Dr. M. A. Laskar, Assist. Professor, Department of Chemistry, Jazan University, KSA

771 views

0 likes

You will need to sign in before you can comment or like.        

   The Nullarbor Plain is the world's largest single piece of limestone. It is located on the Great Australian Bight (Southern Australia). The plain spreads over 2, 70,000 square kilometers (extending 1000 km from east to west). The plain is horizontally flat and devoid of trees. The surface of the plain has areas of depression that were formed when the surface's limestone got dissolved due to rain. One can also come across dents, which were formed after the underground caves or sinkholes had collapsed. The surface is actually a whitish, grey or brown layer of limestone or crystalline rock, which are rich in marine fossils and foraminifera (marine sediment). Beneath this surface, the actual white colored base of the plain is formed by Wilson Bluff Limestone.
   A clear view of the layers forming the great Nullarbor Plain can be observed at the face of the Bunda Cliffs, which forms its southern edge. The base (Wilson Bluff Limestone) has a thickness of 300 meters. It was a part of an ancient seabed and came into existence when Australia and Antarctica got separated 65 million years ago. The Bunda Cliffs extend for 200 kilometers and curves the Great Australian Bight. Near the bottom of Bunda Cliffs' face, one can see a white colored base formed by Wilson Bluff Limestone. The Bunda Cliffs are capped by a hardened layer of windblown sand that was laid down between 1.6 million and 1, 00,000 year ago. The height of the Cliffs ranges from 60-120 meters. This spectacular landscape may be viewed along the Eyre Highway (that links east Australia to west Australia). There are five main signed and graveled roads that reach the Cliffs. The western most cliffs offer a vantage looking point through its accessible piece of rock jutting out of the Cliff. While at the eastern end of Bunda Cliffs, at the Head of the Blight, one can catch the sight of Southern Right Whales in the ocean below the cliffs.

Comments