 1500 appears to have continued for about 260 years, with behavior similar to that of Italy's Stromboli. Independence from Portugal came in 1975.

Tristan de Cunha was discovered by the Portuguese in 1506 and the islands were much visited by whalers and sealers. They were first inhabited by St. Helenans in the 19th century and annexed by Britain in 1816. The residents were evacuated during the 1961 eruption, but most elected to return within two years and the 1970 population was estimated at 280.

Aside from submarine activity (most of it uncertain) the only other dated eruption in the region is from Norway's Bouvet Island, the most remote in the world. It was discovered in 1739, but its only known eruption was 2,000 years ago (by magnetic dating).

Volcanism in the region is largely caused by hotspots in oceanic crust, and the region has the highest proportion of fissure vent volcanoes (as primary features). Several known volcanoes lie along or near the Mid-Atlantic Ridge that separates the Eurasian and African plates from the North and South American plates, but the Canaries and Cape Verdes lie just west of the African continental margin.