EarthquakesOklahoma scientists warn about fracking-induced earthquakes
Using stronger language than in the past, the Oklahoma Geological Survey (OGS) announced on Tuesday that the state’s ongoing waves of earthquakes are “very unlikely to represent a naturally occurring process.” The OGS says that fracking was likely a cause for the increased seismicity. The state’s seismicity rate in 2013 was seventy times greater than the rate before 2008, and rapidly grew to about 600 times greater today, according to the OGS. The average oil well in Oklahoma requires about ten barrels of saltwater to be injected for every barrel of oil that can be pumped out.
Using stronger language than in the past, the Oklahoma Geological Survey (OGS) announced on Tuesday that the state’s ongoing waves of earthquakes are “very unlikely to represent a naturally occurring process.”
As theOklahoman reports, the OGS suspected that fracking, or the wastewater disposal wells that inject large amounts of water into the ground during oil production, was likely a cause for the increased seismicity.
“The observed seismicity of greatest concentration, namely in central and north-central Oklahoma, can be observed to follow the oil and gas plays characterized by large amounts of produced water,” their report stated. “Seismicity rates are observed to increase after a time-delay as injection volumes increase within these plays. In north central and north-central Oklahoma, this time-delay can be weeks to a year or more.”
The report added that the recent quakes experienced by the state “have not occurred in the typical foreshock-mainshock-aftershock sequences that are characteristic of naturally occurring earthquake sequences throughout the world in a variety of tectonic settings.”
The seismicity rate in 2013 was seventy times greater than the rate before 2008, and rapidly grew to about 600 times greater today, according to the OGS.
The more extensive warning follows after many scientists, and even some within the industry, have expressed their belief that the practices are related to the unusually high number of new quakes.
“I don’t see that this is terribly shocking,” said Kim Hatfield, the chairman of the regulatory committee at the Oklahoma Independent Petroleum Association (OIPA). “This is something the Oklahoma Geological Survey, Oklahoma Corporation Commission and OIPA have been working on for well over a year. We knew this was a possibility.”
Hartfield also stressed that state’s oil and natural gas producers had been working closely with regulators on the issue.
“Oklahoma’s oil and natural gas producers have a proven history of developing the state’s oil and natural gas resources in a safe and effective manner. That longstanding commitment to Oklahoma will continue as we work to develop greater understanding of Oklahoma’s seismic events,” he said
Chad Warmington, the president of the Oklahoma Oil and Gas Association, added that even if there was a link, the extent of the impact is still not known.
“There may be a link between earthquakes and disposal wells, but we — industry, regulators, researchers, lawmakers or state residents — still don’t know enough about how wastewater injection impacts Oklahoma’s underground faults,” he said.
Much of the cooperation between corporate and scientific organizations comes down to a better understanding of the science, according to Michael Teague, the secretary of Energy and Environment for the state.
“It’s an evolution on the science side of this and not just from the Geological Survey but the USGS as well,” he said. “You see the evolution on the science, and you’re seeing the evolution on a regulatory level with what the Corporation Commission is doing. We’re trying to make sure the public information keeps up with those changes. It really is unprecedented across the country.”
The average oil well in Oklahoma requires about ten barrels of saltwater to be injected for every barrel of oil that can be pumped out.
