The strongest earthquake to hit Oklahoma in nearly five years shook the state Saturday morning, rousing some residents from a dead sleep. It was felt as far north as Nebraska and as far south as Texas.

Updated 6:30 p.m.

Gov. Mary Fallin declared a state of emergency for Pawnee County after the 5.6 magnitude earthquake struck the state Saturday morning, damaging buildings across north-central Oklahoma.

"This emergency declaration will start the process to helping individuals, families and businesses impacted by the earthquakes and serves as a precursor to requesting any necessary assistance,” Fallin said in a statement.

The 30-day state of emergency allows state agencies to make emergency purchases for disaster relief, and is the first step toward seeking federal aid. Fallin encouraged residents to take photos of any damage and submit them through the "OK Emergency" smartphone app.

Credit Brian Hardzinski / KGOU

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KGOU

Updated 1:41 p.m.

The Oklahoma Corporation Commission is shutting down more than 35 disposal wells in a 725 square mile area around the epicenter of Saturday's earthquake.

Spokesman Matt Skinner says the OCC issued the directive because of links between seismic activity and underground wastewater disposal that's part of the oil and gas production process.

Gov. Mary Fallin said the Commission has no data on Osage County because oil and gas operations there are solely under federal control, but the regulatory agency was working with the Environmental Protection Agency to review the area on tribal land.

Fallin says the Oklahoma Department of Transportation found minor issues in state highways and bridges. Six buildings in the Pawnee Nation are uninhabitable due to damage. In the city of Pawnee, three buildings were damaged, as were three homes in rural Pawnee County.

Original Post

The temblor struck shortly after 7 a.m., and the Oklahoma Geological Survey gave it a preliminary magnitude of 5.5. The U.S. Geological Survey rated it at 5.6, and the federal agency says aftershocks may occur.

Why the difference between OGS and USGS calculations?

The earthquake’s epicenter was about 8.7 miles northwest of Pawnee. Gov. Mary Fallin says staff with the Oklahoma Department of Emergency Management are heading to north-central Oklahoma to assess the damage and respond to residents’ needs.

Saturday morning’s quake was the strongest to hit the state since a 5.7 magnitude tremor struck east of Oklahoma City in November 2011. That earthquake injured residents, damaged 200 buildings, and caused one of the historic turrets at St. Gregory’s University in Shawnee to collapse.

Credit Joe Wertz / StateImpact Oklahoma

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StateImpact Oklahoma

The Oklahoma City Fire Department says so far there have been no reports of ruptured gas lines, but Saturday morning they were responding to falling bricks at a home on NE 21st Street between Lindsay and Phillips Aves., just a few hundred yards southeast of the Oklahoma State Capitol.

The Tulsa Area Emergency Management Agency says there have been no reports of any injuries or significant damage.

Oklahoma Natural Gas says if residents smell a leak or hear a hissing noise, they should notify others and leave the premises immediately. Residents shouldn't use appliances or the telephone, or turn off any lights, since electrical currents could spark an explosion.

Call 1 (800) 458-4251 to report a gas leak.

Since 2009 there's been a strong uptick in the number of earthquakes in Oklahoma, and scientists have linked the seismic activity to the oil and gas industry. StateImpact Oklahoma's Joe Wertz is in Pawnee at the quake's epicenter, and will have more information as it develops.

Exploring the Link Between Earthquakes and Oil and Gas Disposal Wells

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