The sciences provide additional dimensions for interest when traveling - Geology, Botany, Zoology, Climate and Ecology being the most obvious. While crossing the seemingly endless road between Western and South Australia, the area called the Nullabor Plain on the shores of the Southern Ocean in the far south of the continent, a distance of some 2000 km, I was intrigued by the geology of the ancient limestone deposits which cover hundreds of kilometres along the Eyre Highway.
The modern shoreline (shown above) with the ocean is a dramatic limestone cliff many hundreds of kilometres long around the Great Australian Bight. The theory of continental drift proposes that the continent of Australia and the Antarctic continent were once joined in the area of the Bight, supported by the matching limestone on both continents.
There is also an ancient shoreline which is readily observed running almost parallel with the modern one, but up to fifty kilometres inland, which runs for hundreds of kilometres beside the highway. It is also a limestone cliff, but a little more weathered than the modern version. Below is a picture of the ancient shore.
The question which arises is why the land was uplifted creating a new shoreline. It may be postulated that after the Antarctic split from Australia, there was a release of weight from the southern shore of Australia, causing it to rock on the hot liquid mantle below upon which the continent floats, raising the level of the land. That phenomenon is called 'isostasy' by geologists.
A little knowledge and research of the sciences can really enhance interest in the surroundings through which one moves. :)
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