Coldest place on Earth, mountains buried in ice, and river gorges made by vanished rivers
I. Map Boundaries: 70 to 80 degrees South, 60 to 90 degrees East
II. Country: Antarctic Treaty Secretariat (Station operated by China at Dome Argus)
III. Overview
Amery Ice Shelf and Lambert Glacier occupy a deep rift valley, one of the most prominent bays or indentations in the solid wall of icy land and mountains that is East Antarctica. Lambert is the largest valley glacier in the world. Below the ice of the Amery Ice Shelf, a marine community thrives underneath 700 m of ice and over 1200 m of sea water. Drilling during 2005 into the ice shelf by the Census of Antarctic Marine Life indicates that sponges, fan worms, urchins, and sea snails are abundant.
To the west of the Amery Ice Shelf, the Prince Charles Mountains rise. Approximately 500 million years ago, the Prince Charles Mountains were joined with the western Ghats of India as part of one mountain range. The Amery Oasis, located just west of Amery Shelf, is an ice-free area with a river gorge from a now-vanished river. Coal seams contain fossilized tree remains.
East of Lambert Glacier is the Mawson Escarpment, an ice-free range, and further to the east are the Grove Mountains, which also contain nunatuks extending above the ice. More than 500 miles to the south is another buried mountain range, Gamburtsev. Topography of the Gamburtsev Mountains is similar to that of the European Alps. Dome Argus, on the ice at 13,000 feet, is above the Gamburtsevs and is also where the coldest recorded temperatures have been recorded, at minus 82.5 degrees C.
IV. Terrestrial Ecoregions
AN 1102, Maudlandia Antarctic Desert. Consists of the ice-free coastal fringes. Lichens and moss cushions grow on soil, with some algae on snow. Mean monthly temperatures exceed freezing for a month or less in the summer.
V. Marine Ecoregions
Southern Ocean Realm, Continental High Antarctic Province
224. East Antarctic Wilkes Land
VI. Points of Interest
Amery Oasis, Northern Prince Charles Mountains. An ice-free area west of the Amery Ice Shelf. Although frozen, Beaver Lake exhibits tidal fluctuations. To the west is Radok Lake, which is of unknown depth and drains into Beaver Lake via Pagradroma Gorge. The steep-walled gorge was produced by a now-vanished river. The Bainmedart Coal Measures consist of 110 seams of bituminous coal deposited at the Paleozoic-Mesozoic periods. The coal was deposited within alluvial settings dominated by north-flowing rivers. The presence of upright fossilized stumps indicates the coal was from local plants. There is extensive leaf fossil preservation of Glossopteris, a deciduous seed-bearing tree that may have grown in conditions similar to cypress today. Terrestrial ecoregion AN1102 and Marine Ecoregion 224.
Dome Argus. Located just to the south of the map area at an elevation of 13,000 feet, this is believed to be the coldest spot in Antarctica. The coldest ever was 82.5 degrees C below zero. China’s Kunlun Station is located nearby.
Gamburtsev Mountains. A two-mile deep layer of glacial ice covers mountains the size of the European Alps. The rugged topography of the mountain range under the ice suggests that the ice sheet formed quickly. At the bottom of the ice is liquid water. A map of the mountain range was completed during the 2008-2009 summer season.
Mount Harding and Grove Mountains, American Highland. Antarctic Specially Protected Area No. 168. Mount Harding extends 200 m above the ice, and the ice-free areas allow study of East Antarctic Ice Sheet fluctuations. Features of the preserve are cold desert soil, pools of water, and a crescent-shaped ridge of nunatuks. On the west side is a large blue-ice area, called Kunming Lake, cone-shaped pyramids, and wind-eroded rock formations.
VII. References
Antarctic Treaty Secretariat. Antarctic Protected Areas Database. http://www.ats.aq/devPH/apa/ep_protected_search.aspx?type=2&lang=e (Accessed March 7, 2010).
Antarctic Treaty Secretariat. Management Plan for Antarctic Specially Protected Area No. 168, Mount Harding, Grove Mountains, East Antarctica. www.ats.aq/documents/recatt/Att386_e.pdf (accessed September 25, 2010).
Antarctica’s Gamburtsev Province Project web page. www.ldeo.columbia.edu/res/pi/gambit/index.htm (accessed September 25, 2010).
Australian Antarctic Division. The Amery Oasis, Northern Prince Charles Mountains. www.antarctica.gov.au/living-and-working/stations/mawson/prince-charles-mountains/amery/
(accessed September 25, 2010).
Consortium for Ocean Leadership. Census of Marine Life Discoveries. Amery Ice Shelf. www.coml.org (accessed 5/15/10)
Kenrick, Paul and Paul Davis. 2004. Fossil Plants. Smithsonian Books, Washington, DC.
Olson, David M., et al., 2001. Terrestrial Ecoregions of the World: A New Map of Life on Earth. BioScience 51:933-938. Ecoregion map at http://www.nationgeographic.com/wildworld/terrestrial.html
Prince Charles Mountains, Lambert Glacier and Amery Ice Shelf North. 2004. Scale 1:2,000,000. Map Catalog 13112. Australian Antarctic Data Centre. http://data.aad.gov.au/aadc/mapcat/ (Accessed September 25, 2010).
Prince Charles Mountains, Lambert Glacier, and Amery Ice Shelf South. 2004. Scale 1:2,000,000. Map Catalog 13113. Australian Antarctic Data Centre. http://data.aad.gov.au/aadc/mapcat/ (Accessed September 25, 2010).
Siegert, Martin J. et al. 2005. A revised inventory of Antarctic subglacial lakes. Antarctic Science 17:453-460.
Spalding, Mark D. and 14 others. 2007. Marine Ecoregions of the World: A Bioregionalization of Coastal and Shelf Areas. BioScience 57:573-583.
Wilson, C.J.L. Antarctic Tectonics Website. School of Earth Sciences, University of Melbourne, Victoria, Australia. http://web.earthsci.unimelb.edu.au/antarctica
(accessed September 25, 2010).
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