DALLAS – According to Cliff Frohlich, associate director and senior research scientist at the University of Texas at Austin''s Institute for Geophysics, three small earthquakes that occurred over the weekend in the Dallas area appear to be linked to the disposal of wastewater from hydraulic fracturing operations, Huffington Post reported.
A 3.4 magnitude earthquake hit at about 11:05 p.m. on Saturday. It was followed a few minutes later by a 3.1-magnitude aftershock. A third 2.1-magnitude quake occurred at 10:41 p.m. on Sunday.
Before a series of small quakes on Halloween 2008, the Dallas area had never recorded a magnitude-3 earthquake, said Frohlich.
Frohlich said he doesn''t think it''s a coincidence that an intensification in seismic activity in the Dallas area came the year after a pocket of ground just south of Dallas-Fort Worth Airport began to be inundated with wastewater from hydraulic fracturing.
In a study recently published in the journal Proceedings of the National Academy of Sciences, Frohlich found that most earthquakes in the Barnett Shale region of North Texas occur within a few miles of one or more injection wells used to dispose of wastes associated with petroleum production such as hydraulic fracturing fluids.
"You can''t prove that any one earthquake was caused by an injection well," said Frohlich. "But it''s obvious that wells are enhancing the probability that earthquakes will occur."