Unit 4 Project: Dangerous and Natural Energy Earthquakes
One of the most frightening destructive forces known on earth is the earthquake. Why is the threat of an earthquake so frightening? When dealing with other destructive forces like tornados, hurricanes, and flooding, man is able to predict and track these destructive forces; therefore, providing ample warning to the population in the affected area helping to prevent the loss of life. However, an earthquake is near impossible to predict because of how one occurs. To understand how an earthquake occurs we must first understand how the earth is made. The earth is comprised of four major layers: the inner core, outer core, mantle, and crust. The crust and the top of the mantle make a thin skin covering the surface of our planet. However, this skin is not in one piece, it is actually in multiple pieces. These individual pieces are continuously moving, sliding past one another, and bumping into each other. These individual pieces of crust and mantle are called tectonic plates, and the edges of the plates are called the plate boundaries. The plate boundaries are made up of many faults. The majority of the earthquakes occur on these faults. Since the edges of the tectonic plates are rough, they become stuck on one another while the rest of the plate keeps moving. Finally, when the tectonic plate has moved far enough, the edges unstick, and the stored energy is released. The energy radiates outward from the fault in every direction in the form of seismic waves. The seismic waves shake the earth as they move through it, and this is an earthquake (Lisa Wald, 2009). When examining the hazard areas for earthquakes on the continental United States, the largest amount of seismic activity occurs along the edge of the Pacific plate and the North American plate (Henry Spall, 2009). Furthermore, there is a highly dangerous section where the two plates meet known as the Cascadia Subduction Zone. The Cascadia Subduction Zone is a 680-mile long stretch of colliding land mass that is 50 miles offshore of Oregon, Washington State, and southern British Columbia (Mason, 2008). One can see that seismic activity continues to be somewhat active moving west to east until one reaches the Rocky Mountains. The next highly active area in the continental United States is the New Madrid Seismic Zone along the Mississippi River. The New Madrid Seismic is made up of several thrust faults that stretch from Marked Tree, Arkansas to Cairo, Illinois ("New Madrid Seismic," n.d.). The final severe area for possible earthquakes is region near Charleston, South Carolina, due to the offshore faults that are thought to be capable of generating severe earthquakes ("2008 United States," 2008). I then analyzed the earthquake risk in the area I reside in. I reside in a small town in Northeastern Pennsylvania called Kingston, which is located 41.26°N 75.9°W ("Kingston Pa," n.d.). According to the U.S. Geological Survey Seismicity map, there has not been any seismic activity in my area in over a century ("Pennsylvania Seismic," 2009). Furthermore, the U.S. Geological Survey predicts there is a .08 - .10 chance of a major earthquake in my area in the next fifty years ("Pennsylvania Seismic," 2009). I continued my research concerning global earthquake activity. There is a distinctive pattern of earthquakes when looking at the U.S. Geological Survey Real-time world earthquake map. Patterns of earthquakes were found along the boundaries of the tectonic plates. There I found that there were 316 earthquakes worldwide in the past seven days with a magnitude greater than 2.5 on the Richter scale ("Real-Time Earthquake," 2012). The majority of these earthquakes occurred around the Pacific plate where it intersects with the North American Plate and the Filipino Plate. Furthermore, there was a considerable amount of activity where the Australian plate and the Eurasian plate intersect ("List of...
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