Site 4: Potholes

Wow, now this is a cool site. Check out these sweet potholes.
Not potholes like you see on the street, not even related. These potholes are formed when scouring stones are swirled by the water slowly grinding and polishing a hole into the rock.

















We even have you folks practice making a pothole of your own. Good Luck!



Two things change dramatically at this site. The bedrock changes from the dolostone below to Limestone. This can be seen in the rounder and smoother shaping of the rock due to increased chemical weathering, and the gradient of the stream increases quite a bit.

Speaking of gradient we do another Jakestick activity here to measure the stream gradient. Gradient is important because it is what gives the water a greater velocity and more kinetic energy to create features such as potholes.

As an aside, across the stream under a tree, I like to refer to as the "tree of life", a good deal of water is pouring out. This is a very small cave. The water is runoff from upstream that has run into a joint crack to a joint cave. wha? check the video and see site 2 for information about joint cracks.