Boom in West Texas oil drilling leads to major earthquakes

In recent weeks, the West Texas oil patch has been rocked by two 5.4-magnitude earthquakes that were among the largest in the state’s recorded history. People reported feeling the earthquakes hours away in major cities.

In November, one of the earthquakes struck near the small town of Orla, where huge rigs barrel up and down the highway every day, transporting everything from oil and gas to water and sand. The region is one of the most active parts of the Permian Basin oil field and is where much Permian drilling activity has been concentrated in recent years.

This remote corner of the state has also recently been a hotbed of earthquakes.

At the Armadillo Hotel in Orla, a dusty land of rows of trailers where roughnecks sleep between shifts, Angeles Ajuntas said he felt last month’s big earthquake. She has worked here for a year, she said, and the quake centered just a few miles away was the first she noticed.

“I was more shocked,” she said. “I said, ‘I didn’t think we could get them here,’ and then I had my colleagues say, ‘Oh yeah, you’ll get used to it.'”

This region has seen a flurry of smaller earthquakes in recent years that don’t always visibly shake the ground.

“2017, 2018 is when things really started to ramp up exponentially,” said Robert Skoumal, a seismicity expert with the US Geological Survey who has studied earthquakes.

Skoumal’s research has shown that the vast majority of these earthquakes are caused by oil companies pumping wastewater from the drilling process into the ground. Skoumal explained how exactly it happens:

“The activities are not earth-shaking,” he said. “It’s more the changing stresses that act on these faults, and those stresses, in turn, cause these faults to slip, which then causes the wobble.”

This year alone – in the county where last month’s big earthquake struck – companies have pumped more than 49 billion liters of sewage into the ground, according to data compiled by analytics firm Rystad Energy.

“It’s a crazy amount of water,” said Rystad’s Ryan Hassler, who noted that oilfield earthquakes are not new.

Oklahoma saw a flurry of earthquake activity at the dawn of the fracking boom, a trend that was later repeated in North Texas when drilling took off there. But these days in West Texas, Hassler said, there’s a lot more wastewater coming along with drilling.

“You’re talking about a 3:1 to 6:1 water-to-oil recovery in these wells,” he said. “The wells have gotten bigger, so with that we’re seeing more [oil] production, but we’re also seeing a lot more water production.”

The response from regulators at the Texas Railroad Commission, which regulates fossil fuels, not railroads, is also markedly different now.

When scientists noticed the link between earthquakes and oil and gas less than a decade ago, regulators were initially skeptical. They have since embraced the science and even acknowledged that there is a link between industry and earthquakes.

“The Railroad Commission has been very aggressive in reducing activity,” said Todd Staples, head of the Texas Oil and Gas Association trade group.

Regulators’ actions on the matter have led to “severe financial consequences” for companies in the area, Staples added.

And regulators are still investigating the recent near-record earthquakes. In some parts of West Texas, they have taken direct action to close sewage disposal sites. But around Orla, close to the big one in November, they are relying mainly on promises and plans developed by the oil companies themselves.

Staples said the industry knows more shutdowns could happen if the earthquakes don’t slow, but critics argue officials could be more aggressive now.

“I think it shows that the commission is really dependent on the industry to police itself,” said Virginia Palacios with the Shift Commission, a sort of watchdog group focused on the Railroad Commission.

Regulators have set targets for reducing earthquakes within the next two years. Meanwhile, Angeles Ajuntas at Hotel Orla said she is not too worried about the earthquakes.

“But it’s also worrying because you don’t know what else could happen,” she said.

For now, earthquakes are just a fact of life in the oil patch.