Mount Erebus
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| Mount Erebus | |
|---|---|
 Mt. Erebus, 1972 |
|
| Elevation | 3,794 meters (12,448 feet) |
| Location | Ross Island, Antarctica |
| Prominence | 3,794 m |
| Coordinates | |
| Type | Stratovolcano |
| Age of rock | 1 million years |
| Last eruption | 2007 (continuing) |
| First ascent | 1908 from a party led by T.W.E. David |
| Easiest route | basic snow/ice climb |
Mount Erebus in Antarctica is the southernmost active volcano on Earth. 3,794 meters (12,448 ft) high, it is located on Ross Island, which is also home to three inactive volcanoes, notably Mt. Terror. Mount Erebus is part of the Pacific Ring of Fire, which includes over 160 active volcanoes.
The volcano has been observed to be continuously active since 1972 and is the site of the Mt. Erebus Volcano Observatory run by New Mexico Tech.
Mount Erebus was discovered in 1841 (and observed to be in eruption) by polar explorer Sir James Clark Ross who named it and Mount Terror after his ships, Erebus and Terror (which were also used by Sir John Franklin on his disastrous Arctic expedition). It was first climbed (to the rim) by members of Sir Ernest Shackleton's party in 1908. Erebus was a primordial Greek god, the son of Chaos.
The first known solo ascent of Mount Erebus was accomplished by Charles J. Blackmer on January 19-20, 1991. Blackmer, an Ironworker for many years at McMurdo Station and the South Pole, accomplished this in a twenty four hour period. The ascent took approximately 17 hours. This event has been cited in two books about Antarctic experiences, Terra Incognita by Sara Wheeler and Big Dead Place by Nicholas Johnson.
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[edit] Geology and Volcanology
Mt. Erebus is currently the most active volcano in Antarctica. The summit of Mt. Erebus contains a persistent convecting phonolitic lava lake, one of a very few long-lived lava lakes in the world. Characteristic eruptive activity consists of Strombolian eruptions from the lava lake or from one of several subsidiary vents, all lying within the volcano's inner crater.[1][2] The volcano is scientifically remarkable in that its relatively low-level and unusually persistent eruptive activity enables long-term volcanological study of a Strombolian eruptive system very close (100's of m) to the active vents, a characteristic shared with only a few volcanos worldwide, such as Stromboli, Italy. Scientific study of the volcano is also facilitated by the proximity (35 km) of McMurdo Station (US) and Scott Base (NZ), both sited on Ross Island.
Mt. Erebus is classified as a polygenetic stratovolcano. The bottom half of the volcano is a shield and the top half is a stratocone (Mount Etna is like this as well). The composition of the current eruptive products of Mt. Erebus is anorthoclase-porphyric tephritic phonolite and phonolite, which constitute the bulk of exposed lava flow on the volcano. The oldest eruptive products from Mt. Erebus consist of relatively undifferentiated and non-viscous basanitic lavas that form the low, broad platform shield of the Erebus edifice. Slightly younger basanite and phonotephrite lavas crop out on Fang Ridge, an eroded remnant of an early Erebus volcano and at other isolated locations on the flanks of the Mt. Erebus edifice.
Lava flows of more viscous phonotephrite, tephriphonolite and trachyte were erupted after the basanite. The upper slopes of Mt. Erebus are dominated by steeply dipping (~30°) tephritic phonolite lava flows with large scale flow levees. A conspicuous break in slope at approximately 3200 meters is a summit plateau representing a caldera less than 100,000 years old. The summit caldera itself is filled with small volume tephritic phonolite and phonolite lava flows. In the center of the summit caldera is a small, steep-sided cone composed primarily of decomposed lava bombs and a large deposit of anorthoclase crystals. It is within this summit cone that the active lava lake continuously degasses.
[edit] Air disaster
Air New Zealand Flight 901 was a scheduled passenger transport service from Auckland International Airport in New Zealand to Antarctica and return. The Air New Zealand service, for the purposes of Antarctic sightseeing, was operated with McDonnell Douglas DC-10-30 aircraft and began in February 1977. The flight crashed into Mount Erebus in 1979, killing all 257 people aboard.
[edit] Notes and references
- ^ Kyle, P. R. (Ed.), Volcanological and Environmental Studies of Mount Erebus, Antarctica, Antarctic Research Series, American Geophysical Union, Washington DC, 1994.
- ^ Aster R., Mah, S., Kyle, P., McIntosh, W., Dunbar, N., and J. Johnson, Very long period oscillations of Mount Erebus volcano, J. Geophys. Res., 108, 2522, doi:10 .1029/2002JB002101, 2003.
[edit] See also
- Nimrod Expedition - first ascent of Mount Erebus
- Volcanic Seven Summits
[edit] External links
- Global Volcanism Program
- A picture from space of the lava lake at the summit of Mt Erebus
- Erebus Glacier Tongue
- The Mount Erebus Volcano Observatory website at New Mexico Tech includes seasonally available live camera images of the volcano's lava lake, video clips of eruptions and other geological and geophysical information. The Observatory is supported by the U.S. National Science Foundation Office of Polar Programs
- A Panoramic View from the summit of Mt. Erebus
- Footage of Mt. Erebus erupting in 2005
