State lawmakers quiz scientists on earthquake study

On a day that small earthquakes continued to shake North Texas, Southern Methodist University researchers testified before a House committee on Monday about their study linking a swarm of previous temblors near Azle and Reno to oil and gas operations.

While no one linked earthquakes recorded near Irving and Dallas in recent days to drilling, lawmakers at the state Capitol were definitely interested in getting a better understanding of what is making the ground shake with more regularity in the Metroplex.

State Rep. Drew Darby, R- San Angelo, chairman of the House Energy Resources Committee, appeared to be in favor of spending at least $2.5 million for a network of permanent and mobile seismometers to measure and identify seismic events.

Another bill by state Rep. Rafael Anchia, D-Dallas, that would provide for a statewide study to analyze the data from those monitors, was also discussed. It was estimated that the year-long study, which would concentrate on events in the Fort Worth-Dallas area, may cost about $1 million.

“I look forward to science driving this discussion as it moves forward,” said Darby. “Confidence in our regulators is key for this committee to ensure that our energy policy for this state is sound.”

The first quake to hit North Texas on Sunday morning was a 3.2 magnitude earthquake centered about two miles north of Irving. A second 2.5 magnitude temblor hit about six hours later, and another 2.7 magnitude was recorded Monday in Farmers Branch. . More than 50 earthquakes have hit the area since November 2013, mostly centered in the western parts of Dallas.

SMU professors Brian Stump and Matthew Hornbach testified before the committee, along with Jon Olson from the University of Texas at Austin, about the study published late last month in the scientific journal Nature Communications regarding 27 earthquakes that occurred northwest of Fort Worth from November 2013 to January 2014.

After analyzing 3D modeling and reviewing historical data on earthquake activity in the area, the researchers concluded that the tremors were not caused by natural phenomenon, such as drought conditions or a natural shift of the Earth’s plates, but by oil and gas activity.

While researchers agreed with Darby that it would be wrong to call the earthquakes near Azle and Reno “frackquakes” — or directly caused by injecting sand and liquids deep into rock formations to extract natural gas — they made it clear that the drilling process was a factor.

Since SMU released its study, the Texas Railroad Commission, which regulates the oil and gas industry and was long reluctant to make any connection between the seismic activity and drilling, has asked XTO and EnerVest Operating to appear at “show cause” hearings in June to explain why their permits should not be canceled and their injection wells shut in.

Max Baker, 817-390-7714

Twitter: @MaxbakerBB