A Series of Strong Quakes in Oklahoma Triggers Republican Scrutiny of Oil Drilling

Lewis Moore is expecting to get an earful Thursday night.

Moore, who represents a chunk of Oklahoma City's northern suburbs in the state House of Representatives, is holding a town meeting about the spate of earthquakes that have rattled homes there since the last days of December. His constituents are "pissed off," he said — And he can sympathize.

"I'm getting jacked up at my house the same as they are," said Lewis, a second-term Republican. "One neighborhood had 25 homes where the rockwork on the inside of the home came off."

Moore's district includes his hometown of Arcadia and part of Edmond, where a magnitude 4.3 earthquake hit December 29 and a 4.2 hit on January 1. The December 29 quake briefly knocked out power to about 4,400 electrical customers. His own home saw damage to exterior masonry and wallboard inside. Glasses fell out of cabinets or were left leaning inside, primed to tumble out the next time the cabinet gets opened.

"We had pictures coming off the wall or off the fireplace mantle and crash to the floor," Moore said.

In the past few years, Oklahoma has gone from having one or two small but noticeable earthquakes a year to two or three a day — a tentative total of 907 tremors of a magnitude 3.0 or above in 2015, according to the Oklahoma Geological Survey. And 2016 is off and running, with more than four-dozen-reported quakes so far.

"I get more calls from the women," Moore said. "The house, that's their nest, and now you're going to screw with the nest? You're lighting people up. They're pissed off."

They're not only pissed off, they're starting to sue. A group of Edmond-area homeowners went to court this week, seeking damages from a group of oil companies that operated wastewater injection wells nearby.

Scientists have linked the quakes to the practice of pumping salty wastewater from the state's thousands of oil wells deep underground. The water gets injected at high pressures or volumes, where it lubricates faults that crisscross the state far below. The quakes have persisted despite state efforts to restrain the practice in some areas — and that has many worried that a bigger quake is in the wings.

Oklahoma is bumping up against something scientists call the Gutenberg-Richter law, which lays out a relationship between the numbers of bigger and smaller quakes. For every 10 earthquakes in the magnitude-2 range, you can expect a 3; for every 10 in the 3-range, you can expect a 4 — a quake big enough to cause minor damage to buildings.

Since Oklahoma had 29 quakes in the 4-range in 2015, plus at least six more in the first two weeks of 2106, the state appears statistically ripe for a bigger quake. But it's not clear whether the human-induced tremors are following the same pattern as those that occur naturally.

"It's a new phenomenon," said George Choy, a Colorado-based research geophysicist with the US Geological Survey. The Gutenberg-Richter law was discovered by observing natural quakes — "But with induced earthquakes, we're not too sure if we can extend that model," he said.

That's something state researchers are investigating as well, said Jeremy Boak, the director of the Oklahoma Geological Survey.

"In general, the Oklahoma earthquakes have been very strongly biased toward the small earthquakes," Boak said. It's possible that the human-induced quakes are releasing the pent-up energy underground "in clusters of smaller earthquakes rather than in individual, larger earthquakes," he said.

But he added, "That's not a technically vetted idea. It's a concept at this point." His agency is still trying to document that suspicion and present its findings to other seismologists.

Related: Oil-Rich Oklahoma Has Been Hit by Nearly Three Dozen Earthquakes Since Wednesday

How big a "big one" might be is another big question mark. The biggest earthquake linked to wastewater injection so far was a magnitude 5.7 that hit the town of Prague, about 50 miles east of Oklahoma City, in 2011. That quake damaged masonry and knocked down a turret on a brick building at a local college.

"We need to be preparing ourselves for a 5.6 or a 6," Moore said. "If we can be prepared for that as much as possible. When and if that happens, we should be in better shape."

Researchers estimate the state may have been hit by a magnitude 7 as much as 500 years ago, Choy said. A quake that size would be capable of inflicting widespread damage in a populated area. But he said a quake larger than a magnitude 6 would be unlikely today, given the makeup of the faults that lie beneath Oklahoma.

State regulators have tried to get a handle on the problem by demanding that injection wells rein in operations after earthquakes happen. In a few cases, they've asked companies to shut down wells entirely. But they can't force the companies to stop, and some oil companies have refused their demands.

Moore said bills have already been introduced to give the Oklahoma Corporation Commission, the state oil regulator, more power over the practice. Lawmakers return to session in February, and Democratic lawmakers are holding their own public forum on the earthquakes on Friday.

"We need to give the Corporation Commission more authority to stop injections," he said.

But regulatory action has been slow to come in Oklahoma, where an estimated one in five jobs comes from the oil industry. That's frustrated people like Angela Spotts, an anti-fracking activist from Stillwater who expects to be one of the people giving Moore an earful.

"I don't think anything is being done as fast as it should," she said. "There's not enough being done, and it's not being done fast enough. We've known this since 2009, and here we are."

Spotts wants a total halt to wastewater injection, saying some of the worst earthquakes have happened since the state started restricting wells.

"More and more people are really feeling beat down," Spotts said. "We're emotionally drained. Now the news is starting to tell us we have to prepared, we have to be anchoring our bookcases and protecting what's hanging on the wall. The big one is coming." But she asked, "Why should I have to live with the constant risk and fear of a big one?"

Related: Welcome to Quakelahoma

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