Site 4 Head of Falls and Two Cent Bridge Trail Waterville Formation Under the Kennebec
Greetings Geology and Trail Fans.
As you cross the famous Waterville Two Cent Bridge you have an opportunity to observe Central Maine’s bedrock, famously known as the Waterville Formation. On the East (Winslow) end of the bridge, facing the south side of the bridge, look straight down to the bank of the Kennebec River. Unless the water is very high you will get a peak on this bank of the river at the bedrock that underlies Central Maine from Manchester in the Southwest to LaGrange in the Northeast.
This primarily slate rock formed under ancient oceans in horizontal layers of sediment that compressed and hardened into sedimentary rock. Movements of the earth’s crustal plates pushed these rocks together under great heat and pressure, folding and uplifting them and changing them into metamorphic slate. Evidence of this folding is visible in the ledge that you see below. Folds called isoclines can be seen on the southern edge of this outcrop (the “top” from your perspective as you look down) These folds are small and tightly folded. Note that folds in rocks can occur at a great range of sizes – from a few inches to thousand of feet in size.
