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Ohio Utica Shale

Earthquake rate in Oklahoma grows by 50 percent

By Bob Downing Published: May 6, 2014

From the U.S. Geological Survey today:

The rate of earthquakes in Oklahoma has increased by about 50 percent since October 2013, significantly increasing the chance for a damaging quake in central Oklahoma.

In a new joint statement by the U.S. Geological Survey and Oklahoma Geological Survey, the agencies reported that 183 earthquakes of magnitude 3.0 or greater occurred in Oklahoma from October 2013 through April 14, 2014. This compares with a long-term average from 1978 to 2008 of only two magnitude 3.0 or larger earthquakes per year. As a result of the increased number of small and moderate shocks, the likelihood of future, damaging earthquakes has increased for central and north-central Oklahoma.

“We hope that this new advisory of increased hazard will become a crucial consideration in earthquake preparedness for residents, schools and businesses in the central Oklahoma area,” said Dr. Bill Leith, USGS Senior Science Advisor for Earthquakes and Geologic Hazards. “Building owners and government officials should have a special concern for older, unreinforced brick structures, which are vulnerable to serious damage during sufficient shaking.”

The joint statement indicates that a likely contributing factor to the increase in earthquakes is wastewater disposal by injection into deep geologic formations. The water injection can increase underground pressures, lubricate faults and cause earthquakes – a process known as injection-induced seismicity. Much of this wastewater is a byproduct of oil and gas production and is routinely disposed of by injection into wells specifically designed and approved for this purpose. The recent earthquake rate changes are not due to typical, random fluctuations in natural seismicity rates.

Oklahoma’s heightened earthquake activity since 2009 includes 20 magnitude 4.0 to 4.8 quakes, plus one of the two largest recorded earthquakes in Oklahoma’s history – a magnitude 5.6 earthquake that occurred near Prague on Nov. 5, 2011, which damaged a number of homes and the historic Benedictine Hall at St. Gregory's University in Shawnee.

As a result of the increased seismicity, the Oklahoma Geological Survey has increased the number of monitoring stations and now operates a seismograph network of 15 permanent stations and 17 temporary stations. Both agencies are actively involved in research to determine the cause of the increased earthquake rate and to quantify the increased hazard in central Oklahoma.

Information about earthquake preparedness can be found at the following websites: and




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Ohio Department of Natural Resources' Division of Oil and Gas Resources Management State agency Web site.

ODNR Division of Oil and Gas Resources Management. State drilling permits. List is updated weekly.

ODNR Division of Geological Survey.

Ohio Environmental Protection Agency.

Ohio State University Extension.

Ohio Farm Bureau.

Ohio Oil and Gas Association, a Granville-based group that represents 1,500 Ohio energy-related companies.

Ohio Oil & Gas Energy Education Program.

Energy In Depth, a trade group.

Marcellus and Utica Shale Resource Center by Ohio law firm Bricker & Eckler.

Utica Shale, a compilation of Utica shale activities.

Landman Report Card, a site that looks at companies involved in gas and oil leases.FracFocus, a compilation of chemicals used in fracking individual wells as reported voluntarily by some drillers.

Chesapeake Energy Corp,the Oklahoma-based firm is the No. 1 driller in Ohio.

Rig Count Interactive Map by Baker Hughes, an energy services company.

Shale Sheet Fracking, a Youngstown Vindicator blog.

National Geographic's The Great Shale Rush.

The Ohio Environmental Council, a statewide eco-group based in Columbus.

Buckeye Forest Council.

Earthjustice, a national eco-group.

Stop Fracking Ohio.

People's Oil and Gas Collaborative-Ohio, a grass-roots group in Northeast Ohio.

Concerned Citizens of Medina County, a grass-roots group.

No Frack Ohio, a Columbus-based grass-roots group.

Fracking: Gas Drilling's Environmental Threat by ProPublica, an online journalism site.

Penn State Marcellus Center.

Pipeline, blog from Pittsburgh Post-Gazette on Marcellus shale drilling.

Allegheny Front, environmental public radio for Western Pennsylvania.