Volcán Wolf

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Volcán Wolf

Volcán Wolf, 2001, NASA Landsat 7 image
Elevation 1,707 m (5,600 ft)
Prominence 1,707 m (5,600 ft)
Listing Ultra
Location
Volcán Wolf
Galápagos Islands
Location Isabela Island, Galapagos Islands
Coordinates 0°02′00″N 91°20′00″W / 0.033333°N 91.333333°W / 0.033333; -91.333333Coordinates: 0°02′00″N 91°20′00″W / 0.033333°N 91.333333°W / 0.033333; -91.333333
Geology
Type Shield Volcano

Volcán Wolf is the highest peak in the Galapagos Islands and is situated on Isabela Island and reaches 1,707 m (5,600 ft). It is a shield volcano with a characteristic upturned soup bowl shape.

The volcano was named after Theodor Wolf a German geologist who studied the Galapagos Islands in the 19th century, Wolf Island in the north of the Galapagos is also named after him.

Its height makes Wolf Volcano an "ultra prominent peak", which is a peak with a topographic prominence of over 1500m.[1]

Geology

The Galapagos Islands are believed to be formed from a mantle plume, which creates a hotspot of volcanic activity away from plate boundaries where islands then form, similar to the process that created the Hawaiian islands. This plume stays in place while the Nazca plate moves above it; the relative movement of this plate is 91 degrees.[2] The oceanic plate under Wolf Volcano is believed to be only 10 million years old., and the volcano is estimated to be less than half a million years old.[3]

Wolf is situated at the northern end of Isabela Island in the Galapagos, and sits on the Equator. It is one of the six coalescing volcanoes that make up this island, the others being Ecuador, Darwin, Alcedo, Sierra Negra, and Cerro Azul. Along with the Fernandina Island volcano, the western Galapagos volcanoes have similar structures that differ from the volcanoes in the eastern part of the archipelago. The western volcanoes are higher and have larger calderas than those to the east, they are also shaped like an upturned soup bowl.

Wolf reaches a height of over 1700 metres; the caldera is 6 by 7 km and has a depth of 700m. Only Cerro Azul has a caldera of similar depth in the Galapagos. Following the last eruption, there was collapse in the caldera, causing its stepped appearance. Wolf has very steep slopes reaching 35 degrees in places, making access difficult. The first historical eruption in the Galapagos was recorded for this volcano in 1797; a further nine eruptions have been recorded since then, the last being in 1982. Eruptions prior to 1797 have been dated from analysis of surface exposures. The newest lavas are on the eastern and southern sides as well as within the caldera.[4][5]

Lava flows from Wolf are unusual for a mid-ocean island and also differ from the two volcanoes next to it, Ecuador and Darwin and other volcanoes closer to the centre of the plume. The lavas from Wolf are similar to those erupted from the Galapagos Spreading Center, a mid-ocean ridge over 200 km away. This is believed to be due to interaction between the plume, which is centred on Fernandina, and the upper mantle.[2]

Wildlife

As is common in the Galapagos, Wolf Volcano has unique fauna, differing not only from the other islands in the group but also from its neighbouring volcanoes on the same island. It has its own subspecies of Galapagos tortoise, Chelonoidis nigra becki [6] which has a saddleback shell and is found on the northern and western slopes of the volcano,[7] away from the more recent lava flows where there is denser vegetation. However, tortoise subspecies from many different Galapagos islands have been abandoned at Wolf Volcano by ships which at one time collected the tortoise as a food source. C. n. becki is threatened due to population pressures such as predation by feral cats.[8] During a 2008 survey of over 1600 specimens on Wolf Volcano all morphologies of tortoise were found, including two that in shape are similar to Lonesome George. DNA studies of these specimens are currently being undertaken.[9][10]

In 2009 it was announced that a new species of land iguana had been found on the slopes of Wolf Volcano.[11] The pink land iguana had been found by park rangers in 1986 and has been studied by scientists since 2000. Scientists are unsure where the species developed as it is believed to have separated from the other land iguana of Galapagos prior to Wolf volcano or Isabela Island having formed.

Ecology

The natural habitat is under threat from the introduction of goats. The Galapagos National Park has instigated Project Isabela to eradicate feral goats from around Wolf.[12]

See also

References

  1. de Ferranti, Jonathan; Maizlish, Aaron (2005). "Ecuador: 15 Mountain Summits with Prominence of 1,500 meters or greater". peaklist.org. Retrieved June 17, 2013. 
  2. 2.0 2.1 Geist, Dennis J.; Naumann, Terry R.; Standish, Jared J.; Kurz, Mark D.; Harpp, Karen S.; White, William M.; Fornari, Daniel J. (June 13, 2005). "Wolf Volcano, Galápagos Archipelago: Melting and Magmatic Evolution at the Margins of a Mantle Plume". Journal of Petrology (Oxford University Press) 46 (11): 2197–2224. doi:10.1093/petrology/egi052. Retrieved June 18, 2013. 
  3. Scott, Michon; Allen, J. (February 13, 2009). "Wolf Volcano, Galapagos Islands". Earth Observatory: Images. EOS Project Science Office, NASA Godard Space Flight Center. Retrieved June 18, 2013. 
  4. "Volcan Wolf". Galapagos Geology on the Web. Cornell University Department of Geological Sciences. Retrieved June 18, 2013. 
  5. "Wolf". Global Volcanism Program, Smithsonian Institution. http://www.volcano.si.edu/world/volcano.cfm?vnum=1503-02%3D.
  6. Rothman, Robert H. "Giant Tortoise". Reptiles. Rochester Institute of Technology. Retrieved June 18, 2013. 
  7. Swingland, Ian R.; Klemens, Michael W.; The Durrell Institute of Conservation and Ecology, eds. (1989), "The Conservation Biology of Tortoises", Occasional Papers of the IUCN Species Survival Commission (SSC) No. 5, Switzerland: International Union for Conservation of Nature and Natural Resources, pp. 24–28, ISBN 2880329868, retrieved June 17, 2013 
  8. "Tortoise & Freshwater Turtle Specialist Group. Chelonoidis nigra spp. becki". IUCN 2012. IUCN Red List of Threatened Species. Version 2012.2. International Union for Conservation of Nature and Natural Resources. 1996. Retrieved June 17, 2013. 
  9. Emanuel, Janet Rettig (May 11, 2007). "Study of Galápagos tortoises’ DNA may locate mate for 'Lonesome George'". Yale Bulletin & Calendar (Yale University) 35 (28). Retrieved June 18, 2013. 
  10. Galpagos Conservancy
  11. Black, Richard (January 5, 2009), "Pink iguana rewrites family tree", BBC News, retrieved June 18, 2013 
  12. "Ecosystem Restoration: Project Isabela". Galapagos Conservancy: Conservation: Project Areas. Galapagos Conservancy. Retrieved June 16, 2013. 

External links

0°02′N 91°20′W / 0.033°N 91.333°W / 0.033; -91.333

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