Volcanoes of the Galápagos Islands
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The Galápagos Islands are an isolated set of volcanoes, consisting of shield volcanoes and lava plateaus, located 1,200 km (746 mi) west of Ecuador. They are driven by the Galápagos hotspot, and are between 4.2 million and 700,000 years of age.[1] The largest island, Isabela, consists of six coalesced shield volcanoes, each delineated by a large summit caldera. Española, the oldest island, and Fernandina, the youngest, are also shield volcanoes, as are most of the other islands in the chain.[2][3][4] The Galápagos Islands are perched on a large lava plateau known as the Galápagos Platform, which creates a shallow-water depth of 360 to 900 m (1,181 to 2,953 ft) at the base of the islands, which stretch over a 174 mi (280 km)-long diameter.[5] Since Charles Darwin's famous visit to the islands in 1835, over 60 recorded eruptions have occurred in the islands, from six different shield volcanoes.[2][4] Of the 21 emergent volcanoes, 13 are considered active.[1]
The Galápagos are geologically young for such a big chain, and the pattern of their rift zones follows one of two trends, one north-northwest, and one east–west. The composition of the lavas of the Galápagos shields are strikingly similar to those of the Hawaiian volcanoes. Curiously, they do not form the same volcanic "line" associated with most hotspots. They are not alone in this regard; the Cobb–Eickelberg Seamount chain in the North Pacific is another example of such a delineated chain. In addition, no clear pattern of age is seen between the volcanoes, suggesting a complicated, irregular pattern of creation. How exactly the islands were formed remains a geological mystery, although several theories have been posited.[6]
Name | Last eruption |
---|---|
La Cumbre | 2024 |
Wolf | 2022 |
Sierra Negra | 2018 |
Cerro Azul | 2008 |
Alcedo | 1993 |
Marchena Island | 1991 |
Pinta Island | 1928 |
Santiago Island | 1906 |
Darwin | 1813 |
Ecuador | 1150 |
Santa Cruz Island | Unknown |
Floreana Island | Unknown |
Genovesa Island | Unknown |
San Cristóbal Island | Unknown |
Roca Redonda | Unknown |
Darwin Island | Extinct |
Wolf Island | Extinct |
Cerro Pajas | Extinct |
Española | Extinct |
Pinzon | Extinct |
Rabida | Extinct |
Santa Fe | Extinct |