The Pinnacles
Pinnacles Desert
Situated just 17kms south of the townsite, the Pinnacles desert is the major tourist attraction of the aregion. Attracting around 250,000 visitors every year, the Pinnacles desert covers an area of approximately 190 hectares, is around 60 meters above sea level, and contains thousands of limestone Pinnacles, some up to 5 meters high. The variation in colours (due mainly to the variation in soil types), and the stark relief of the Pinnacles against a backdrop of constantly shifting sand dunes creates an eerie landscape of ever changing moods often viewed at it’s best at dawn or sunset when the shadows create remarkable patterns and shapes that ripple over the sands,
Accessible by car or tour via a fully sealed road, the sightseer is advised to allow at least 2 hours to circumvent the viewing trail and access the lookout. Entry fees to the park are $10.00 per car (pensioner discounts apply), payable at the gate. No caravans or trailers are permitted within the park, and these should be left in town or at the parking area adjacent to the access road. Pets, open fires, and camping are all prohibited within the park boundaries. Hats, sunscreen and water are essential pre-requisites for a visit to the Pinnacles, especially during the summer months.
So how did these strange pinnacles form?
The coast of Western Australia, from Shark Bay nearly to Albany, has a near continuous belt of Tamala Limestone (probably more accurately called) aerolian calcarenite - ie. wind blown calcium carbonate - which has been produced by the combination of wind, rain and the cementing agent of calcium.
A set of unique circumstances produced the pinnacles. Firstly the huge sand dunes stabilised. The rains which fell on the dunes leached down through the sand carrying the calcium. This resulted in the lower levels of the dune solidifying into a soft limestone. As this stabilisation occurred a layer of soil formed on top of the dune which allowed plants to grow and further cemented the limestone below. Gradually the lowest layer of soil, which lay between the surface and the limestone, formed into a hard cap which resulted in the old dunes having three levels - a soil and plant level near the surface, a hard cap below the surface, and a thick layer of soft limestone at the bottom of the dune.
Inevitably the roots from the plants on the top level found cracks and broke up the hard cap and the layer of soft limestone. The result was that under a surface covered with plants and soil the pinnacles developed. No one knows for sure how long ago this process occurred. It may have started as long ago as 500 000 years but equally it may only be a few thousand years old and it may still be continuing today. The Western Australian Museum has opted for some time in the last 80 000 years.
Anyway the advent of drier weather in the region resulted in the top layer of plants and soil being removed and gradually the pinnacles were exposed so that today they stand like strange sentinels on a plain of wind blown sand.
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