Volcano and Earthquake Hazards in the Crater Lake Region, Oregon
Landslides May Cause Large Waves on Crater Lake
Waves Generated by Earthquakes
Large waves or seiche effects caused by motion of the lake floor during an earthquake would require that the natural period of free oscillation of the lake be similar to the period of seismic waves. Surface waves responsible for motion of the lake floor would have maximum periods of about 20 seconds. The first mode of stationary oscillation of the lake is approximated by t = 2L x (g x h)-1/2 where L = length, which gives t = 4 minutes for Crater Lake, an order of magnitude longer than the maximum period of seismic waves. It is thus unlikely that earthquake shaking alone would cause dangerous waves on the lake.