OHIO OUTDOOR NOTEBOOK
By Laura Jones, Ohio Department of Natural Resources
Ohio is no stranger to the shake, rattle and roll of earthquakes
Ever felt the earth move under your feet, but just thought it was your imagination or a passing truck on the street? Well, next time, think twice and consider that it just might have been an earthquake!
Here in Ohio, you ask? Yes, just talk to residents living in the northeast corner of the state who have experienced several small earthquakes in the past few years. While most of our earthquakes go unnoticed and cause no damage, our state is susceptible to seismic activity, largely due to faults located in western and northeast Ohio.
Over the last two hundred years, the Buckeye State has experienced more than 170 earthquakes of a 2.0-magnitude or higher. In fact, western Ohio is the second most active earthquake zone in the Midwest, according to Michael Hansen, senior geologist with the Ohio Department of Natural Resources (ODNR) and coordinator of the Ohio Seismic Network.
The largest earthquake known to have originated within Ohio's borders occurred on March 9, 1937, in western Ohio's Shelby County measuring 5.4 in magnitude. Residents in the town of Anna reported tipped chimneys, twisted church organ pipes and a school building damaged so badly it had to be torn down.
Fifteen of Ohios 170 earthquakes have caused damage, most of which was minor. In addition to the 5.4 Anna earthquake here are some of the other heavy-hitters to shake our state:
- 5.0 on Jan. 31, 1986, in Painesville, Lake County
- 4.9 on March 2, 1937, in Anna, Shelby County
- 4.8 on Sept. 19, 1884, in Lima, Allen County
- 4.5 on July 12, 1986 in St. Marys, Auglaize County
The most active seismic area in the state is focused in the neighboring counties of Shelby and Auglaize, which have been the epicenter for more than 40 earthquakes since 1875. Other areas prone to getting the shakes include northeastern and southwestern Ohio.
So what causes an earthquake? Below the earths surface, giant blocks of rock move against each other. When they collide or slip past each other, they create waves of seismic energy that travels through the ground causing vibrations that lead to an earthquake. Ohios most recent quake to cause damage (though minor) occurred on January 26, 2001 in the northeastern portion of the state. Residents of Ashtabula and surrounding communities felt an earthquake with a magnitude of 4.5.
Did you know that one of the largest quakes to shake the lower 50 states happened in New Madrid, Missouri in the early 1800s? It was so powerful the seismic effects were felt some 330 miles away in Cincinnati, where chimneys were toppled.
The Ohio Seismic Network, a system of 23 volunteer-operated earthquake monitoring stations across the state, records earthquakes in Ohio. Since their installation by the ODNR Division of Geological Survey in 1999, the monitors have recorded eight earthquakes within our borders.
Hansen said it is important that people not feel shy or embarrassed about reporting an earthquake, even if they think its their imagination. It isnt uncommon that our first indication of an earthquake comes from a person saying they felt something. He said reports can be filed via the Ohio Seismic Network web page at www.ohiodnr.com/OhioSeis
Experts say no place in the world is totally free of seismic activity. Nationwide, Florida and North Dakota have the fewest number of quakes. And, of the worlds seven continents, Antarctica is virtually earthquake free.
My suggestion, however, is not to worry. While no one can guarantee a major earthquake will not occur in the Buckeye State, the chances at least in our lifetime are slim.
Explore the Ohio Seismic Network web page for more information about earthquakes in our state. And, coming soon to that page, youll be able to order and view a new map featuring Ohios 170 earthquake epicenters.
For Further Information Contact:
(614) 265-6811 or