Tuesday's earthquake centered in Lake Erie off Mentor registered 3.1 magnitude -- relatively minor, but certainly getting the attention of Lake County residents.
Since the Ohio Seismic Network began operations in 1999, 47 quakes measuring 2-point-oh or more have been logged in Ohio, nearly matching quake activity from the previous three decades.
One explanation for more frequent quakes, says the Network's senior seismologist Michael Hansen, is constant off-shore shifting.
Michael Hansen: A lot of the stress is coming from the opening of the Atlantic Ocean, along the mid-ocean ridge. New crust is pushing North America to the west and Europe to the east at about 1 inch a year. Stress is on the whole continent. It's going to be relieved at these zones of activity.
The Ohio Department of Natural Resources studies seismic action and develops maps for quake-susceptible regions of the state for use by governments, insurance firms, and planners.
Hansen says the threat of a really big quake is quite remote, and the possibility of Tsunami action in lake Erie is infinitesimal since there's no vertical movement between plates to force water onto shores.
Rick Jackson, 90.3.