Texas Earthquakes: The Verdict is Still Out

June 8, 2015 Elizabeth Alford

The Texas Railroad Commission is publicly questioning scientific evidence that links fracking to earthquakes.

Last Friday scientists met with Railroad Commissioner Ryan Sitton and other officials for a technical discussion about the science behind a recent study that links fracking and earthquakes.

The peer reviewed study led by researchers at SMU concluded that earthquakes in the north Texas communities of Azle and Reno were likely triggered by the wastewater disposal methods used by fracking companies. This common process is to inject the saltwater waste through high pressure methods deep into storage facilities underground.

During the meeting, SMU geophysics professor Heather DeShon reaffirmed the findings stating that "You only need a pressure change of 1.5 PSI to trigger an earthquake on a critically-stressed fault line,"

During the meeting, the scientists also asked Commissioner Ryan Sitton for a list of things that would be helpful for further studies including:

Requiring disposal well operators to provide bottom hole measurements would be very helpful in their research.
Getting saltwater disposal volume and pressure data on either a monthly or quarterly basis instead of yearly

“I have not reached the conclusion that oil and gas activity is the causal factor,” said Craig Pearson, the Railroad Commission’s staff seismologist. “While we remain concerned about seismic activity in the state, we still haven’t had a hearing where we’ve had a definite case made that a specific operator is associated with any specific earthquake activity.”

Texas Quakes Alarm Residents

January 9, 2015 Elizabeth Alford

Residents in the north Texas community of Irving were rattled on Tuesday by a series of earthquakes that have many anxious for answers. Within a 36 hour period, the U.S Geological Society registered close to a dozen quakes in the region ranging in intensity from a 2.6-3.7 on the richter scale. Though there were no reports of injury, the tremors drew huge concern in an area where quakes are, historically, rare.

Though the amount of earthquakes in Texas hardly compares to our west coast neighbors, they have been on the rise in recent years, causing many to make a connection between increased seismic activity and the fracking throughout the state.

Several studies including from SMU and UT in Texas and a USGS study in Ohio have linked earthquakes to wastewater injection wells. But this seems unlikely here since there are no such wells in the county and experts warn against jumping to conclusions.

“It’s premature to speculate on the cause of this current series of seismic events,” said Brian Stump, Albritton Chair of Geological Sciences at SMU, in a statement reported in the Dallas Morning News yesterday. “We’re just getting started. We want to support the local community in understanding these earthquakes.”

“It could just be a natural event that just happened to occur. We’re going to be exploring all possibilities, including any contributions that the oil and gas industry might have in terms of injection of fluids or extraction of fluids in the subsurface.”

— Robert Williams, a Geophysicist with the USGS

Whatever the cause, North Texas residents were clearly shaken and taxed emergency response systems with an overwhelming amount of 911 calls. Additionally local school districts went into quick action and initiated mandatory emergency earthquake drills for school children.

Eagle Ford Quakes Linked to Disposal and Injection Wells

February 11, 2014 Kirk Eggleston

Since the drilling boom began in the Eagle Ford Shale, scientists have recorded a steady up-tick in earthquakes in South Texas. In a KENS-TV report, Seismologist, Cliff Frohlich, explains that there could be a link between South Texas quakes and disposal and injection wells.

Also read: Is Eagle Ford Production Causing Earthquakes?

Video Highlights

South Texas residents concerned about earthquakes and connection to oil production
Difficult to determine distinction between man-made and naturally occurring earthquakes
Increase in earthquake activity since drilling boom began in Eagle Ford
Earthquakes could be linked to disposal and injection wells

“Given that there’s tens of thousands of oil and gas wells in Texas and tens of thousands of injection wells, if [hydraulic fracking or disposing of fracking fluids] was hugely dangerous, then Texas would be famous because it was rocking with bad earthquakes all the time, but it’s not.”

— Cliff Frohlich, Seismologist with The University of Texas

Is Eagle Ford Oil Production Causing Earthquakes?

August 28, 2013 R.T. Dukes

The surge in Eagle Ford production over the past few years has likely led to small earthquakes in the region.

Enough oil and water is now being produced that it is likely rocks are settling and faults are slipping, which causes small earthquakes.

That's the conclusion from a two-year study completed by the UT Institute for Geophysics.

The study was published in the Earth and Planetary Science Letters.

Findings from the study include:

No link found between hydraulic fracturing and earthquakes
Authors compare South Texas to California during the oil boom of the 20th century
Earthquakes are likely linked to areas of oil & gas production and are often undetectable at the surface

In other studies, seismic activity was linked to waste water injection wells. Both a UT study in the Barnett and a USGS study in Ohio have linked earthquakes to injection wells. The results of this study seem to indicate we're going to find differences across regions.

“Science is seldom that simple.”

— Mr. Frohlich

[ic-l]*Note - The study was done while the National Science Foundation had measurement tools in place that have never been available in South Texas. 58 of the tremors measured were not recorded by tools the USGS has in place. I trust the researchers at UT, but it is tough to call a two year peek into eons of data a significant sample size. This probably won't be the last study on the topic, so we'll have to watch for additional data points as they become available.