Danger Below: Earthquake
Sheleana Hornback
August 26, 2012
Kaplan University
SC300
Danger Below 2 One of the most frightening and dangerous natural disasters known to man are earthquakes. Why is the threat of an earthquake so frightening? When dealing with other natural disasters like tornados, hurricanes, and flooding man is able to predict and track them: therefore, providing ample warning to people in the affected area. Earthquakes on the other hand are nearly impossible to predict because of how they occur. To understand how an earthquake occurs we must first look at how the earth is made. The earth is composed 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 the earth. This skin is multiple pieces and is constantly moving, sliding past each other, and bumping into each other. These pieces are called tectonic plates and the edges of these plates are called the plate boundaries. Most earthquakes occur on these faults.
The edges of the tectonic plates are rough and they become stuck on the one another while the rest of the plate keeps moving. When the tectonic plate moves far enough the edges unstick and the stored energy is released. The energy radiates outward from the fault in all directions in the form of seismic waves. The seismic waves shake the earth as they move through it causing an earthquake. (Wald, nd) During researching earthquake patterns across the United States I noticed that most of the earthquakes are located along the western shorelines of California. These earthquakes occur along the pacific coast and continue southward along the Pacific coast and north along the Pacific coast. Danger Below 3 I live in
