At this location you can see coarse grained quartzite that was originally deposited in a high energy, shallow marine environment. This occurred around 750 million years ago. The layering that occurred is called sedimentary bedding. You can see evidence of the marine bed in the rocks here, with some layers preserving the ripples that are similar to what you see in the sand at the beach.
However, this is not the feature you are looking closely at here.
Rocks in this area have been folded, causing the layers to be tilted. Fractures have occurred, and these are near vertical - this is what makes this area excellent for grape growing. The fractures allow water to drip down into the ground water. Plant roots are also able to grow down through these fractures to access the ground water.
You can see smooth quartz veins in the rock here and this is what you need to observe to answer questions to claim this earthcache.
These lines indicate that a slab of rock that once lay above what you can see now slid over this rock, forming these striations in the quartz. These lines are oriented approximately east-west.
You will need to answer the following questions regarding these quartz veins. There is an information sign at GZ that will assist you with some answers.
1. What do geologists call these smooth quartz veins?
2. How long ago were the rocks in this area folded?
3. Directly behind the information sign is an example of one of these veins. Estimate the width of the vein.
4. Just to the right of the sign, behind a tree, is another example. How does this vein differ from the first?
Email your answers to claim a find on this earthcache. You are welcome to log the cache after you have submitted your answers - we will only contact you if there is an issue with your answers.