Though the rate of earthquakes “has declined from its peak,” the 5.8-magnitude earthquake near Pawnee has made 2016 the most seismically active year on record “as measured by seismic energy release,” Oklahoma Geological Survey Director Jeremy Boak tells the Enid News‘ Sally Asher.

Charles Lord, senior hydrologist with the Oklahoma Corporation Commission, explains the modified and expanded emergency orders issued Sept. 12 to oil companies in response to  the 5.8-magnitude earthquake over the Labor Day weekend.
Joe Wertz / StateImpact Oklahoma

Federal and state regulators on Monday expanded and modified emergency orders limiting oil and gas activity at wells near a fault line that produced Oklahoma’s strongest earthquake on record.

Regulators are targeting 67 disposal wells in two counties near the damaging 5.8-magnitude earthquake that rocked the state over the Labor Day weekend.

A team of earthquake scientists deploys 12" sensors in a field near Pawnee after Saturday's 5.6 magnitude earthquake.
StateImpactOK / Instagram

More than a dozen wastewater disposal wells in the Osage Nation have been shut down after Saturday’s earthquake – one of the strongest in Oklahoma history.

A disposal well in northwestern Oklahoma operated by Newfield Exploration Mid-Continent.
Joe Wertz / StateImpact Oklahoma

Oklahoma is still experiencing an unusually large amount of shaking, but the rate of earthquakes recorded in 2016 is down from last year.

The slowdown is likely due to reductions in the amount of waste-fluid the oil industry is pumping into disposal wells, which are thought to be causing most of the shaking.

Joe Wertz / StateImpact Oklahoma

Insurance companies moved to limit their exposure as Oklahoma’s earthquake rate exploded, according to an investigation by Reuters.

Examining thousands of pages of documents from the Oklahoma Insurance Commission, reporter Luc Cohen found the efforts by nearly a dozen insurance companies “often occurred at the expense of homeowners”:

Shaken residents line up inside Edmond's Waterloo Baptist Church to voice concerns and ask representatives from the Corporation Commission and the state Geological Survey questions about recent earthquakes.
Joe Wertz / StateImpact Oklahoma

Federal researchers feared Oklahomans were getting inaccurate information and inadequate warnings from state government scientists and officials tasked with studying and responding to a surge of earthquakes linked to oil and gas activity, a StateImpact investigation has found.


A flowchart from ODOT's new manual on inspecting bridges after earthquakes.
Oklahoma Department of Transportation

The Oklahoma Department of Transportation has changed its post-earthquake bridge-inspection plan after a year-long study showed no structural damage from seismic activity.

Under the new plan, which went into effect April 1, ODOT will only inspect bridges after magnitude 4.7 or greater quakes. Regions where bridge inspections are required will expand as earthquake intensity increases:

Structural engineers have condemned a workshop used by monks at St. Gregory's University in Shawnee, Okla.
Joe Wertz / StateImpact Oklahoma

The U.S. Geological Survey on Monday released new maps and models showing Oklahoma has the highest risk for potential shaking from human-triggered earthquakes.

Oklahoma Corporation Commissioner Dana Murphy talks with residents concerned about seismic activity during a March 25, 2015 town hall meeting in Medford.
Joe Wertz / StateImpact Oklahoma

Less than 24 hours after two magnitude 4.0 earthquakes struck central Oklahoma, Corporation Commissioner Dana Murphy discussed the uptick in seismic activity with lawmakers.

The first magnitude 4.2 temblor came Monday evening shortly before midnight, and a second 4.1 magnitude tremor struck shortly after 5 a.m. Both were near the town of Crescent in Logan County.

Some parts of Oklahoma and Texas now have about the same risk of an earthquake as parts of California, according to the U.S. Geological Survey.

The big difference is, the quakes in Oklahoma and Texas are "induced" — they're caused by oil and gas operations that pump wastewater down into underground wells.

U.S. Geological Survey

The U.S. Geological Survey on Monday released for the first time maps that forecast regions that could experience damage from human-triggered earthquakes. Oklahoma has the highest risk for potential shaking, researchers say.

A SandRidge Energy well in northwestern Oklahoma.
Joe Wertz / StateImpact Oklahoma

The Sierra Club filed a federal lawsuit today against three Oklahoma energy companies over earthquakes linked to oil and gas production.

The lawsuit, filed in the U.S. District Court for the Western District in Oklahoma City, accuses Chesapeake Energy, Devon Energy and New Dominion of operating wastewater injection wells that have contributed to a massive spike in earthquakes in Oklahoma and Kansas.

Lawrence Stasyszen, abbott of St. Gregory's Abbey, stands inside the monastery's condemned workshop in Shawnee, Okla. The monastery and nearby college are still reeling from millions in damage from a 5.7-magnitude quake that struck in 2011.
Joe Wertz / StateImpact Oklahoma

In 2014, Oklahoma had more than three times as many earthquakes as California, and this year, the state is on track for even more. A lot of them are small, but some towns are seeing a quake almost every day, and seismologists warn that large and damaging earthquakes are becoming more likely.

The government in the Sooner State has only recently acknowledged the scope of the oil and gas industry’s role in the problem.

seismic readout
Great Beyond / Flickr

A strong earthquake rocked Oklahoma Saturday morning. The U.S. Geological Survey's initial estimate places the quake at a magnitude 5.1, while the Oklahoma Geological Survey estimates 4.8.

Why State And Federal Agencies Record Different Oklahoma Earthquake Numbers

Gov. Mary Fallin and Secretary of Energy and Environment Michael Teague at the Governor's Energy Conference September 4, 2014 in Oklahoma CIty.
Joe Wertz / StateImpact Oklahoma

Gov. Mary Fallin on Thursday approved the transfer of nearly $1.4 million from the state emergency fund to strengthen Oklahoma’s earthquake response.

The money is going to a pair of agencies tasked with researching the earthquake surge and regulating the oil and gas activities likely causing it.