How many earthquakes occur in one year? In 1990, 16,613 earthquakes were located, says the Philadelphia Inquirer. That means scientists were able to find the epicenter, or exact location where those earthquakes occurred. In 1991, the number was similar to 1990. These are earthquakes with magnitudes of 1 to 8 on the Richter Scale. There were actually more that were smaller or unlocated.
America's 48 contiguous states have about 1,000 each year. Scientists say that they don't believe the number of earthquakes is increasing, but that more are being documented.