Balleny Islands

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Balleny Islands
Balleny Map.jpg
Map of the Balleny Islands
Balleny Islands is located in Antarctica
Balleny Islands
Balleny Islands
Location in Antarctica
Geography
LocationAntarctica
Coordinates66°55′S 163°45′E / 66.917°S 163.750°E / -66.917; 163.750Coordinates: 66°55′S 163°45′E / 66.917°S 163.750°E / -66.917; 163.750
ArchipelagoBalleny Islands
Area800 km2 (310 sq mi)
Highest elevation1,705 m (5,594 ft)
Highest pointBrown Peak[1][2]
Administration
Administered under the Antarctic Treaty System
Demographics
PopulationUninhabited
The Balleny Islands (top) and Antarctic coast (bottom) from space, December 2007. Dark patches are ice-free sea surface.

The Balleny Islands (66°55′S 163°45′E / 66.917°S 163.750°E / -66.917; 163.750) are a series of uninhabited islands in the Southern Ocean extending from 66°15' to 67°35'S and 162°30' to 165°00'E. The group extends for about 160 km (99 mi) in a northwest-southeast direction. The islands are heavily glaciated and of volcanic origin. Glaciers project from their slopes into the sea. The islands were formed by the so-called Balleny hotspot.

The group includes three main islands: Young, Buckle and Sturge, which lie in a line from northwest to southeast, and several smaller islets and rocks:

  • northeast of Young Island: Seal Rocks, Pillar
  • southeast of Young Island: Row Island, Borradaile Island (with Swan Base shelter hut)
  • south of Buckle Island: Scott Cone, Chinstrap Islet, Sabrina Islet (with Sabrina Refuge shelter hut), and The Monolith

The islands are part of the Ross Dependency, claimed by New Zealand (see Territorial claims in Antarctica).

Islands and rocks from north to south[edit]

Island/Rock Area Highest peak
km2 sq mi m ft
Young Island and satellite islets
Seal Rocks 0.0 0 15 49
Pillar 0.0 0 51 167
Young Island 255.4 98.6 1,340 4,400
(Freeman Peak)
Row Island 1.7 0.66 183 600
Borradaile Island 3.5 1.4 381 1,250
Beale Pinnacle 0.0 0 61 200
Buckle Island and satellite islets
Buckle Island 123.6 47.7 1,238 4,062
Scott Cone 0.0 0 31 102
Eliza Cone 0.0 0 67 220
Chinstrap Islet 0.0 0
Sabrina Island 0.2 0.077 90 300
The Monolith 0.1 0.039 79 259
Sturge Island (no satellite islets)
Sturge Island 437.4 168.9 1,705[1] or
1524[2]
5,594 or
5,000
(Brown Peak)

The islands' area totals 400 km2 (154 sq mi) and the highest point has been measured as 1,705 m (5,594 ft)[1] or approximately 1500m (5000 feet)[2] (the unclimbed Brown Peak on Sturge Island).

The Antarctic Circle is close to Borradaile Island, in the eight-kilometre channel between Young and Buckle Islands. Buckle Island and the nearby Sabrina Islet is home to several colonies of Adelie and chinstrap penguins.

Recorded human visits to the islands[edit]

The English sealing captains John Balleny and Thomas Freeman first sighted the group in 1839.[3] Balleny named the island group after himself and the individual islands after the London merchants whose financial backing had made the expedition possible. Freeman was the first person to land on any of the islands on 9 February 1839, and this was the first human landfall south of the Antarctic Circle.

Sealers sighted the islands in 1853 but did not land.[4]

In February 2015 the islands were visited for three days by the New Zealand-Australia Antarctic Ecosystems Voyage under the auspices of the New Zealand National Institute of Water and Atmospheric Research aboard the vessel RV Tangaroa, with the objective of studying marine life ecosystems of the islands, especially with reference to the humpback whale.[5] This work followed up work done on a previous visit in 2010.

On 3 February 2017, personnel from the Swiss Polar Institute's Antarctic Circumnavigation Expedition visited the islands and carried out considerable photographic and video survey work which was intended to contribute to the first accurate mapping of the main islands.[6] Most of the work was done by helicopter, although at least one landfall was also made on the islands by this expedition, using Zodiac inflatable boats.

Geology[edit]

In the archipelago, the Buckle, Sturge and Young Islands are examples of stratovolcanoes.[7] Strong earthquakes very close to the islands are rare, but tremors of moderate strength do occur over the Pacific–Antarctic Ridge, Macquarie Triple Junction and Pacific Rim between the Balleny Islands and Macquarie Island.[8] Other earthquakes occur near the Southeast Indian Ridge and Balleny Fracture Zone, including a magnitude 8.1 earthquake in 1998 that struck just over 700 km (430 mi) west-northwest of the islands[9] which changed the pattern of seismicity in a wide area around the islands.[10]

Submerged features[edit]

Several underwater features lie close to the Balleny Islands:

See also[edit]

References[edit]

  • W.E. LeMasurier; J.W. Thomson (1990). Volcanoes of the Antarctic Plate and Southern Oceans. American Geophysical Union. pp. 512 pp. ISBN 0-87590-172-7.
  1. ^ a b c Brown Peak, Composite Gazetteer of Antarctica, Scientific Committee on Antarctic Research. US source.
  2. ^ a b c Brown Peak, Composite Gazetteer of Antarctica, Scientific Committee on Antarctic Research. NZ source.
  3. ^ Gunter Faure, Teresa M. Mensing, The Transantarctic Mountains: Rocks, Ice, Meteorites and Water (Springer, 2010), 555.
  4. ^ R.K. Headland (ed.) Historical Antarctic sealing industry, Scott Polar Research Institute, University of Cambridge, 2018, p.169 ISBN 978-0-901021-26-7
  5. ^ "Balleny Islands humpback research success". National Institute of Water and Atmospheric Research. 9 February 2015. Retrieved 10 October 2019.
  6. ^ "Mapping Balleny Islands". Swiss Polar Institute Antarctic Circumnavigation Expedition. 6 February 2017. Retrieved 10 October 2019.
  7. ^ GVP, Smithsonian. "Volcanoes of Antarctica – Antarctica and South Sandwich Islands". Smithsonian Institution National Museum of Natural History Global Volcanism Program. Archived from the original on 14 May 2011. Retrieved 17 April 2011.
  8. ^ Earthquakes, USGS. "World Seismicity Maps: South Pole". United States Geological Survey. Earthquake Hazards Program. Retrieved 17 April 2011.
  9. ^ USGS. "M 8.1 – Balleny Islands region". United States Geological Survey. Retrieved 6 August 2017.
  10. ^ "Statistical analysis of seismicity in a wide region around the 1998 Mw 8.1 Balleny Islands earthquake in the Antarctic Plate". Science Direct. Retrieved 11 October 2019.