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Axel Heiberg Island

Coordinates:79°45′N091°00′W / 79.750°N 91.000°W /79.750; -91.000[1]
From Wikipedia, the free encyclopedia
Uninhabited island in the Qikiqtaaluk Region, Nunavut, Canada
Not to be confused withHeiberg Islands, which are named after the same person

Axel Heiberg
Native name:
ᐅᒥᖕᒪᑦ ᓄᓈᑦ
Shaded relief map of Axel Heiberg Island. Note that the colours are indicative of elevation, not foliage or ground cover.
Location of Axel Heiberg Island
Axel Heiberg is located in Nunavut
Axel Heiberg
Axel Heiberg
Show map of Nunavut
Axel Heiberg is located in Canada
Axel Heiberg
Axel Heiberg
Show map of Canada
Geography
LocationArctic Ocean
Coordinates79°45′N091°00′W / 79.750°N 91.000°W /79.750; -91.000[1]
ArchipelagoSverdrup Islands
Queen Elizabeth Islands
Arctic Archipelago
Area43,178 km2 (16,671 sq mi)
Area rank32nd
Length371 km (230.5 mi)
Width220–246 km (137–153 mi)
Highest elevation2,210 m (7250 ft)
Highest pointOutlook Peak
Administration
Canada
TerritoryNunavut
RegionQikiqtaaluk
Demographics
Population0

Axel Heiberg Island (Inuktitut:ᐅᒥᖕᒪᑦ ᓄᓈᑦ,Umingmat Nunaat) is anuninhabited island in theQikiqtaaluk Region,Nunavut, Canada. Located in theArctic Ocean, it is the32nd largest island in the world andCanada's seventh largest island. According toStatistics Canada,[2] it has an area of 43,178 km2 (16,671 sq mi). It is named afterAxel Heiberg.

One of the larger members of theArctic Archipelago, it is also a member of theSverdrup Islands andQueen Elizabeth Islands. It is known for its unusualfossil forests, which date from theEocene period.[3] Owing to the lack of mineralization in many of the forest specimens, the traditional characterization of "fossilisation" fails for these forests and "mummification" may be a more precise description. The fossil records provide strong evidence that the Axel Heiberg forest was a high-latitude wetland forest.[4] Aholotype of theammoniteOtoceras gracile was found in theGriesbachian (EarlyTriassic) deposits of this island.[5]

History

[edit]
Topography of Axel Heiberg Island
Satellite photo montage of Axel Heiberg Island

Axel Heiberg Island has been inhabited in the past by theInuit,[6][7] but was uninhabited by the time it was named byOtto Sverdrup, who explored it in 1900–01. He named it afterAxel Heiberg, financial director of the NorwegianRingnes brewery which sponsored the expedition.[8] Other explorers visited the island during the early 20th century, during which time it was claimed byNorway until 1930. It is now part of Nunavut Territory, Canada. It was not until the late 1940s that the island was aerially photographed by theUnited States Army Air Forces' Operation Polaris. In 1955, twogeologists of theGeological Survey of Canada, N.J. McMillan and Souther, traversed the interior as part of Operation Franklin. McMillan's observations of Bunde Glacier in northwest Axel Heiberg Island are the earliest glaciological observations on the ground to have found their way into a scientific publication.

In 1959, scientists fromMcGill University explored Expedition Fiord (previously Sør Fjord or South Fiord) in central Axel Heiberg Island. This resulted in the establishment of theMcGill Arctic Research Station (79°26′N90°46′W / 79.433°N 90.767°W /79.433; -90.767 (McGill Arctic Research Station)), constructed 8 km (5.0 mi) inland from Expedition Fjord in 1960. It comprises a small research hut, a cookhouse, and two temporary structures comfortably accommodating 8–12 persons. The station was initially heavily utilized during the early 1960s, with a population of 20. The McGill Arctic Research Station is active from March to August, and research is currently focused on polar geomorphology, geology, glaciology,permafrost, climate change, and polar microbiology. Over the last 10–15 years, it has served as a significant Mars analogue for astrobiology investigations studying life and habitability of polar cryoenvironments and field-testing planetary exploration instrumentation platforms.

In the summer of 1972, a BritishArmy Mountaineering Association expedition resulted in the naming ofScaife Glacier following the accidental death of Sergeant Kenneth Scaife.

During the summer of 1986, a Canadian expedition headed by Dr. James Basinger set out to investigate a very unusual fossil forest on Axel Heiberg. The findings of these and subsequent expeditions have since been popularly reported in Canada.[9][10][11] Over 40 million years ago, during the Eocene epoch, a forest of tall trees flourished on Axel Heiberg Island. The trees reached up to 35 m (115 ft) in height; some may have grown for 500 to 1,000 years. The polar climate was warm at the time, but the winters were still continuously dark for three months. As the trees fell, the fine sediment in which the forest grew protected the plants. Instead of turning intopetrified "stone" fossils, they were ultimately mummified by the cold, dry Arctic climate and only recently exposed to erosion.[12] Scientists from the Komarov Botanical Institute of the Russian Academy of Sciences in Saint Petersburg provided a few grams of Metasequoia conifer wood from the site to genetics researchers at the National University of Altai, who compared the DNA sequences of the ancient wood with DNA of modern woody plants and found them to be almost identical.[13] Komarov Institute scientists also discovered double-strand DNA molecules in Metasequoia fossil leaves from Axel Heiberg Island.[14]

As late as 1999, preserving this unique site was a concern, as the fossil wood was easily damaged and eroded once exposed. There were concerns that Arctic cruise ship tourists were taking wood and that the site was being disturbed by Canadian military helicopters from nearby bases and even by scientists in their studies.[15] There were calls for more protection for the area. It has no official status, partly because land claims had to be settled. But now Nunavut is looking at how best to protect the fossil forest, possibly by setting up a territorial park to be called Napaaqtulik, "where there are trees".[12][16]

Interesting animal fossils have been discovered on the island, including a remarkably preserved specimen of an ancientAurorachelys turtle and, identified in 2016, thehumerus of aTingmiatornis bird.[17][18]

Glaciation

[edit]

White Glacier is avalley glacier occupying 38.7 km2 (14.9 sq mi) in the Expedition Fiord area of Axel Heiberg Island (79°30′N090°50′W / 79.500°N 90.833°W /79.500; -90.833 (White Glacier)). It extends in elevation from 56 to 1,782 m (184 to 5,846 ft) above sea level, a range which, as noted by Dyurgerov (2002),[19] is exceeded only byDevon Ice Cap in the world list of glaciers with measured mass balance. Ice thickness reaches or exceeds 400 m (1,300 ft). Its maximum extension in recent history, marking the glacier's advance in response to the cooling of theLittle Ice Age, was reached not earlier than the late 18th century and probably at the beginning of the 20th century. There is evidence that the retreat of the terminus, previously at about 5 m (16 ft) per year, is decelerating (Cogley et al. 1996a; Cogley and Adams 2000). White Glacier has been the subject of many papers in the glaciological literature since 1960, e.g.[20][21][22] Müller (1962)[20] was the source of a now-classical diagram elaborating and illustrating the concept of "glacier facies".

Population

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The island is uninhabited except for the seasonalMcGill Arctic Research Station operated byMcGill University.

Lost Hammer Spring

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TheLost Hammer Spring, located in the central west region of the island (79°07′N090°21′W / 79.117°N 90.350°W /79.117; -90.350 (Lost Hammer Spring)) is the coldest and saltiest of allArctic springs described to date. It is characterized by a perennial hypersaline (24%) discharge at subzero temperatures (~−5 °C (23 °F)) flowing to the surface through a hollow, 2 m (6 ft 7 in) high cone-shaped salttufa structure. Continuous gas emissions from the spring indicate an underlying thermogenicmethane source. Based on these properties, this spring is considered a significantastrobiology analogue site for possible habitats currently present onMars and the cold moonsEuropa andEnceladus.

Microbes have been found at this site that do not depend on organic material or oxygen but only on simple inorganic compounds. These inorganic compounds are present on Mars.[23]

Views of the island

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  • Glacier Fiord, Axel Heiberg Island. June 6, 1975.
    Glacier Fiord, Axel Heiberg Island. June 6, 1975.
  • View from Wolf Mountain over the Expedition Valley towards southern Axel Heiberg Island. June 24, 1975.
    View from Wolf Mountain over the Expedition Valley towards southern Axel Heiberg Island. June 24, 1975.
  • Outcrops on Axel Heiberg Island. July 2, 2012.
    Outcrops on Axel Heiberg Island. July 2, 2012.
  • Axel Heiberg Island, Expedition Valley with White Glacier (left) and Thompson Glacier (right). July 3, 1988.
    Axel Heiberg Island, Expedition Valley with White Glacier (left) and Thompson Glacier (right). July 3, 1988.
  • Front of advancing White Glacier, Axel Heiberg Island, June 23, 1975. The steep glacier front with waterfalls is caused by cold glacier ice, the ice cliff shows shear moraines with debris, part of the well-known Thompson Glacier with its push moraine at right. Foreground: vegetation cover of Saxifraga.
    Front of advancing White Glacier, Axel Heiberg Island, June 23, 1975. The steep glacier front with waterfalls is caused by cold glacier ice, the ice cliff shows shear moraines with debris, part of the well-known Thompson Glacier with its push moraine at right. Foreground: vegetation cover of Saxifraga.
  • The active push moraine of Thompson glacier in July 1988
    The active push moraine of Thompson glacier in July 1988

See also

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References

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  1. ^"Axel Heiberg Island".Geographical Names Data Base.Natural Resources Canada.
  2. ^Area of major sea islands, by regionArchived August 12, 2004, at theWayback Machine
  3. ^"The Fossilized Forest Of Axel Heiberg Island". The University of British Columbia. Retrieved15 November 2019.
  4. ^Williams, C.J.; Johnson, A.H.; LePage, B.A.; Vann, D.R.; Sweda, T. (2003). "Reconstruction of Tertiary Metasequoia Forests II". Structure, Biomass and Productivity of Eocene Floodplain Forests in the Canadian Arctic".Paleobiology.29 (2):271–292.doi:10.1666/0094-8373(2003)029<0271:rotmfi>2.0.co;2.S2CID 131497232.
  5. ^Kutygin R.V., Budnikov I.V., Biakov A.S., Davydov V.I., Kilyasov A.N., Silantiev V.V. (2019)."First findings ofOtoceras (Ceratitida) in the Kobyuma zone of the Southern Verkhoyansk region, Northeastern Russia"(PDF).Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki (in Russian).161 (4): 557.doi:10.26907/2542-064X.2019.4.550-570.Archived(PDF) from the original on 31 March 2022.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  6. ^Schledermann, Peter (1975)."A Late Dorset Site on Axel Heiberg Island".Arctic.28 (4): 300.doi:10.14430/arctic2847.
  7. ^Kalkreuth, Wolfgang; Sutherland, Patricia D. (1998)."The Archaeology and Petrology of Coal Artifacts from a Thule Settlement on Axel Heiberg Island, Arctic Canada".Arctic.51 (4):345–349.doi:10.14430/arctic2847.JSTOR 40511852.
  8. ^Barr, Susan (28 September 2014)."Axel Heiberg". InHelle, Knut (ed.).Norsk biografisk leksikon (in Norwegian). Oslo: Kunnskapsforlaget. Retrieved8 December 2016.
  9. ^Thurston, Harry "Icebound Eden" in Equinox (Camden East, Ont) 3:72. 1986
  10. ^Basinger, James F "Our 'Tropical' Arctic" in Canadian Geographic (Ottawa) 106:28. 1987
  11. ^Foster, Janet "Journey to the Top of the World" Toronto: Greey de Pencier. 1987
  12. ^abhttp://www.nunatsiaqonline.ca/stories/article/263419_nunavut_considers_a_new_park_for_axel_heibergs_fossil_forest/ Nunatsiaq Online, 26 October
  13. ^Samuel Daniel, "Russia first decoded DNA of ancient trunk" (17 December 2018)https://scienceinfo.net/russia-first-decoded-dna-of-ancient-trunk.html
  14. ^Igor A. Ozerov et al., "Use of DNA-specific stains as indicators of nuclei and extranuclear substances in leaf cells of the Middle Eocene Metasequoia from Arctic Canada" inReview of Palaeobotany and Palynology, Volume 279, August 2020, 104211:https://doi.org/10.1016/j.revpalbo.2020.104211
  15. ^C. Bigras; M. Bilz; D. Grattan & C. Gruchy (1995)."Erosion of the Geodetic Hills Fossil Forest, Axel Heiberg Island, Northwest Territories".Arctic.48 (4):342–353.doi:10.14430/arctic1258.
  16. ^Jahren, A.H. (2007). "The Arctic Forest of the Middle Eocene".Annual Review of Earth and Planetary Sciences.35 (1):509–540.Bibcode:2007AREPS..35..509J.doi:10.1146/annurev.earth.35.031306.140125.S2CID 130545959.
  17. ^Wall, Michael (1 February 2009)."Tropical Turtle Fossil Discovered in the High Arctic".Wired.
  18. ^Bono, Richard (19 December 2016)."A Large Ornithurine Bird (Tingmiatornis arctica) from the Turonian High Arctic: Climatic and Evolutionary Implications".Nature.6 38876.Bibcode:2016NatSR...638876B.doi:10.1038/srep38876.PMC 5171645.PMID 27991515.
  19. ^Dyurgerov, M.B. (2002). "Glacier Mass Balance and Regime: Data of Measurements and Analysis".Occasional Paper 55, Institute of Arctic and Alpine Research, University of Colorado.
  20. ^abMüller, F. (1962)."Zonation of the accumulation area of the glaciers of Axel Heiberg Island, N.W.T."Journal of Glaciology.4 (33):302–310.doi:10.1017/S0022143000027623.
  21. ^Blatter, H. (1987)."On the thermal regime of an arctic valley glacier: a study of White Glacier, Axel Heiberg Island, N.W.T., Canada".Journal of Glaciology.33 (114):200–211.Bibcode:1987JGlac..33..200B.doi:10.1017/S0022143000008704.
  22. ^Cogley, J.G.; W.P. Adams; M.A. Ecclestone; F. Jung-Rothenhäusler & C.S.L. Ommanney (1996)."Mass balance of White Glacier, Axel Heiberg Island, N.W.T., Canada, 1960-91".Journal of Glaciology.42 (142):548–563.Bibcode:1996JGlac..42..548C.doi:10.1017/S0022143000003531.
  23. ^A blueprint for life forms on Mars?

Further reading

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External links

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