Mount Erebus
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| Mount Erebus | |
|---|---|
 Mt. Erebus, 1972 |
|
| Elevation | 3,794 metres (12,448 feet) |
| Location | Ross Island, Antarctica |
| Prominence | 3,794 m |
| Coordinates | |
| Type | Stratovolcano |
| Age of rock | 1 million years |
| Last eruption | 2006 (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. 3794 metres (12,448 ft) high, it is located on Ross Island, which is also home to three inactive volcanoes, notably Mt. Terror.
The volcano has been continuously active since 1972 and is the site of the Mt. Erebus Volcano Observatory run by the New Mexico Institute of Mining and Technology. The crater is home to one of the very few permanent lava lakes in the world.
Mount Erebus was discovered in 1841 by polar explorer Sir James Clark Ross (whose ships were named Erebus and Terror; these ships were also used by Sir John Franklin on his disastrous Arctic expedition), and first climbed (to the rim) by members of Sir Ernest Shackleton's party in 1908. The ships and the volcano were all named for Erebus, a primordial Greek god, the son of Chaos.
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[edit] Geology
Mt. Erebus is currently the most active volcano in Antarctica. The summit of Mt. Erebus contains a persistent convecting lava lake which undergoes several strombolian style eruptions daily. In 2005, small ash eruptions and even a small lava flow were observed coming from vents near the lava lake. The bottom half of the volcano is a shield and the top half is a stratocone (Mount Etna is like this as well).
Mt. Erebus (3794 meters above sea level) is classified as a polygenetic stratovolcano. The composition of the current eruptive activity on 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. The volcano frequently produces Strombolian eruptions from several vents within its innermost crater, with the most frequent events arising from large (up to 10-m diameter) gas bubbles emerging explosively from the lava lake.
[edit] Air disaster
Air New Zealand Flight 901 was a non-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] See also
- Nimrod Expedition - first ascent of Mount Erebus
[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 a live cam of the volcano, video clips of eruptions and other geological information. The Observatory is supported by the National Science Foundation Office of Polar Programs
- A Panoramic View from the summit of Mt. Erebus
