Oklahoma Quakes

Jan 17, 2013

Earthquakes are on the rise in Oklahoma, and researchers, regulators and the public are starting to ask questions about the state’s seismic risks. In the first of a series of reports on Oklahoma earthquakes, State Impact’s Joe Wertz explores the history of Oklahoma’s underground and the largest quake since statehood.

Mary Reneau says you haven’t lived until you’ve cleaned coffee grounds mixed with molasses and shards of glass off the floor.

(MARY RENEAU) “God, it was such a mess.”

The 5.6-magnitude earthquake in November 2011 left the rest of Reneau’s house uninhabitable. The chimney collapsed onto the roof of the two-story home and crashed through the ceiling above the living room couch. Windows and mirrors shattered, spraying bits of glass everywhere. Every doorway had a crack. The water main was severed. Mary and her husband Joe escaped uninjured. But That first night...

(MARY RENEAU) “... FEMA wouldn’t let us stay here because they didn’t know how much of the upstairs was compromised.”

The Reneaus didn’t return to their home for five months. They lived in a trailer on their 490-acre ranch and waited while crews stripped the house down to its frame and rebuilt it.

(JOE RENEAU) “The damage to this house was over $200,000.”

The Reneaus live near Sparks, a town of about 170 people situated 60 miles northeast of Oklahoma City. This part of the country is known for tornadoes not earthquakes, but that perception is changing along with an increase in seismic activity. The Oklahoma Geological Survey’s Austin Holland:

(AUSTIN HOLLAND) “This uptick started to occur in 2009, and really kicked into full-gear in 2010, and has continued today.”

More than 1,000 earthquakes were recorded in Oklahoma in 2010. The next year, there were more than 1,400 earthquakes, making 2011 the most seismically active year on record. That’s a big jump from the 35 earthquakes per year the state averaged in the decade prior. New research suggests a possible link between disposal wells used by oil and gas companies and increased earthquake activity. The potential connection is being studied in Oklahoma and other states, like Texas, Arkansas, Colorado and Ohio. The November 5, 2011 earthquake was the strongest in at least a century. A 4.7-magnitude earthquake was recorded a day earlier, and a strong aftershock was recorded the day after. And if you draw a line ...

(JOE RENAU) “... between the three, our house sits right on the epicenter of the three quakes. Right in the center of the triangle.”

State emergency authorities say the 5.6-magnitude earthquake and its aftershocks damaged about 200 buildings throughout the state. Holland says the increase in earthquakes is interesting and important, but not necessarily alarming. Most of these earthquakes are small — and most can’t be felt. But Holland says the threat of property damage is real. And Oklahoma is seismically active. It has earthquakes but ...

(AUSTIN HOLLAND) “ ... People tend to forget about them because they’re much less frequent than in places like California and these other places that are on plate boundaries where earthquakes are much, much more frequent.”

Earthquake academics spend a lot of time in those states. Very few researchers in Oklahoma study seismicity full-time. StateImpact surveyed the major colleges and universities and could find only two. But there is an economic incentive in knowing what’s going on underground in Oklahoma: Oil and natural gas. Oklahoma’s geology, and a lot of related data about buried fault lines and other seismic phenomenon has been recorded and analyzed by geoscientists working for energy companies.

(AUSTIN HOLLAND) “Their computer resources alone put mine to shame. The amount of manpower they can put towards a project or problem is incredible compared to what resources we have here to do.”

There’s a lot of money at stake, and this type of seismic and geologic data — knowing where to drill and how — is a big part of what makes an oil and gas company successful. Being secretive can help an oil and gas company stay competitive. And research suggesting that oil and gas activity could be contributing to earthquakes may make energy companies even less likely to share what they do know. For State Impact, I’m Joe Wertz.