Converging Plates; The Appalachian Mountians by McKayla Hamilton

My travels this week took me to the Appalachian Mountains which are an ancient mountain range that extends throughout the Eastern US and into southern Canada. These mountains are approximately 480 million years old, and before erosion took it's toll, they stood as tall as the Alps! This mountain range formed by collision of plates during the construction of Pangea. The mountains continued to grow higher with the collision of each portion of land that would be forced together and become the super-continent of Pangea. There were three "steps", so to speak, of the mountain building process of this range, and each of these plate collisions caused further rock deformation and growth. The earliest collision that started the growth of the Appalachians happened when the oceanic plate Ipateus collided and subducted under the North American Craton. Thrust faulting of this subduction zone lifted and warped the rock, causing the mountain to rise. Like I mentioned, these mountains were formed on a thrust fault, which is the result of compressional stress that causes horizontal shortening but vertical thickening of the crust. A common result of this type of fault compression is folded rock that is present in the Appalachians and pictured below. The Appalachians have since stopped growing, but they are nevertheless breathtaking and still a perfect example of what can happen when two plates collide.