James Ross Island

James Ross Island is a large island off the southeast side and near the northeastern extremity of the Antarctic Peninsula, from which it is separated by Prince Gustav Channel. Rising to 1,630 metres (5,350 ft), it is irregularly shaped and extends 64 km (40 miles) in a north–south direction. It was charted in October 1903 by the Swedish Antarctic Expedition under Otto Nordenskiöld, who named it for Sir James Clark Ross, the leader of a British expedition to this area in 1842 that discovered and roughly charted a number of points along the eastern side of the island. The style, "James" Ross Island is used to avoid confusion with the more widely known Ross Island in McMurdo Sound.[1]

James Ross
Map of Graham Land, showing James Ross Island (2)
James Ross
James Ross Island (Antarctic Peninsula)
Geography
LocationAntarctica
Coordinates64°10′S 57°45′W
ArchipelagoJames Ross Island group
Area2,598 km2 (1,003 sq mi)
Length64 km (39.8 mi)
Highest elevation1,630 m (5350 ft)
Highest pointMount Haddington
Administration
Administered under the Antarctic Treaty System

It is one of several islands around the peninsula known as Graham Land, which is closer to South America than any other part of that continent.[2]

The island was connected to the Antarctic mainland by an ice shelf until 1995, when the ice shelf collapsed, making the Prince Gustav Channel passable for the first time.[3]

Mendel Polar Station, the first Czech Antarctic Base, is located on the island.

Paleontology

Two dinosaur-bearing formations are present on the island, both from the Upper Cretaceous: the Santa Marta Formation and the Snow Hill Island Formation. These are two of only three known formations to have dinosaur fossils in Antarctica.

The first dinosaur discovered in Antarctica was Antarctopelta oliveroi, a medium-sized ankylosaur found on James Ross Island by Argentinian geologists Eduardo Olivero and Roberto Scasso in 1986. The dinosaur was recovered from the Campanian stage of the Upper Cretaceous Santa Marta Formation, about 2 km (1.2 mi) south of Santa Marta Cove on the north part of the island. The ankylosaur was not formally named until 2006.[4]

James Ross Island from NASA's DC-8 aircraft during an AirSAR 2004 mission over the Antarctic Peninsula

In December 2003, U.S. paleontologist Judd Case from Saint Mary's College of California and U.S. geologist James Martin from the South Dakota School of Mines & Technology discovered the bones of a theropod dinosaur on the island. Nicknamed "Naze" after the northerly Naze Peninsula on which it was found, the Late Cretaceous remains include an upper jaw and teeth, and most of the lower legs and feet. Little information is available, but the shape of the leg and feet indicate it was a runner. In 2019, it was given the name Imperobator antarcticus. It was large, about the size of Utahraptor. It is the second Antarctic theropod discovered, after Cryolophosaurus.[5]

An ornithopod was found in the Snow Hill Island Formation by Argentine paleontologists Rodolfo Aníbal Coria and Juan José Moly in 2008. In 2013, Coria named it Trinisaura santamartaensis.[6]

In 2015, an iguanodontid found in 2002 by Fernando Novas[7] was named Morrosaurus antarcticus by Sebastian Rozadilla, Federico Lisandro Agnolin, Fernando Emilio Novas, Alexis Rolando Aranciaga Mauro, Matthew J. Motta, Juan Manuel Lirio Marcelo and Pablo Isasi. The genus name refers to the site of El Morro on James Ross Island, where the remains of the species were found. The specific name refers to Antarctica.[8]

Named features

James Ross Island features several features named by various surveying and exploration groups.

See also

References

  1. "James Ross Island". Geographic Names Information System. United States Geological Survey. Retrieved 2012-07-16.
  2. ESA Science & Technology: Graham Land
  3. Rubin, Jeff (2008). Antarctica, p. 276. Lonely Planet.
  4. Salgado, L.; Gasparini, Z. (2006). "Reappraisal of an ankylosaurian dinosaur from the Upper Cretaceous of James Ross Island (Antarctica)". Geodiversitas. 28 (1): 119–135.
  5. "A Lost World: Two Previously Unknown Dinosaurs Discovered in Antarctica". Maryland VIP K-16 Grant. Science Inquiry. Archived from the original on 2007-09-29. Retrieved 2007-04-04.
  6. Coria, R. A.; Moly, J. J.; Reguero, M.; Santillana, S.; Marenssi, S. (2013). "A new ornithopod (Dinosauria; Ornithischia) from Antarctica". Cretaceous Research. 41: 186–193. doi:10.1016/j.cretres.2012.12.004.
  7. Novas, F.E., A.V. Cambiaso, J. Lirio, & H. Núñez, 2002, "Paleobiogeografía de los dinosaurios cretácicos polares de Gondwana", Ameghiniana (Resúmenes) 39(4): 15R
  8. Rozadilla, Sebastián; Agnolin, Federico L.; Novas, Fernando E.; Aranciaga Rolando, Alexis M.; Motta, Matías J.; Lirio, Juan M.; Isasi, Marcelo P. (2016). "A new ornithopod (Dinosauria, Ornithischia) from the Upper Cretaceous of Antarctica and its palaeobiogeographical implications". Cretaceous Research. 57: 311–324. doi:10.1016/j.cretres.2015.09.009.
  9. "Brandy Bay". Geographic Names Information System. United States Geological Survey. Retrieved 2011-08-19.
  10. "Rohss Bay". Geographic Names Information System. United States Geological Survey. Retrieved 2018-08-03.
  11. "Sharp Valley". Geographic Names Information System. United States Geological Survey. Retrieved 2018-07-27.
  12. "Stoneley Point". Geographic Names Information System. United States Geological Survey. Retrieved 2018-08-03.

 This article incorporates public domain material from the United States Geological Survey document: "James Ross Island". (content from the Geographic Names Information System)

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