& LANDSCAPES ancient fossils
By Peter Bindon
When coming from the east and crossing the imaginary north-south meridian of 129°E to enter Western Australia, it seems like you are entering another land. And if it is true that it is the underlying geology which determines the surface of the landscape, this is certainly true when you enter WA from the east.
T
he traveller must first cross the remarkable Nullarbor Plain equipped with ‘Beware of Camels’ signs and its famed treeless expanse which at first seems a great mystery but is easily explained by an almost complete lack of available water for trees - or travellers for that matter. If you take a short walk almost anywhere on its flat surface, you are bound to discover that you are walking over a limestone landscape which was submerged beneath the ocean until relatively recently geologically speaking. This is demonstrated by an
abundance of marine fossil shells which are readily recognisable as almost identical to those found on modern seashores. Beneath the waterless surface, the plain is host to numerous limestone caves that penetrate deep into the interior of the plain. Most are above current sea-level and so are never flooded with salty water. In these there are reserves of fresh water that has accumulated over many years and which supply fresh water to the scattered grazing properties and infrequent roadhouses providing motorists with necessities and an occasional change of scenery. Travelling further into the state via the Eyre Highway it takes quite some time to encounter landscape features that are distinctive to Western Australia, but once you approach the Greenstone Belt it is clear that you are in a very ancient land. This is a part of WA where huge granite ‘domes’ project upwards through the surface of the plain interrupting the flat
The treeless expanse that is the Nullarbor Plain.
Western 4W Driver #121 |
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