This is an EarthCache and has special requirements for logging it. You cannot log a Found It without responding to the logging requirements set out below.
Only one find claim per Message. Each Geocacher claiming a find must submit an individual response. One team can not lodge a response on behalf of a group of people.
Now here is an interesting curiosity.
You are looking at a monument commemorating the Indigenous Light Horsemen who served in conflicts in which Australia has been involved. You can read more about it HERE.
We have all seen the ubiquitous sandstone monument like this one, before, so what is different geologically, about this one?
The answer is in its colour and layering.
Sandstone can exhibit many colours, but what paints the sandstone such rich colours? Why is there a dominant colour?
Well, most sandstone originates in granite - a type of igneous rock with minerals that contain some iron. But these minerals are mostly green or dark brown. When the rock breaks down in weathering, it produces sand grains that later make up sandstone. The weathering process is mostly chemical: it happens when water comes into contact with the atmosphere and absorbs oxygen: it then removes electrons from the iron to produce haematite (oxidized iron, somewhat like rust - when you leave a tin geocache out in the weather for a couple of years). The quartz sand grains from the weathered granite end up with a very thin, paint-like coating of hematite on them, and it's the iron in hematite (it has lost three electrons, remember) which absorbs most of the visible colours of light so you see only red.
When it comes to Layers, they are also called strata so we are now talking about Stratigraphy and The Law of Original Horizontality, first proposed by Danish geological pioneer Nicholas Steno in the 17th century. The law states that layers of sediment were originally deposited horizontally under the action of gravity. Any rock layers that are now folded and tilted have since been altered by later outside forces. This is a fundamental law in geology, apparently.
So how do layers become circular?
It’s to do with the phenomenon of Liesegang ring patterns. These happen during the physical and chemical changes occurring during the conversion of sediment to sedimentary rock (diagenesis) or maybe even later, by a “rhythmic precipitation” (maybe think about that one!), often controlled by fissures and cracks in the rocks which act as conduits for the chemical solutions. The rock is over-saturated with regard to some chemical compounds. The rings may be different in the chemical composition (by quality) and/or show a gradual change (by quantity) in special compounds like goethite - a widespread iron oxide mineral – again, the colouring. Sometimes they form around a nucleus or start off from a rim.
But, according to the Wiki, the precise mechanism from which Liesegang rings form is not entirely known and is still under research.
Not much chance then for "amateur budding-geocaching geologists" to understand it all. Just remember when you see rings like these again (and you will), that they are this "Liesegang ring pattern" phenomenon.
Still, it begs the question, and if this earthcache gets you thinking and later, researching, as much as it has done for us, then it is indeed a worthwhile earthcache to visit.
To claim your find for this earthcache,
1. describe what you see on the lower, western (highway) side of the sandstone face - the face without any plaques on it (texture, colour, layers, etc).
2. Give a simple explanation for what you see.
3. Take of photo of yourself OR your GPS to show a view of GZ. Include it in your message, but please do not post it in your log, it might give too much away.
When you have your response to the above, please, if possible, MESSAGE us, using the link at the top of the page underneath the name of the Cache. We prefer the MESSAGE method, as apparently we don't respond to emails very well, but messages we do. We will contact you by MESSAGE once your MESSAGE has been received. But you can log your find in the meantime, and just say that you have MESSAGED your answers to the COs.
As a footnote, this sandstone, we have been told by the local RSL Sub-Branch, comes from Helidon in Queensland. The sandstone which comes from the [name removed] Quarry, comprises hard and massive, predominantly fine to coarse grained sandstone, and varies in colours from caramel browns, salt and pepper, lavender to pink and white stone. [This] sandstone is a hard stone mined in the Helidon region of Southern Queensland. The sandstone from the quarry, is not layered in bands as is most sedimentary rock, but in swirls and circles. This natural rock formation and colour allows this quarry to have a competitive advantage over other suppliers of sandstone, even those on the other side of the hill at Helidon. The colour is sought after for many end-uses including cladding on up-market residential developments in China. The stone is ideal for use in building as blocks, tiles, pavers, landscape, complex and simple profiling, sculpting and aggregate. Two computer controlled wire saws are in operation.
Happy Earthcaching!