Maine's bold coast is one of its distinctive qualities. When I first arrived in Maine, I was surprised, for I had never before seen sedimentary rocks with vertical orientation, as are many rocks along the Maine coast. It is amazing that a quick examination of a site can give you a complex geologic history of the area. For me, this meant exploring the area, and researching how each specific characteristic is formed.
Recently, I explored the Giant Stairs, an 'unusual geologic feature of the eastern side of Bailey Island.' The Giant Stairs are a rock formation that resemble a staircase, but there's nothing man-made about it. The stairs actually formed as a result of seafloor spreading. Over a long period of time, sediments had been building up, forming a crust on the ocean floor. When the seafloor spread, huge cracks were torn in the sedimentary rocks. When these breaks were made, hot magma from the earth's core rose into that crack, leaving the igneous rock we see today. Giant Stairs is a really cool feature of Maine--one that everyone should check out. It's amazing to realize that rocks and geologic features like this one are millions of years old. That is incredibly old!
Have you ever noticed the interesting orientation of the rocks along Maine's coast? To many, this looks unnatural. Sedimentary rocks originally form in the ocean as thin layers of sand or mud. Over time, these layer solidify, leaving the ocean floor as layered rock. The layers alternate between the lighter sandstone, and darker mudstone. As it lays on the ocean floor, the rocks are horizontal. The vertical orientation of the rocks are actually formed as a combined result of the sedimentation and the buckling of the ocean's crust with the formation of the Mid-Atlantic ridge (the Mid-Atlantic ridge is an undersea mountain range in the middle of the Atlantic Ocean). With the uplifting of the tectonic plates, a buckling motion occurred, forcing the sedimentary rock onto its side.
Want to know more about Maine's history? Look at the rocks and fossils around you--they'll tell you everything!
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