This query concerns a series of rock formations on a rock platform at Elvina, an hour's drive north of Sydney, Australia. I am researching Australian indigenous rock art and these formations may have a significance in relation to the engraved rock art which is profusely scattered over this platform.
If these forms are natural features it could be that some rock art was drawn in their vicinity due to a meaning that may have been known to the artists of the time. If, as we suspect, these marks were made by people's fires over the last few thousand years they could have a different significance—perhaps a ritual one. Possibly they may have been formed by fires as a part of ritual initiation and would have been lit in the same place every 10 to 15 years, which was the average interval between initiation ceremonies some 100 miles north and south of this site.
Ethnography is very sparse in this area as smallpox wiped out the indigenous people shortly after colonisation in 1788. This precluded the European collection of information and the passing on of the associated stories among the indigenous peoples.
We, at the moment, call them 'snames', a meaningless term (perhaps a contraction of 'whatsisname') which is used by us to avoid any unsubstantiated assumptions. They are dish-like depressions in fine Triassic Period current-bedded tessellated sandstone near the Hawkesbury River.
This rock platform has many features that are belived to be natural formations and tend to lead an observer to believe that anything that is not obviously the work of a human hand must be a natural feature. This, I believe, is the reason that snames have never, to date, been mentioned in the literature. The black circles are snames. If our suppositions are correct the management and understanding of the associated rock art may be revised.
The following two images could be the beginning of a sname. Some force, possibly fire, has affected the surface of the sandstone to a depth of about 8mm and the centre has eroded away. The first image has a chain layed around the vanished flake on a line where tapping the rock surface with the knuckles results in a change in the sound produced from a drumming to a solid note. The second image is taken with the chain removed. Click to enlarge.
These next two images (from another location) show the effect of the recent burning of a quantity of dry hardwood on sandstone. What you see is the result of an observation walkway being burnt by a bushfire. A section of the walkway has been completely destroyed and natural events ( wind or rain or both) have removed all trace of ash and charcoal, leaving little evidence as to the cause of the flaking. The iron spikes that had attached the walkway to the rock appear to have had little effect on the sandstone as the flaking is restricted to the area directly beneath the walkway. It would appear that heat applied to the rock surface has had the effect shown. Note the tessalations on the left image. Click to enlarge.
This image illustrates the use of natural elements in an engraving. The cross lines are engraved between two tessellated lines to form a ladder like image. Click to enlarge.
A recently constructed road has cut through the southern end of the rock platform. The sandstone lense (a palaeochannel, once part of a river delta) that forms this platform can be clearly seen in the next two images. Click to enlarge.
So this is our problem. I lack the expertise in the field of geomorphology to proceed further than to establish the undoubted link between the engravings and the snames. Any advice you could offer or referrals to others who may have struck a like problem would be greatly appreciated. There will undoubtly be other information that might help, do not hesitate to ask and if it is within my power I will obtain and forward it to you.
The location of this site. Click to enlarge.
Map of Elvina rock platform. Click to enlarge.
Some views of parts of this tessellated rock platform. The red and white scale is 0.5 metres long. Click to enlarge.
Some pits of various sizes that are believed to have occurred naturally, there are thousands of these. These do not appear to have a form similar to cupules. Click to enlarge.
Some examples of gnammas which occur but rarely on the platform. Click to enlarge.
These are some examples of snames which occur frequently and are mostly in association with a certain type of engraving. Click to enlarge.
This image is possibly a sname. I feel it is not a gnamma as its size would indicate a sname rather than a gnamma at this location. It has been filled with vegetation. Click to enlarge.
The next two images are a stereo pair. When viewed stereoscopically a dip can be seen in the centre, possibly a sname.
THANK YOU
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