Each year the southern California area has about 10,000 earthquakes. Most of them are so small that they are not felt. Only several hundred are greater than magnitude 3.0, and only about 15-20 are greater than magnitude 4.0.
From 1975-1995 there were only four states that did not have any earthquakes. They were: Florida, Iowa, North Dakota, and Wisconsin.
The second-largest earthquake ever recorded struck Alaska’s Prince William Sound in 1964. The magnitude 9.2 quake killed 128 people, most by the resulting tsunami. In some places, the ground was uplifted almost 38 feet, and in others it dropped more than seven feet. The tsunami reached heights of around 220 feet locally, and killed 11 people 1,650 miles away in Crescent City, California.