Billy Goat Trail

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  • Topic: Plate tectonics, Sedimentary rock, Granite
  • Pages : 3 (998 words )
  • Download(s) : 175
  • Published : September 22, 2011
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Billy Goat Trail
The Billy Goat trail currently located in Maryland and is part of the Great Falls. After getting familiar with the Billy Goat Trail you can see all the evidence that a great geological phenomenon has occurred at that location. This location went through several geographical changes that I will be mentioning along with some of the evidence from the Billy Goat Trail.

The Billy Goat Trail actually started at the bottom of the Iaptus Ocean more than 460 million years ago. At the bottom of the ocean the sand was being deposited on top of the mud making some graded bedding that was caused by turbidity currents. The rock that was being formed from graded bedding on the bottom of the ocean floor was the sedimentary rock called Greywacke. At about 460 million years ago the Iaptus Ocean started to disappear because the movement of the tectonic plates caused a group of volcanic arcs to collide against North America called the Tocanian Orogeny. This collision made a subduction zone where the massive oceanic crust was pushed below the continental crust causing high pressure and low heat to the rocks being scraped as the oceanic crust was subducted called the accretionary wedge. The accretionary wedge was made up of Greywacke turning to Meta-Greywacke cause of the exposure to heat and high pressure. The evidence that we saw at the Billy Goat Trail was that the rock Meta-Greywacke was the dominant rock found. Also the Meta-Greywacke rocks had some folding on them indicating the high pressure it must have been under. Another observation I made was that we saw an igneous rock called Migmatite, which is basically a rock that was left in a partial melting state. The rock was leaking out granite magma cause of the heat it was under but the heat didn’t last enough for the rock to complete its transformation so it cooled down and was stuck in partial melting.(1) After the Tocanian Orogeny there was another large mass of land that was coming towards the region...
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