News Release

COLUMBUS, OH -- State geologists are getting a better understanding of earthquake activity in Ohio, thanks to a new 14-station network of seismographs installed recently by the Ohio Department of Natural Resources (ODNR). The new seismic network is the most comprehensive earthquake-monitoring system ever established in Ohio, and is considered by geologists to be among the best in the midwest.

The 14 seismic monitoring stations are located at universities and government facilities in or near Ashtabula, Athens, Bowling Green, Celina, Cincinnati, Cleveland, Columbus, Lancaster, Lima, Painesville, Portsmouth, Toledo and Wooster.

"Ohio has experienced 120 earthquakes over the past two centuries -- enough to qualify western Ohio as the second most active earthquake zone in the eastern half of the United States," said Tom Berg, Ohio's chief geologist. "This new system will help us monitor even the smallest tremors in Ohio so we can analyze and identify the exact locations of faults that might one day produce larger earthquakes."

Prior to installation of Ohio's new seismic network earlier this year, there were only two active seismographs in the state -- at Toledo and Wooster. Ohio geologists were often dependent on seismographs in Kentucky and Michigan to record tremors here. According to Mike Hansen, senior geologist with ODNR and coordinator of the seismic network, sophisticated technology used in Ohio's new system replaces the traditional seismograph machine, which used a pen to scribble lines across a paper drum. By using a desktop computer, Internet connection and Global Position System receiver, each unit in the new seismic network is electronically interlinked to provide quick and accurate information. The exact epicenter, magnitude and timeframe of any seismic activity can now be determined in a matter of minutes by checking data from any three or more of the seismograph units.

The 14 monitoring units in the new network are located in the most seismically active areas of the state or near regions that provide ideal conditions for detecting and locating very small tremors -- which are often undetected by humans.

The largest earthquake known to have originated within Ohio's borders occurred on March 9, 1937, in Shelby County -- measuring approximately 5.5 in magnitude on the Richter scale. In fact, Shelby and Auglaize counties, in western Ohio, form the most active seismic area in the state and have been the epicenter for more than 40 earthquakes since 1875. Ohio's other seismically active areas include northeastern and southwestern Ohio, recording 20 and 10 earthquakes respectively since the 1800s.

Ohio's new seismic network, referred to as OhioSeis, was developed by Dr. Larry J. Ruff at the University of Michigan. Purchase of seismometer equipment and other instruments that detect Earth motions has been funded by the Federal Emergency Management Agency (FEMA) as part of its National Earthquake Hazards Reduction Program. The computer and Internet connection at each reporting station are provided by the cooperating university or institution.

The ODNR Division of Geological Survey will manage the network from its Ohio Earthquake Information Center, currently under construction at Alum Creek State Park, north of Columbus. The new facility will function primarily as a geologic repository, however it will have a specially constructed room for earthquake monitoring.

"Ohio's new seismic network provides a whole new dimension of understanding about the pulse of the Earth beneath our state," Berg said. "Although the new seismograph network cannot predict earthquakes or alert us prior to an event, it does provide fresh insight into the risk of earthquakes in Ohio, helping us make wise land-use decisions."