Nullarbor Plain

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NASA - Visible Earth, Nullarbor. The true Nullarbor is the light tan semi-circular area adjacent to the coast. Credit Jacques Descloitres. Image acquired by the Terra satellite on August 19, 2002

The Nullarbor Plain is part of the 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 nullus for 'nothing' or 'no one' and arbor for 'tree', and is pronounced "NULL-uh-bore" (IPA: /ˈnʌləbɔr/). It is the world's largest single piece of limestone, and occupies an area of about 200,000 km² (77,200 square miles)^[1]. At its widest point, it stretches about 1,200 km from east to west between South Australia (SA) and Western Australia (WA).

[edit] History

Historically, the Nullarbor was inhabited by the semi-nomadic Spinifex Wangai Aboriginal people. The average rainfall on the Nullarbor Plain is about 200 mm per year.

European settlers were determined to cross the plain, despite the hardships created by the nature of the Nullarbor. 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.

Eyre 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 fortuitous circumstances such as receiving some supplies from a French whaling vessel anchored at Rossiter. They completed their crossing in June 1841.

A proposed new state Auralia (meaning "land of gold") would have comprised of the Goldfields, the western portion of the Nullarbor Plains and the port town of Esperance. Its capital would have been Kalgoorlie.

The Wangai Aboriginal people were forced to abandon their homelands during the British nuclear tests 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.

[edit] Cultural significance

Road sign

'Crossing the Nullarbor', for many Australians, is a quintessential experience of the 'Australian Outback'. Stickers bought from roadhouses on the highway show 'I have crossed the Nullarbor', and can be seen on vehicles of dubious quality or capacity for long distance travel. The process of 'beating the crowds' on overbooked air services at the time of special sporting events can also see significant numbers of vehicles on the road.

Crossings in the 1950s and earlier were significant as most of the road back then was unmade dirt track. Round-Australia car trials (The Redex Trials) utilised the Nullarbor crossing for good photo shoots of cars negotiating poor tracks.

[edit] Geography

Escarpment near Eucla

The Nullarbor Plain is thought to be a former seabed. The region is also the location of Nullabor Limestone and it has a reputation as a significant karst region ^[2]

One theory is that 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 plain is a series of tiers. Each tier is flat and was formed when the sea level was much higher than it is today.^{[citation needed]}

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 Department of Environment and Conservation 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.^[3]

According to the USDA, the Nullarbor's soils are considered to be mainly Aridisols. (see map)

[edit] Climate

Rainbow over the Nullarbor Plain

The prevailing climate across the Nullarbor is typical of a desert, characterised by arid to semi-arid conditions, with maximum daytime temperatures of up to 48.5 °C (119.3 °F), although nights can see freezing conditions. The mean annual rainfall at Cook is 179.7 mm (7 inches) [1].

[edit] 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 operated for about 50 years before being superseded; relics of it are still visible.

The Trans-Australian Railway railway line crosses the Nullarbor Plain from Kalgoorlie to Port Augusta. 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, an uninhabited area noted for a water supply. 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 Indian Pacific is a regular passenger train crossing the Nullarbor from Perth to Sydney via Adelaide.

The Nullarbor Plain viewed from the Indian Pacific.

The Eyre Highway, which connects Norseman in Western Australia to Port Augusta, was carved across the continent in 1941. At first it was little more than a rough track, but was gradually sealed over the next thirty years. The last unsealed section of the Eyre Highway was finally sealed in 1976.^[4] Unlike the railway, though, it crosses the plain at its southernmost edge rather than through the centre.

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).

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 small settlements along the Eyre Highway that provide services to travellers, mostly spaced between one and two hundred kilometres apart. The town of Cook, in South Australia, was formerly a moderately thriving settlement of about 40 people, with a school and 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 four. The Tea and Sugar Train operated until 1996 supplying provisions to the town along the railway line.

[edit] Biogeography

The IBRA regions, with Nullarbor in red

Nullarbor is a biogeographic region under the Interim Biogeographic Regionalisation for Australia (IBRA).^[5][6]

[edit] Limits

Frequently The Nullarbor is expanded in tourist literature and web based material to a context of all land between Adelaide, South Australia to Perth, Western Australia^[7] - so that caution must be made as to understanding the correct limits in web based and other materials.

[edit] See also

• Nullarbor Nymph
• Great Australian Bight

[edit] References

[edit] Further reading

• Bolam, A. G. (Anthony Gladstone), 1893-1966. The trans-Australian wonderland Melbourne : Modern Printing, (many editions in the early 20th century)
• Edmonds, Jack (1976)Nullarbor crossing : with panorama photographs by Brian Gordon. Perth. West Australian Newspapers, Periodicals Division. ISBN 0909699097

[edit] External links

• Nullarbor Net
• Across The Nullarbor Travel story by Roderick Eime
• Information about crossing the Nullarbor
• Eyre Bird Observatory
• Climate charts
• History of the rail crossing
• Mundrabilla meteorite information
• Nullarbor Plain xeric shrublands (World Wildlife Fund)
• Caverns give up huge fossil haul BBC News Online, 2007-01-25. Retrieved 2007-01-25
• aerial video footage of the Nullarbor Plain
• Photo Essay on Driving Australia's Nullarbor Plain
• Governmental Biodiversity Assessment of the Nullarbor Plain