You will be able to park on the wide shoulder of 446 at this location where a roadcut has exposed the bedrock. You should be able to find an example of rock spalling which is what you will learn about for this earthcache.
This roadcut that you are looking at is cool for another reason. For this area, you would expect the bedrock to be sandstone as part of the Edwardsville formation. But if you examine it closely, you will notice that this rock is limestone. But this area is not a bioherm which creates a small pocket of limestone. What you see in front of you is the layer of Ramp Creek Limestone, which lies on top of the Edwardsville formation It's the first layer of the Sanders group which formed during the transition time as this area was going from delta to a shallow sea. When this rock was being laid down, Indiana was in a restricted coastal lagoon environment.
As you look as this section of limestone, you should notice a section of spalling. So what is spalling? Spalling can occur for different reasons. The primary reason is moisture migrates from the slab and gets trapped under the surface trying to evaporate out. This creates hydrostatic pressure under the surface and it is this pressure that causes the stone to break to release the moisture pressure. You can see that the rock is peeling away from itself.
Fossil collecting is allowed at this site. If you find something and don't know what it is, I can help identify it.
To get credit for this earthcache, send answers to the following to my account:
1. Estimate the size of the spalling section in the limestone.
2. Why is this section falling away?
3. What is the name of this limestone?
4. Why is there limestone here instead of sandstone?
5. Post a picture of yourself (face not required) or a personal item at the roadcut.