“The East Coast of the United States was shaken up by a moderate earthquake on Tuesday that was felt from Maine to Florida, Virginia to Illinois. On TV we saw people run out of buildings, thinking it might be a terrorist attack. Social media was buzzing with comments and testimonies.

Although seismologists, historians and emergency managers have recognized the potential for an earthquake along the East Coast for years, most people were caught by surprise and so responded inappropriately. The ground doesn’t shake as much in the East as it does in California, Alaska, the Pacific Northwest, Puerto Rico or the Virgin Islands. But because of the great concentration of population and infrastructure in the East, it’s an area of immense risk. “

Source: Quake a wake-up call for Eastern U.S. – CNN.com