The team of seismologists from Southern Methodist University, which has studied other quakes in the area since 2008, deployed 15 of the earthquake monitors Wednesday. SMU studies of quakes in the DFW Airport and Cleburne areas have concluded wastewater injection wells created by the natural gas industry after fracking are a plausible reason for the temblors in those areas.
But Craig Pearson, seismologist for the state Railroad Commission, said that is not the case with the Irving quakes.
“There are no oil and gas disposal wells in Dallas County,” said Railroad Commission of Texas seismologist Dr. Craig Pearson in a Wednesday email.
Irving City Manager Chris Hillman said two natural gas wells were drilled in Irving in 2009 and fracked in 2010. One remained inactive and the second stopped producing in October 2012. But the city doesn’t allow wastewater disposal wells, so the wastewater was trucked out instead of being injected into the ground.
A report from the SMU team on 20 monitors near Azle and Reno, where another series of earthquakes took place, has not been completed.
This week the team has been working with Irving city leaders to find answers.
“We know the seismic activity has concerned residents and we understand they have lots of questions, as do we,” Hillman said in a statement.
The city has posted information about the earthquakes on the city website.
SMU seismology professor Brian Stump will be among experts scheduled to brief the Irving City Council on Jan. 15.
Residents who are worried the little shakers mean a big one is coming can probably rest easy, said a geophysicist with the U.S. Geological Survey.
“There are no large active faults in Texas, just smaller-type faults,” said geophysicist John Bellini on Wednesday in a telephone interview. “Because of that, it’s not likely that Texas would have a large earthquake.”
Although cracks in walls were reported in some cases, but home foundations are probably safe, said Bruce Talmadge at Discount Foundation Repair Specialists in Irving
“If a homeowner had previous foundation repair work, there’s a good chance the earthquakes may have created problems,” he said. “But if a homeowner had a good foundation, I don’t see where these earthquakes have caused problems yet.”
No injuries or damage reported
The minor quakes in Irving, 12 on Tuesday and Wednesday, were felt all across the area, mostly on the Dallas side of the Metroplex, but no injuries were reported.
After the second quake Wednesday, Twitter users said they felt the shaking in Highland Park, Lakewood, Coppell and along Skillman Street in Dallas. On social media Tuesday, people in Dallas, Addison, Richardson, Garland, Carrollton, Irving, Lewisville, Rowlett and more reported feeling quakes,
By the end of the school day Wednesday the Irving school district had conducted “drop, cover, hold on” earthquake drills at all 38 campuses, just in case of a large quake.
“The safety of our students and staff is always our top priority,” a Wednesday statement from Irving school officials says. “In the future, we will conduct earthquake drills in the same way that we have fire drills, tornado drills, etc.”
Irving police were flooded with calls to the point where they asked residents to stop calling to report quakes unless emergency medical services were needed.
Detective James McLellan estimated Wednesday that dispatchers received about 100 earthquake-related 911 calls on Tuesday afternoon and another 150 Tuesday night and early Wednesday.
“The 911 system was overwhelmed,” he said. “And operators were quickly trying to reach callers with a true emergency.”
McLellan said he felt Tuesday’s 3.5 magnitude quake. “I had my first earthquake,” he said. “I was sitting at my desk and at first I thought it was someone dropping something upstairs or someone slamming a door. When it continued to shake, I realized it was an earthquake.”
A spokesman for Dallas/Fort Worth Airport said crews have felt the quakes, but had no reports of damages or any kind of outages.
“DFW has responded to each report of an earthquake by conducting active inspections of runways and taxiways on the airfield and by conducting systems checks of all of the airport’s critical systems and infrastructure,” said airport spokesman David Magana in a Wednesday email. “The FAA has reported no issues with air traffic control operations in their towers, and all airlines have reported normal systems operations.”
Several of the quakes were near tracks operated by DART, and a spokesman said crews are inspecting tracks daily as usual.
“That has always been the case,” said spokesman Mark A. Ball on Wednesday in an email. “We're certainly looking for anything out of the ordinary that might have been caused by the recent seismic activities.”
Nearly all the quakes have been near the site of the old Texas Stadium, an area that has had 27 minor earthquakes since September, according to the USGS (see map of recent ones here).
A 3.6-magnitude quake Tuesday at 3:10 p.m. was the strongest in the recent outbreak.
Residents at the Stone Tree Mobile Park in Irving wondered felt the tremors. The mobile home park is on Maryland Drive, walking distance from the old Texas Stadium.
"I got scared because it was strong," said Aracely Vasquez in an interview in Spanish. "Why is it happening? It never happened before."
Belinda Fair and her daughter, Erica, who also live at the mobile park, said they felt several quakes Tuesday. "You see it all over Facebook. Everybody is talking about it." Belinda Fair said.
David Griggs, a lawyer with offices in Carrollton, said he felt three earthquakes Tuesday. The first, shortly after 3 p.m., was “just a jolt," Griggs said. "The rafters shook."
At first, he and his co-workers wondered whether a worker had dropped something on the roof, but they soon learned from news reports that they had experienced a tremor. He felt two more at home in Farmers Branch Tuesday night.
North Texas has had more than 30 minor earthquakes since 2013, and some of the strongest were in November and December 2013. Three 3.6-magnitude quakes were: Dec. 8 north of Azle, Nov. 28 north of Mineral Wells and Nov. 19 northwest of Azle.
©2015 the Fort Worth Star-Telegram. Distributed by Tribune Content Agency, LLC.
