Seymour Island

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For Baltra Island, also called South Seymour Island, in the Galápagos Islands group, see: Baltra Island.

For North Seymour Island in the Galápagos Islands group, see: North Seymour Island.

Seymour Island is an island in the chain of 16 major islands around the tip of the Graham Land on the Antarctic Peninsula. Within the island chain, it is located off the north tip of Snow Hill Island and just of east of the larger James Ross Island and it's miniscule neighboring island, Lockyer Island.

Seymour Island is sometimes called Marambio Island or Seymour-Marambio Island, taking its resident Argentine base as its namesake (see section, Base Antárctica Marambio, below).

Contents 1 Base Antárctica Marambio 2 Climate 3 Paleontological Significance 4 References

[edit] Base Antárctica Marambio

Seymour Island is the site of Base Antárctica Marambio, Argentina's main base in Antarctica. The base is situated at the following coordinates: 64°14′S, 56°37′W.

The base is fully equipped year round to support its crew members, who are the only human inhabitants of the Island.^[1] The site has 27 buildings in a total area of 4,278 m². There is a medical facility equipped with x-ray machines and an on-call doctor and three paramedics. The base is powered by four generators and 492,000 liters of Arctic gas-oil for transportation. There is also a sewage treatment plant.^[2]

Prior to the founding of the base on October 29, 1969, Seymour Island was the site of an important logistical achievement in Antarctic exploration: Argentine Vice-Commodore Mario Luis Olezza built the Antarctic continent's first airplane runway (with the dimensions of 1200m [3800ft] long and 40m [120ft] wide) on the Island. The track has since been modernized with electronic landing systems and radio and electronic beacons.^[3]

The base's primary purposes are scientific. The scientists stationed at the base observe cosmic rays, glaciology, ionospheric properties, auroras and meteorology, in addition to monitoring stratospheric ozone.^[4]

In winter the base has an average of 55 crew members, but in summer the population of the base can grow to 150.^[5]

Seymour Island and the Base Marambio is approximately 100 km (88 mi) from Argentina's other major base in the area, Esperanza Base ( 63°24′S, 56°59′W), located in Hope Bay, which is at the tip of the Antarctic Peninsula. Base Marambio is northeast of the area's third Argentine base, General Belgrano II ( 77°52′S, 34°37′W), which is located on the Antarctic coast at the eastern base of the Antarctic Peninsula, in the south Weddell Sea.

[edit] Climate

The average temperatures on Seymour Island, as measured at Base Antárctica Marambio, are 1 °C during the summer and −21 °C during the winter. In the wintertime, however, strong winds can lower the wind chill temperature as low as −60 °C.^[6]

[edit] Paleontological Significance

In November 1892, when Norwegian mariner Captain Carl Anton Larsen landed his ship, the Jason, on Seymour Island, he returned with more than maps of the territory; he found fossils of long-extinct species. (Interestingly, Larsen's trip aboard the Jason was significantly more successful than his Swedish Antarctic Expedition journey between 1901 and 1904. During that trip, his ship, the Antarctic, was crushed and sunk by icebergs, and he and his crew were forced to weather fourteen months on the neighboring Snow Hill Island, surviving on penguins and seals.) Ever since his voyage on the Jason, the island has been the subject of paleontological study.

Seymour Island has been the site of much study of the Eocene period of climactic cooling, a process that culminated in the initiation of Antarctic glaciation. Studies of the fine fraction carbonate from sites in the Southern Ocean suggest that, rather than a monotonic decrease in temperature over the Eocene period, the middle of the epoch was punctuated by a brief duration of warming (Bohaty and Zachos, 2003).^[7]

Seymor Island has been a site of study of many fossils from this particular part of the Eocene period, during which there was a more flourishing ecosystem with diverse biota as a result of the warmer climate. A diverse array of fossilized species have been studied on the Island, including extinct penguin species (such as Palaeeudyptes klekowskii and Archaeospheniscus wimani), various species in the bivalvia class and various types of flora and fauna.^[8]

[edit] References

1. ^ http://www.answers.com/topic/marambio-base
2. ^ http://www.answers.com/topic/marambio-base
3. ^ http://www.answers.com/topic/marambio-base
4. ^ http://www.answers.com/topic/marambio-base
5. ^ http://www.answers.com/topic/marambio-base
6. ^ http://www.answers.com/topic/marambio-base
7. ^ http://gsa.confex.com/gsa/2005AM/finalprogram/abstract_96130.htm
8. ^ http://gsa.confex.com/gsa/2005AM/finalprogram/abstract_96130.htm