Brown Bluff

For the rock art site in northwestern Arkansas, see Brown Bluff (Washington County, Arkansas).

Brown Bluff

Brown Bluff is a basalt tuya located on the Tabarin Peninsula of northern Antarctica.^[1] It formed in the past 1 million years, which erupted subglacially within an englacial lake. The volcano's original diameter is thought to have been about 12-15 kilometers, and probably formed by a single vent. Brown Bluff is subdivided into four stages: pillow volcano, tuff cone, slope failure, and hyaloclastite delta and into five structural units.^[2]

The volcano is named "Brown Bluff" because of its steep slopes and its brown-to-black hyaloclastite.

Environment

Topography

Volcanic tephra at Brown Bluff, Antarctica (2016)

Brown Bluff has a 1.5 km long cobble and ash beach rising increasingly steeply towards towering red-brown tuff cliffs which are embedded with volcanic bombs and tephra. The cliffs are heavily eroded, resulting in loose scree and rock falls on higher slopes, and large, wind eroded boulders on the beach. Permanent ice and tidewater glaciers surround the site to the north and south, occasionally filling the beach with brash ice.

Flora and fauna

Lichens in the genera Xanthoria and Caloplaca have been recorded on exposed boulders from the shoreline to an elevation of 185 m. Mosses occur at higher elevations near glacial drainage.

The site has been identified as an Important Bird Area (IBA) by BirdLife International because it supports a breeding colony of about 20,000 pairs of adelie , as well as about 550 pairs of gentoos. Other birds nesting there include Cape petrels, Wilson's storm petrels and kelp gulls.^[3] Weddell seals regularly haul out and leopard seals often hunt offshore.

References

↑ Elias, Scott A.; Mock, Cary J. (2013). "Encyclopedia of Quaternary Science". Elsevier.
↑ Skilling, I. P. (1994) Evolution of an englacial volcano: Brown Bluff, Antarctica, Bulletin of Volcanology, Volume 56, Issue 6-7, pages 573-591. Retrieved on 2007-11-11
↑ "Brown Bluff". BirdLife data zone: Important Bird Areas. BirdLife International. 2012. Retrieved 2012-12-10.

"Antarctic Treaty Visitor Guidelines, Brown Bluff" (PDF). Retrieved 2011-03-13.

Important Bird Areas of Antarctica

Graham Land	Apéndice Island Armstrong Reef Arthur Harbour Avian Island Bates Island Breaker Island Brown Bluff Cape Evensen Cape Wollaston Cierva Point Cockburn Island Cormorant Island Cuverville Island D'Urville Monument Danger Islands Devil Island Dion Islands Dream Island Duroch Islands Eden Rocks Elephant Rocks Gerlache Island Ginger Islands Gourdin Island Guépratte Island Hope Bay Humble Island Joubin Islands Litchfield Island Madder Cliffs Midas Island Moss Islands Murray Island Norsel Point Paulet Island Pearl Rocks Penguin Point Petermann Island Pursuit Point Snow Hill Island Stonington Island Torgersen Island Trinity Island Tupinier Islands Uruguay Island

South Shetlands	Admiralty Bay Ardley Island Aspland Island Baily Head Barnard Point Byers Peninsula Cape Bowles Cape Garry Cape Hooker Cape Lookout Cape Melville Cape Shirreff Cape Wallace Chinstrap Cove Davey Point Eadie Island East of Nelly Point Escarpada Point False Round Point Fur Seal Point Gibbs Island Half Moon Island Harmony Point Heywood Island Jameson Point Kellick Island Lions Rump Milosz Point Mount Elder North Foreland O'Brien Island Owen Island Penguin Island Point Wordie Potter Peninsula Pottinger Point Saddleback Point Seal Islands Stigant Point Stinker Point Tartar Island Vapour Col Yankee Harbour

South Orkneys	Atriceps Island Buchanan Point Cape Davidson Cape Geddes Cape Hansen Cape Robertson Cape Whitson Cheal Point Christoffersen Island Eillium Island Ferguslie Peninsula Ferrier Peninsula Fraser Point Fredriksen Island Gibbon Bay Gosling Islands Graptolite Island Grey Island Inaccessible Islands Larsen Islands Matthews Island Michelsen Island Moe Island Moreton Point Pirie Peninsula Point Martin Return Point Robertson Islands Signy Island Skilling Island Southern Powell Island Watson Peninsula

Coordinates: 63°32′S 56°54′W / 63.533°S 56.900°W / -63.533; -56.900

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Brown Bluff

Environment

Topography

Flora and fauna

See also

References