Crossing The Nullarbor

Thursday 5^th April 2012......

Crossing the Nullarbor on the Eyre Highway stretches 1,208klms from Ceduna in SA to Norseman in WA. The Nullarbor Plains unravels across the foot of Australia........across the Great Australian Bight.

The Great Australian Bight in the Southern Ocean houses the Great Australian Bight Marine Park. This park was established in 1998 to protect the breeding grounds of the Southern Right Whale, the only mainland breeding sites of the Australian Sea Lion and the unique seabed flora and fauna of the Bight.

At The Head of the Bight, 78klms west of Yalata in the Yalata Indigenous Protected Area, a mass of sandhills climbs into Bunda Cliffs.....a fortress of rock that stretches some 200klms to the WA border. From May to October this is one of Australia's best sites for whale watching as the Southern Right Whales come to the shallow waters for breeding.

The Bunda Cliffs, from its cliff edge at The Great Australian Bight, stretches back inland forming the Bunda Plateau which supports the expanse of land known as The Nullarbor Plains, the largest limestone plateau (karst) of its kind in the world. The cliff face ranges in height from 40 to 80 metres and stretches west for 800klms.

There are three distinct units of limestone. The light coloured base, Wilson Bluff Limestone, formed when sea levels were higher and the Southern Ocean inundated South Australia. The next cliff layer is the Nullarbor Limestone which began forming 25 million years ago. The cliffs are capped by the Bridgewater Formation, formed between 1.6 million and 100,000 years ago. It consists of a hardened layer of windblown calcareous sand.