Introduction to the 1993 Klamath Falls, Oregon, Earthquakes

The strongest earthquakes to strike Oregon in more than 50 yrs struck the southern part of the State on September 20, 1993. These shocks, a magnitude 5.9 earthquake at 8:28 PM and a magnitude 6.0 earthquake at 10:45 PM, were the opening salvo in a swarm of earthquakes that continued for more than three months. During this period, several thousand aftershocks, many strong enough to be felt, were recorded by seismographs.