Site 2 is really fun. Crayons and everything! At site 2 we investigate the very strange swirls in the surface of the rock. These are trace fossils of a sea floor dwelling worm called zoophycus that lived a long long time ago (Silurian) when this area was the bottom of a tropical ocean. This is not a fossil of the worm itself but of marks it left in the sediment.
The second item investigated at this site are the amazingly straight, amazingly parallel cracks in the bedrock. These are called joint cracks. They formed when the glaciers melted removing a great deal of weight from the surface of Earth. The continental ice sheets weighed so much they had pushed the crust down into the mantle. As the crust rebounded the cracks fromed from pressure unloading.
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