The Jolly's Road Crossing on the trail contains visible examples of the sedimentary quartzite/sandstone of the area.
This rock was deposited as horizontal layers of sediment approximately 750 million years ago in a shallow sea that extended from Antarctica up into Central Australia. About 500 million years ago, once the sediment had been buried by the deposition of more sediment, the rocks were rotated into the near-vertical orientation that you can see here. This rotation of the layering in the sedimentary rock is related to folding that can be seen at a much larger scale to define the shape of the Clare Valley. There is an information sign here that will assist you in answering the some of the following questions that are required to log this earthcache. You will also need to observe the exposed rock surrounding the sign.
1. Which sandstone formation is this area part of?
2. Which subgroup is the formation in?
3. What is the thickness of the sedimentary bedding (lower range and upper range)
4. Describe the colour of the sandstone visible here. There are darker siltstone beds present amongst the sandstone, estimate the width of the siltstone beds.
Please email answers to our geocaching account. You are welcome to log the cache before receiving confirmation of your answers, we will only contact you if there are any issues with your answers. Any logs without an accompanying email will be deleted.