Wrong.
Yes, California and Alaska have the most number of earthquakes in the United States, but they are not the only locations where earthquakes can occur. (Check out the USGS website for maps showing locations of large historical earthquakes in the United States.) Devastating earthquakes have occurred in historic times in Missouri and South Carolina. In fact, every state in the United States has experienced an earthquake at some point during the history of European settlers. Many of these earthquakes are considered light to moderate, with approximate magnitudes between 3 and 5, but their locations and the style of architecture in the Midwest and East often result in large areas being damaged.
We all know about the hazard of earthquakes in California; the state experiences many minor earthquakes every year and major earthquakes occur ever few decades. Earthquakes in the rest of the United States (at least east of the Rocky Mountains) are much less common, yet when they do happen can be more damaging. So how do you know if you live in a high-risk area for earthquakes? And if you do, how worried should you be about an earthquake?
The United States Geological Survey (USGS) makes available maps and other data available that shows the probability of earthquakes hazards in the United States. The hazard maps measure the probability of exceedance (PE) for different ground motion effects over time. The ground motion effect (PGA) is measured in %G, or the percent of acceleration of gravity. (G, or the force of gravity is measured as 9.78 m/s2. During an earthquake forces caused by the ground shaking are measured as a percentage of G.) Another hazard measured by the USGS is the spectral acceleration (SA) expereinced for buildings. All of these hazards are used to determine what will happen to buildings and other structures during an earthquake.
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