ODNR UPDATES OHIO EARTHQUAKE MAP TO REFLECT
STATEWIDE SEISMIC ACTIVITY SINCE 2002
Map also includes newly discovered information about historic earthquakes in the area
download the map
COLUMBUS, OH - More than 30 earthquakes have occurred in and around Ohio since 2002, spurring the Ohio Department of Natural Resources (ODNR) Division of Geological Survey to publish an updated map that pinpoints the location and approximate magnitude of these recent seismic incidents. The revised map also includes new information about historic earthquakes in the region.
More than 200 earthquakes with a magnitude of 2.0 or greater have occurred in the Ohio region since 1776. While it may seem like earthquakes are occurring more frequently in recent years, ODNR’s Ohio Seismic Network attributes this perceived change to improved technology and communication among people who experience the earthquakes.
The new map, which includes all of Ohio’s recorded earthquakes, shows a concentration of earthquake epicenters in two areas of the state: western Ohio in the vicinity of Shelby County, and along the Lake Erie coast in Lake County at Painesville. Users can apply information from the map to determine earthquake insurance rates, construction strength determinations for bridges and buildings, and to research deep-earth structures such as hidden faults.
Michael C. Hansen, coordinator of the Ohio Seismic Network, researched an extensive collection of earthquake catalogs, accounts of earthquakes in old newspapers and information in the files of the Division of Geological Survey to uncover several previously unknown historic earthquakes to add to the new map. From this information, he also found several non-seismic historic events (e.g., explosions, atmospheric phenomena and rockfalls) that were mapped as earthquakes on the 2002 map. These false earthquakes were removed from the new version.
Earthquakes reported before 1970 by the public - often less accurate than seismic station reports available after 1970 - are depicted by a different color symbol on the new map than post-1970 earthquakes.
The 2007 map has an explanatory text and chronological table listing exact coordinates and other details for each Ohio earthquake, such as earthquake event time, depth, size of the area felt and information source. County lines and county seats, latitude and longitude and known faults deep below the surface are also depicted on the map. These features are designed to help map users relate points of interest with earthquake information.
The wall-size Earthquake Epicenters in Ohio and Adjacent Areas (map EG-2) measures 50 inches by 35 inches and is available for $10 (plus tax and mailing) from the ODNR Geologic Records Center at 614-265-6576 or via e-mail geo.survey@dnr.state.oh.us. A free page-size version of the map and chronological listing of earthquake epicenters is available on the Ohio Seismic Network’s website: www.ohiodnr.com/OhioSeis.
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For Further Information Contact:
Michael C. Hansen, Ohio Earthquake Information Center
(740) 548-5979
-or-
Jane Beathard, ODNR Media Relations
(614) 265-6860