Nullarbor Plain
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Australia.A2002231.0145.250m_NASA_Nullarbor.jpg
The Nullarbor Plain is the vast area of flat, almost treeless, arid or semi-arid country immediately north of the Great Australian Bight. The word Nullarbor is derived from the Latin for "no trees".
It is the world's largest single piece of limestone, and occupies an area of about 200,000 sq km (77,200 sq miles). At its widest point, it stretches about 1200 km from east to west between South Australia (SA) and Western Australia (WA).
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Geography
The Nullarbor Plain is thought to be a former seabed. About 20-25 million years ago, the whole area was uplifted by crustal movements, and since then, erosion by wind and rain has smoothed out most topographic features, resulting in the extremely flat terrain across the plain today.
The southern ocean, in areas, blows through many subterranean caves resulting in blow holes up to several hundred metres from the coast. One such area open for public inspection are the Murrawijinie Caves, in South Australia. Most other caves can only be visited and viewed with conservation department approval.
Vegetation in the area is primarily low saltbush and bluebush scrub. A large part of the Nullarbor Plain is now a National Park. The Nullarbor is known for extensive meteorite deposits, which are extremely well-preserved in the arid climate. In particular, many meteorites have been discovered around Mundrabilla, some up to several tonnes in weight.
Climate
The prevailing climate across the Nullarbor is typical of a desert, characterised by extremely arid conditions, with maximum daytime temperatures of up to 48.5°C, although nights can see freezing conditions.
Contrary to popular belief, the driest spot in Australia is actually found in this region and not to the north, in the area of the Northern Territory (NT) known as the Centre. The SA settlement of Farina has average annual precipitation of 142 mm (5.6 inches); by contrast, Alice Springs, NT, receives an average of 281 mm (11.1 inches) of rain per year.
History
Historically, the Nullarbor was inhabited by the nomadic Spinifex Aboriginal people, despite the lack of surface water and land suitable for cultivation.
European settlers were determined to cross the plain, despite the hardships created by the nature of the Nullabor. Although Edward John Eyre described the Plain as "a hideous anomaly, a blot on the face of Nature, the sort of place one gets into in bad dreams", he became the first European to successfully make the crossing in 1841.
He set out from Fowler's Bay in South Australia on 17 November 1840 with John Baxter and a party of three Aboriginal men. He was forced to return to Fowlers Bay by the death of three horses due to dehydration, and made a second departure on 25 February 1841.
By 29 April, the party had reached Caiguna. Lack of supplies and water led to a mutiny, and two of the Aborigines killed Baxter and made off with the party's supplies. Eyre and the third Aborigine, Wylie, continued on their journey, surviving through bushcraft and some fortuituous circumstances such as receiving some supplies from a French whaling vessel anchored at Rossiter. They finally completed their crossing in June 1841.
The Spinifex were forced to abandon their homelands when the British began nuclear testing at Maralinga in the 1950s. Since then they have been awarded compensation and many have returned to the general area. In fact many never left. Due to their isolation it was impossible to warn them all about the testing.
Transport
The need for a communications link across the continent was the spur for the development of an east-west crossing. Once Eyre had proved that a link between South Australia and Western Australia was possible, efforts to connect them via telegraph began. In 1877, after two years of labour, the first messages were sent down the new telegraph line, boosted by a series of eight repeater stations along the way. The line was in operation for about 50 years before being superseded; relics of it are still visible.
The Indian Pacific railway line crosses the entire continent from Perth to Sydney via Adelaide. Construction of the line began in 1917, when two teams set out from Kalgoorlie in Western Australia and Port Augusta in South Australia, meeting in the centre of the Plain at Ooldea. This original line suffered severe problems with track flexing and settling in the desert sands, and journeys across the Plain were slow and arduous. The line was entirely rebuilt in 1969, as part of a project to standardise the previously disparate rail gauges in the various states, and the first crossing of the Nullarbor on the new line reached Perth on 27 February 1970.
The Eyre Highway, which goes from Norseman, WA to Port Augusta , SA, was carved across the continent in 1941. At first it was little more than a rough and ready track, but was gradually paved over the next thirty years. The last unsealed section of the Eyre Highway was finally paved in 1976.
The flatness of the terrain is such that the railway line holds the record for the longest straight section of railway in the world (478 km), while the road contains the longest straight piece of tarred road surface in Australia (146.6 km). The railway cuts straight across the Nullarbor, but the Eyre Highway cuts along the edge of the its southernmost area. Only a small portion of it is actually in the Nullarbor.
Most of the inhabited areas of the Nullarbor Plain can be found in a series of small settlements located along the railway line, and in a small hotel complex called the Nullarbor on the Eyre Highway. The town of Cook, in South Australia, was formerly a moderately thriving settlement of about 40 people, with a school and even a golf course. However, the scaling back of railway operations at the town resulted in its virtual desertion, and it now has a permanent population of just two.
One uninhabited area noted for a water supply is Ooldea, located along the railway.
External links
- Nullarbor Net (http://www.nullarbornet.com.au)
- Crossing the Nullarbor (http://www.letsgo.com/AUS/08-SouthAustralia-479)
- Across The Nullarbor (http://members.ozemail.com.au/%7Erodeime/nullarbor/) Travel story by Roderick Eime
- Information about crossing the Nullarbor (http://www.mynrma.com.au/outback_tracks_acr.asp)
- Climate charts (http://www.bom.gov.au/climate/averages/tables/cw_018106.shtml)
- History of the rail crossing (http://www.gsr.com.au/apps/media/story.php?primKeyPost=12)
- Mundrabilla meteorite information (http://spaceresearch.nasa.gov/research_projects/meteorite.html)
- Nullarbor Plain xeric shrublands (World Wildlife Fund) (http://www.worldwildlife.org/wildworld/profiles/terrestrial/aa/aa1306_full.html)de:Nullarbor-Wüste