Oklahoma Study Will Examine Injection Wells, Quakes

The Oklahoma Geological Survey is studying the relationship between seismic activity and wastewater injection wells with a survey in the Arbuckle formation.

Sensors will be placed into several injection wells in the Arbuckle group to take various measurements. The Enid News & Eagle reports that each sensor will gather information for at least six months.

SandRidge Energy Inc. agreed to remove several injection wells from operation, allowing four of them to be used in the study. Other companies are also participating in the study.

The number of magnitude 3.0 or greater earthquakes has skyrocketed in Oklahoma, from a few dozen in 2012 to more than 900 last year. Scientists have linked the increase to the underground disposal of wastewater from oil and gas production and state regulators have asked producers to reduce wastewater disposal volumes.

OGS hydrogeologist Kyle Murray said it’s important to understand what going on at the disposal sites.

“It’s a puzzle and this is another important piece. Without this kind of data, we don’t know what’s happening 9,000 feet down. This is the closest we get to validating what makes geomechanical sense,” Murray said.

Oklahoma Corporation Commission spokesman Matt Skinner said the group is excited about the study, and useful data could be used to better tailor responses to seismic activity. According to Skinner, the commission is concerned about activity in Perry, Luther and Fairview.

The operators of 27 oil and natural gas wastewater disposal wells in northwest Oklahoma were ordered to reduce injection well volumes earlier this year after a swarm of moderate earthquakes. The commission said at the time that the total reduction in volume would be about 2.4 million gallons – a drop of about 18 percent.

The disposal wells are operated by eight different companies.