Slanting Rocks of Rocky Cape
|[Note Guidelines] Photographer's Note|
|Rocky Cape National Park|
Tang Dim Mer - A Rich Heritage
The human history of Rocky Cape begins many thousands of years ago - even before Tasmania was separated from the mainland. This area would once have stood out as hills above the Bassian Plain which connected Tasmania to the mainland. Those who first came to occupy the southernmost parts of Australia over 35 000 years ago, would have traversed these hills.
Aboriginal occupation and use of this area began shortly after seas reached their current level about 10 000 years ago. The length of their association with Tang Dim Mer (one of the Aboriginal names for the area) gives it special significance to today's Aboriginal community, who maintain an ongoing presence at Rocky Cape. The area is visited frequently for cultural, spiritual and recreational purposes, and the Aboriginal community is actively involved in planning for its management.
Rocky Cape Some of the rocks here are among the oldest in Tasmania - Precambrian quartzites that are found in a broad band over much of western Tasmania. Their age has allowed time for much uplifting and folding, which has produced the often contorted patterns we see today. Those near the Rocky Cape lighthouse are typical. Since they were laid down as sandy sediments up to one billion years ago, they have experienced great changes in pressure and temperature. They have been covered by other layers of rock, deformed by major movements in the earth's crust, and in places have had molten rock forced up through them. Now revealed at the surface, these very hard rocks continue to be slowly eroded by the action of water, wind and waves.
The most spectacular erosion has taken place around the caves. These are known as sea caves because they were eroded by the sea when it was up to 20 m higher than today. Sea levels vary with the amount of ocean water held in the polar ice caps. This is dependent on climatic conditions. But the land itself can also rise or fall due to the movement of the earth's crust. The north-west coast of Tasmania is still rising very slowly.
The rocks around Rocky Cape had joints which eroded more rapidly than the surrounding rock and created caves. When sea levels dropped to where they are today, the caves were left above the shoreline, making them ideal for coastal rock shelters. North Cave is the most easily-accessible example. It is about 20 m above sea level. Try to imagine what it was like when the sea rushed into the cave. Amazingly, caves similar to these are also found beneath the sea, created by wave action when sea levels were lower.
Around Anniversary Bay there are outcrops of siltstone. They are of similar age to the more common quartzite, but were originally laid down as fine-grained silts (rather than the coarser sands that formed the quartzite.) The siltstones are so deformed and tilted that they make walking along the coastline quite difficult.
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Great Photo. I realy enjoy the contrast between the sky and orange and black of the rocks. Very interesting and informative note as well. It would have been interesting to see a photo from a bit higher up, as to include more of the ocean.
Wonderful photo, composition and technically wise! Thanks for sharing - Xplorator Radu
- [2006-01-24 15:40]
sayin Kirman..sanki kayalar boyanmis gibi ne guzel cikmis elinize saglik
- [2008-05-26 17:35]
Hello Alaettin! Great job you've done on that great shot! It's incredibly sharp and the colors are really impressive, well done my friend!
Nice contrast and compination of colours! Nice pov too!