New York City and Manhattan Schist Essay

Rock the House. Although New York City is known around the world for its manmade wonders, a question that one asks themselves is how Manhattan came to be, and the answer is Bedrock. Bedrock is a solid rock below the loose surface of a material. It's a solid rock that makes up the earth's crust, it's found underneath surface deposits of soil. It is the solid rock beneath loose deposits like soil or alluvium, and is usually unweathered. Their are also three processes by which bedrock is formed. Igneous bedrock formation when lave solidifies. Sedimentary bedrock which forms when layers and layers of sediments compress and the deepest layer turns into solid sheets, and finally Metamorphic bedrocks which are formed when either sedimentary or igneous rock layers change as a result of environmental factors like extreme pressure or heat. The Bedrock that is found in New York City ranges from1.1 billion-190 million years old. As Bedrock as an anchor the island of Manhattan was build on three strata which is a layer of material that is naturally or artificially formed often formed one upon another known as Manhattan Schist, Inwood Marble and Fordham Gneiss. Inwood Marble is a marble that is found by a majority of rivers such as Harlem and the East. Fordham Gneiss came first and was formed 1.1 billion years ago in the pre- Cambria era. This was an era were the continent of North America layer in a barrow basin beneath the sea which was shallow. Sand and Silt had been accumulating in the basin forming the sedimentary rock. When a continental shirt occurred a landmass collided with North America and hit the sedimentary rock upward and formed a mountain range. The reaction from the collision and high pressure caused the rock to recrystallize and formed a black and white metamorphic rock which is what we see today. The Fordham Gneiss is found along the west side in Riverdale, and along the east side in Fordham, and north into Van Cortlandt Park. Gneiss is also found on Roosevelt Island, emerging from the East River, and in Long Island City, and Queens. Then came the Schist which was formed about 450 years ago, which means that its the oldest of New York's bedrocks after Fordham Gneiss.The Schist is known in Manhattan's as it's spine because it dips abruptly several hundred feet, below group at the Washington Square and then an ascent begins at Chamber Street, "these dips and rises account for the gap between “midtown” and “downtown” in the Manhattan skyline. Since

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