Earth:Mount Erebus

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Short description: Volcano on Ross Island, Antarctica


Mount Erebus
Mt erebus.jpg
Mount Erebus
Highest point
Elevation3,794 m (12,448 ft) [1]
Prominence3,794 m (12,448 ft) [1]
Ranked 34th
ListingUltra
Coordinates [ ⚑ ] : 77°31′47″S 167°09′12″E / 77.52972°S 167.15333°E / -77.52972; 167.15333 [2]
Geography
Map of Antarctica showing location of Mount Erebus
Map of Antarctica showing location of Mount Erebus
Mount Erebus
Mount Erebus in Antarctica
LocationRoss Island, Antarctica
(claimed by New Zealand as part of the Ross Dependency)
Topo mapRoss Island
Geology
Age of rock1.3 million years
Mountain typeStratovolcano (composite cone)
Volcanic beltMcMurdo Volcanic Group
Last eruptionCurrently erupting
Climbing
First ascent1908 by Edgeworth David and party[3]

Mount Erebus (/ˈɛrɪbəs/) is the second-highest volcano in Antarctica (after Mount Sidley), the highest active volcano in Antarctica, and the southernmost active volcano on Earth. It is the sixth-highest ultra mountain on an island, and the second-highest in Antarctica.[1][4] With a summit elevation of 3,794 metres (12,448 ft), it is located in the Ross Dependency on Ross Island, which is also home to three inactive volcanoes: Mount Terror, Mount Bird, and Mount Terra Nova.[citation needed] The mountain was named by Captain James Clark Ross in 1841 for his ship, the Erebus.[2]

The volcano has been active for around 1.3 million years and has a long-lived lava lake in its inner summit crater that has been present since at least the early 1970s.

On 28 November 1979 Air New Zealand Flight 901 crashed on Mount Erebus killing all 257 people on board.

Geology and volcanology

Anorthoclase crystal (45 mm long) from Mount Erebus

Mount Erebus is the world's southernmost active volcano. It is the current eruptive centre of the Erebus hotspot. The summit contains a persistent convecting phonolitic lava lake, one of five long-lasting lava lakes on Earth. Characteristic eruptive activity consists of Strombolian eruptions from the lava lake or from one of several subsidiary vents, all within the volcano's inner crater.[5][6] 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 (hundreds of metres) to the active vents, a characteristic shared with only a few volcanoes on Earth, such as Stromboli in Italy. Scientific study of the volcano is also facilitated by its proximity to McMurdo Station (U.S.) and Scott Base (New Zealand), both sited on the same island around 35 km away.

Mount Erebus is classified as a polygenetic stratovolcano. The bottom half of the volcano is a shield and the top half is a stratocone. The composition of the current eruptive products of Erebus are anorthoclase-porphyritic tephritic phonolite and phonolite, which are the bulk of exposed lava flow on the volcano. The oldest eruptive products consist of relatively undifferentiated and nonviscous basanite lavas that form the low broad platform shield of Erebus. 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 Erebus. Erebus is the world's only presently erupting phonolite volcano.[7]

Lava flows of more viscous phonotephrite and trachyte erupted after the basanite. The upper slopes of Mount Erebus are dominated by steeply dipping (about 30°) tephritic phonolite lava flows with large-scale flow levees. A conspicuous break in slope around 3,200 m ASL calls attention to a summit plateau representing a caldera. The summit caldera was created by an explosive VEI-6 eruption that occurred 18,000 ± 7,000 years ago.[8] It 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 known as Erebus crystals. The active lava lake in this summit cone undergoes continuous degassing.

Following studies conducted in the early 1990s, it was found that Mount Erebus releases small amounts of gold crystals in the gases produced from the volcano; these crystals range in size from 20 to 60 micrometres. It is estimated that around 80 grams of gold are released by the volcano in this manner each day.[9]

Researchers spent more than three months during the 2007–08 field season installing an atypically dense array of seismometers around Mount Erebus to listen to waves of energy generated by small, controlled blasts from explosives they buried along its flanks and perimeter, and to record scattered seismic signals generated by lava lake eruptions and local ice quakes. By studying the refracted and scattered seismic waves, the scientists produced an image of the uppermost (top few km) of the volcano to understand the geometry of its "plumbing" and how the magma rises to the lava lake. [10][11] These results demonstrated a complex upper-volcano conduit system with appreciable upper-volcano magma storage to the northwest of the lava lake at depths hundreds of meters below the surface.

Ice fumaroles

Mount Erebus is notable for its numerous ice fumaroles – ice towers that form around gases that escape from vents in the surface.[12] The ice caves associated with the fumaroles are dark, in polar alpine environments starved in organics and with oxygenated hydrothermal circulation in highly reducing host rock. The life is sparse, mainly bacteria and fungi. This makes it of special interest for studying oligotrophs – organisms that can survive on minimal amounts of resources.

The caves on Erebus are of special interest for astrobiology,[13] as most surface caves are influenced by human activities, or by organics from the surface brought in by animals (e.g. bats and birds) or ground water.[14] The caves at Erebus are at high altitude, yet accessible for study. Some of the caves can reach temperatures of 25 degrees Celsius (77 degrees Fahrenheit), and with light near the cave mouths, in some caves covered by thin overlying ice the light reach even deeper, is sufficient to sustain an ecosystem of flora and fauna consisting of moss, algae, arthropods and nematodes.[15]

They are dynamic systems that collapse and rebuild, but persist over decades. The air inside the caves has 80 to 100% humidity, and up to 3% carbon dioxide (CO2), and some carbon monoxide (CO) and hydrogen (H2), but almost no methane (CH4) or hydrogen sulfide (H2S). Many of them are completely dark, so cannot support photosynthesis. Organics can only come from the atmosphere, or from ice algae that grow on the surface in summer, which may eventually find their way into the caves through burial and melting. As a result, most micro-organisms there are chemolithoautotrophic i.e. microbes that get all of their energy from chemical reactions with the rocks, and that do not depend on any other lifeforms to survive. The organisms survive using CO2 fixation and some may use CO oxidization for the metabolism. The main types of microbe found there are Chloroflexota and Acidobacteriota.[16][17] In 2019, the Marsden Fund granted nearly NZ$1 million to the University of Waikato and the University of Canterbury to study the micro-organisms in the geothermal fumaroles.[18]

History

Discovery and naming

Mount Erebus was discovered on 27 January 1841 (and observed to be in eruption),[19] by polar explorer Sir James Clark Ross on his Antarctic expedition, who named it and its companion, Mount Terror, after his ships, HMS Erebus and HMS Terror (which were later used by Sir John Franklin on his disastrous Arctic expedition). Present with Ross on HMS Erebus was the young Joseph Hooker, future president of the Royal Society and close friend of Charles Darwin. Erebus is a dark region in Hades in Greek mythology, personified as the Ancient Greek primordial deity of darkness, the son of Chaos.[20]

Historic sites

Photograph of Mount Erebus (and Adélie penguins) taken by the Terra Nova expedition in 1913

The mountain was surveyed in December 1912 by a science party from Robert Falcon Scott's Terra Nova expedition, who also collected geological samples. Two of the camp sites they used have been recognised for their historic significance:

  • Upper “Summit Camp” site (HSM 89) consists of part of a circle of rocks, which were probably used to weight the tent valances.
  • Lower “Camp E” site (HSM 90) consists of a slightly elevated area of gravel, as well as some aligned rocks, which may have been used to weight the tent valances.

They have been designated historic sites or monuments following a proposal by the United Kingdom, New Zealand, and the United States to the Antarctic Treaty Consultative Meeting.[21]

Climbing

Mount Erebus' summit crater rim was first achieved by members of Sir Ernest Shackleton's party; Professor Edgeworth David, Sir Douglas Mawson, Dr Alister Mackay, Jameson Adams, Dr Eric Marshall and Phillip Brocklehurst (who did not reach the summit), in 1908. Its first known solo ascent and the first winter ascent was accomplished by British mountaineer Roger Mear on 7 June 1985, a member of the "In the Footsteps of Scott" expedition.[22] On 19–20 January 1991, Charles J. Blackmer, an iron-worker for many years at McMurdo Station and the South Pole, accomplished a solo ascent in about 17 hours completely unsupported, by snow mobile and on foot.[23][24]

Robotic exploration

In 1992, the inside of the volcano was explored by Dante I, an eight legged tethered robotic explorer.[25] Dante was designed to acquire gas samples from the magma lake inside the inner crater of Mount Erebus to understand the chemistry better through the use of the on-board gas chromatograph, as well as measuring the temperature inside the volcano and the radioactivity of the materials present in such volcanoes. Dante successfully scaled a significant portion of the crater before technical difficulties emerged with the fibre-optic cable used for communications between the walker and base station. Since Dante had not yet reached the bottom of the crater, no data of volcanic significance was recorded. The expedition proved to be highly successful in terms of robotic and computer science, and was possibly the first expedition by a robotic platform to Antarctica.

Air New Zealand Flight 901

Wreckage of Flight 901

Air New Zealand Flight 901 was a scheduled sightseeing service from Auckland Airport in New Zealand to Antarctica and return with a scheduled stop at Christchurch Airport to refuel before returning to Auckland.[26] The Air New Zealand flyover 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 on November 28, 1979, killing all 257 people on board. Passenger photographs taken seconds before the collision ruled out the "flying in a cloud" theory, showing perfectly clear visibility well beneath the cloud base, with landmarks 13 miles (21 km) to the left and 10 miles (16 km) to the right of the aircraft visible.[27] The mountain directly ahead was lit by sunlight shining from directly behind the aircraft through the cloud deck above, resulting in a lack of shadows that made Mount Erebus effectively invisible against the overcast sky beyond in a classic whiteout (more accurately, "flat-light") phenomenon.[28] Further investigation of the crash showed an Air New Zealand navigational error and a cover-up that resulted in about $100 million in lawsuits. Air New Zealand discontinued its flyovers of Antarctica. Its final flight was on February 17, 1980. During the Antarctic summer, snow melt on the flanks of Mount Erebus continually reveals debris from the crash that is visible from the air.[26]

Features

Mount Erebus is in the lower left

Mount Erebus has several named features on its slopes, including a number of craters and rock formations.

Side Crater

[ ⚑ ] 77°31′47″S 167°08′36″E / 77.529609°S 167.14334°E / -77.529609; 167.14334 A nearly circular crater, about 3,700 metres (12,100 ft) high, situated at the summit of Mount Erebus on the southwest crater rim. Named for its location on the side of the main summit cone of Mount Erebus.[29]

Western Crater

[ ⚑ ] 77°31′56″S 167°07′09″E / 77.532253°S 167.119251°E / -77.532253; 167.119251 A small circular crater at 3,561 metres (11,683 ft) high on the western slope of the summit of Mount Erebus. So named for its location.[30]

Nausea Knob

[ ⚑ ] 77°31′16″S 167°08′49″E / 77.521068°S 167.146857°E / -77.521068; 167.146857 A prominent outcropping of jumbled rocks, 3,633 metres (11,919 ft) high, formed as a lava flow on the northwest upper slope of the active cone of Mount Erebus. The feature is near a camp site used mainly in the 1970s by teams working at the summit of the volcano. So named because many working at the camp suffered from nausea due to high elevation mountain sickness.[31]

Tarr Nunatak

[ ⚑ ] 77°28′41″S 166°53′17″E / 77.478006°S 166.888183°E / -77.478006; 166.888183 A nunatak rising to about 1,700 metres (5,600 ft) high on the northwest slope of Mount Erebus. The feature is 1.2 nautical miles (2.2 km; 1.4 mi) south-southwest of Abbott Peak. Named by New Zealand Geographic Board (NZGB) (2000) after Sergeant L.W. (Wally) Tarr, Royal New Zealand Air Force, aircraft mechanic with the New Zealand contingent of the Commonwealth Trans-Antarctic Expedition (CTAE), 1956-58.[32]

Seismic Bluff

[ ⚑ ] 77°31′54″S 167°04′47″E / 77.531538°S 167.079644°E / -77.531538; 167.079644 Steep bluff at about 3,470 metres (11,380 ft) high on the southwest rim of the summit caldera of Mount Erebus.[33] So named after a seismic station nearby.

Cashman Crags

[ ⚑ ] 77°32′26″S 166°51′02″E / 77.540504°S 166.850438°E / -77.540504; 166.850438 Two rock summits at about 1,500 metres (4,900 ft) high on the west slope of Mount Erebus. The feature is 0.6 nautical miles (1.1 km; 0.69 mi) southwest of Hoopers Shoulder. At the suggestion of P.R. Kyle, named by United States Advisory Committee on Antarctic Names (US-ACAN) (2000) after Katherine V. Cashman, United States Antarctic Research Program (USARP) team member on Mount Erebus in 1978-79 while a Fulbright scholar at Victoria University of Wellington; worked again on Mount Erebus, 1988-89; later Professor of Geology, University of Oregon.[34]

Nearby features

Features around Mount Erebus include Fang Ridge, Abbot Peak, Hoopers Shoulder, Three Sisters Cones, Williams Cliff and Turks Head Ridge.[35]

Fang Ridge

[ ⚑ ] 77°29′S 167°12′E / 77.483°S 167.2°E / -77.483; 167.2. A conspicuous ridge on the northeast slope of Mount Erebus, on Ross Island. It is a much denuded portion of the original caldera rim left by a catastrophic eruption. So named, probably for its curved shape, by Frank Debenham of the British Antarctic Expedition, 1910-13, who made a plane table survey in 1912.[36]

Abbott Peak

[ ⚑ ] 77°26′S 167°00′E / 77.433°S 167°E / -77.433; 167. Pyramidal peak on Ross Island, on the north side of Mount Erebus, between it and Mount Bird. Charted by the British Antarctic Expedition under Scott, 1910-13, and named for Petty Officer George P. Abbott, Royal Navy, a member of the expedition. Not: Abbotts Peak, Demetri's Peak, Dimitri Peak.[37]

Hoopers Shoulder

[ ⚑ ] 77°32′S 166°53′E / 77.533°S 166.883°E / -77.533; 166.883. An independent cone at an elevation of 1,800 metres (5,900 ft) high on the west slopes of Mount Erebus on Ross Island. From McMurdo Sound it appears as a perfect pyramid of black rock, standing out as a splendid mark against the background of the ice and almost on a line from Cape Royds to the crater of Mount Erebus. The cone itself is about 100 metres (330 ft) high high and is surrounded by a deep moat or ditch, caused by the sweeping action of strong winds. It was named by F. Debenham on the second ascent of Mount Erebus for F.J. Hooper, a steward of the British Antarctic Expedition, 1910-13. Hooper was one of the party making the second ascent.[38]

Three Sisters Cones

[ ⚑ ] 77°34′S 166°58′E / 77.567°S 166.967°E / -77.567; 166.967. Three aligned cones at an elevation of about 1,800 metres (5,900 ft) high on the southwest slopes of Mount Erebus on Ross Island. Named by members of the British Antarctic Expedition, 1910-13, under Scott.[39]

Williams Cliff

[ ⚑ ] 77°35′S 166°47′E / 77.583°S 166.783°E / -77.583; 166.783. A prominent rock cliff that stands out from the ice-covered southwest slopes of Mount Erebus, situated 6 nautical miles (11 km; 6.9 mi) east of Cape Barne on Ross Island. This rock cliff was mapped by the British Antarctic Expedition under Scott, 1910-13, and identified simply as "Bold Cliff on maps resulting from that expedition. It was named Williams Cliff by the US-ACAN in 1964 to commemorate Richard T. Williams, who losi: his life when his tractor broke through the ice at McMurdo Sound in January 1956. [40]

Turks Head Ridge

[ ⚑ ] 77°38′S 166°49′E / 77.633°S 166.817°E / -77.633; 166.817. A mostly ice-covered ridge in the southwest part of Ross Island, extending from Turks Head for a few miles up the slopes of Mount Erebus. Mapped by the British Antarctic Expedition (1910-13) under Scott and so named because of its association with Turks Head.[41]

Image gallery

  • Aerial view of Mount Erebus craters

  • Satellite picture of Mount Erebus showing glow from its persistent lava lake

  • Mount Erebus in December 1955

See also

  • Charles Neider
  • Coleman Peak
  • Erebus Glacier
  • Erebus Ice Tongue
  • Ice Tower Ridge
  • List of volcanoes in Antarctica
  • Lower Erebus Hut – home of MEVO
  • Volcanic Seven Summits
  • Helo Cliffs, a prominent feature on the caldera

References

  1. ↑ 1.0 1.1 1.2 "Mount Erebus". Smithsonian Institution. https://volcano.si.edu/volcano.cfm?vn=390020. 
  2. ↑ 2.0 2.1 Alberts 1995, p. 223.
  3. ↑ "Antarctic explorers". Australian Antarctic Division. http://www.aad.gov.au/default.asp?casid=6740. 
  4. ↑ Antarctica Ultra-Prominences, Aaron Maizlish, http://peaklist.org/WWlists/ultras/antarctica.html 
  5. ↑ Kyle, P. R., ed (1994). Volcanological and Environmental Studies of Mount Erebus, Antarctica. Antarctic Research Series. Washington DC: American Geophysical Union. ISBN 0-87590-875-6. OCLC 1132108108. 
  6. ↑ Aster, R.; Mah, S.; Kyle, P.; McIntosh, W.; Dunbar, N.; Johnson, J. (2003). "Very long period oscillations of Mount Erebus volcano". J. Geophys. Res. 108 (B11): 2522. doi:10.1029/2002JB002101. Bibcode: 2003JGRB..108.2522A. 
  7. ↑ Burgisser, Alain; Oppenheimer, Clive; Alletti, Marina; Kyle, Philip R.; Scaillet, Bruno; Carroll, Michael R. (November 2012). "Backward Tracking of Gas Chemistry Measurements at Erebus Volcano". Geochemistry, Geophysics, Geosystems 13 (11). doi:10.1029/2012GC004243. Bibcode: 2012GGG....1311010B. https://hal-insu.archives-ouvertes.fr/insu-00771966/file/ggge2328.pdf. 
  8. ↑ "VOGRIPA". http://www.bgs.ac.uk/vogripa/searchVOGRIPA.cfc?method=detail&id=2421. 
  9. ↑ Hecht, Jeff (7 September 1991). "Science: Antarctic gold dust" (in en-US). https://www.newscientist.com/article/mg13117853-300-science-antarctic-gold-dust/. 
  10. ↑ "Plumbing Erebus: Scientists use seismic technique to map interior of Antarctic volcano". http://antarcticsun.usap.gov/science/contenthandler.cfm?id=1355. 
  11. ↑ Zandomeneghi, D.; Aster, R.; Kyle, P.; Barclay, A.; Chaput, J.; Knox, H. (2013). "Internal structure of Erebus volcano, Antarctica imaged by high-resolution active-source seismic tomography and coda interferometry". Journal of Geophysical Research 118 (3): 1067–1078. doi:10.1002/jgrb.50073. Bibcode: 2013JGRB..118.1067Z. 
  12. ↑ For photographs of ice fumaroles, see Ice Towers Mount Everest Volcano Observatory
  13. ↑ "Descent into a Frozen Underworld" (in en-US). 2017-02-17. https://www.astrobio.net/alien-life/descent-frozen-underworld/. 
  14. ↑ AnOther (2015-06-18). "Mount Erebus: A Tale of Ice and Fire" (in en). https://www.anothermag.com/design-living/7522/mount-erebus-a-tale-of-ice-and-fire. 
  15. ↑ "Secret Life May Thrive Under Warm Antarctic Caves". 2017-09-09. https://www.geologyin.com/2017/09/secret-life-may-thrive-under-warm.html. 
  16. ↑ Tebo, Bradley M.; Davis, Richard E.; Anitori, Roberto P.; Connell, Laurie B.; Schiffman, Peter; Staudigel, Hubert (2015). "Microbial communities in dark oligotrophic volcanic ice cave ecosystems of Mt. Erebus, Antarctica". Frontiers in Microbiology 6: 179. doi:10.3389/fmicb.2015.00179. ISSN 1664-302X. PMID 25814983. 
  17. ↑ Wall, Mike (9 December 2011). "Antarctic Cave Microbes Shed Light on Life's Diversity". http://www.livescience.com/17402-antarctica-mount-erebus-ice-cave-diversity.html. 
  18. ↑ Harris, Rosie (2019). "Micro-organisms in the volcanic vents of Erebus - a key to life on other planets?". Antarctic 38 (3 & 4): 14–15. ISSN 0003-5327. 
  19. ↑ Ross, J.C. (1847). A Voyage of Discovery and Research in the Southern and Antarctic Regions, During the Years 1839-43. 1. John Murray. p. 216-218. https://books.google.com/books?id=kjoNAAAAIAAJ&pg=PA216. 
  20. ↑ Hesiod, Theogony 116–124.
  21. ↑ "List of Historic Sites and Monuments approved by the ATCM (2013)". Antarctic Treaty Secretariat. 2013. http://www.ats.aq/documents/ATCM36/WW/atcm36_ww004_e.pdf. 
  22. ↑ Mear, Roger; Swan, Robert; Fulcher, Lindsay (1987) (in English). A Walk to the Pole: To the Heart of Antarctica in the Footsteps of Scott. Crown. pp. 95–104. ISBN 978-0-517-56611-4. OCLC 16092953. 
  23. ↑ Wheeler, Sara (1998). Terra Incognita. Random House. ISBN 9780679440789. https://archive.org/details/terraincognita00sara. 
  24. ↑ Johnson, Nicholas (2005). Big Dead Place. Feral House. ISBN 9780922915996. https://archive.org/details/bigdeadplaceinsi00nich. 
  25. ↑ Wettergreen, David; Thorpe, Chuck; Whittaker, Red (December 1993). "Exploring Mount Erebus by Walking Robot". Robotics and Autonomous Systems 11 (3–4): 171–185. doi:10.1016/0921-8890(93)90022-5. 
  26. ↑ 26.0 26.1 Holmes, Paul (2011) (in English). Daughters of Erebus. Hodder Moa. p. 31. ISBN 978-1-86971-250-1. OCLC 740446014. 
  27. ↑ Royal Commission Report, para 28
  28. ↑ Royal Commission Report, para 40(a)
  29. ↑ Side Crater USGS.
  30. ↑ Western Crater USGS.
  31. ↑ Nausea Knob USGS.
  32. ↑ Tarr Nunatak USGS.
  33. ↑ Seismic Bluff USGS.
  34. ↑ Cashman Crags USGS.
  35. ↑ Ross Island USGS.
  36. ↑ Alberts 1995, p. 232.
  37. ↑ Alberts 1995, p. 1.
  38. ↑ Alberts 1995, p. 344.
  39. ↑ Alberts 1995, p. 745.
  40. ↑ Alberts 1995, p. 815.
  41. ↑ Alberts 1995, p. 764.

Sources

External links

Mount Erebus travel guide from Wikivoyage



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