Power outages may have contributed to recent earthquakes in the Fairview area, according to Oklahoma Corporation Commission officials.
"The seismic events that occurred during the week of January 4th, 2016, in the Fairview area appear to have a very close correlation to the (winter) storms that created power outages in such area. It is believed that the power outage may have created a situation where a number of producing wells were shut in, then simultaneously came back on line," OCC Oil and Gas Division Director Tim Baker wrote in a letter to well operators. "When the wells began producing again, this apparently resulted in a tremendous volume of produced water being disposed into the Arbuckle formation at the same time. The OGCD recommends that in the future, when a power outage of this magnitude occurs, the production volumes be staged or phased in over a period of time."
OCC spokesman Matt Skinner said the commission does not determine the cause of earthquakes, and the ultimate cause of the recent temblors in the Fairview area will have to be determined by researchers. The OCC observed the earthquakes after power outages, and they have been told by researchers it is "not a good idea" for wells to come back on all at once.
"We are not qualified to make correlation determinations. That is a very complex area of science," Skinner said.
In response to the quakes, the OCC is directing 27 wastewater disposal wells injecting into the Arbuckle formation to reduce volume, according to a media advisory. The reduction will amount to 54,859 barrels a day — a cut of about 18 percent. All actions must be taken by Feb. 9.
Work continues on a larger plan, Baker said.
“The data available indicates that a much larger approach to the earthquakes in that entire part of northwestern Oklahoma is needed, and we have been working on such a plan. However, given the recent earthquake activity in the Fairview area, the plan announced today is a necessary step as part of this ongoing process,” he said.
Skinner said the larger plan will involve the entire region of seismicity in northwest Oklahoma.
"We're looking at a regional approach, rather than an area approach," he said.
Since Jan. 6, there have been 38 magnitude 2.5 or greater temblors in the Fairview area, U.S. Geological Survey records indicate. Those quakes included 21 measuring magnitude 3.0 or greater, and five measuring magnitude 4.0 or greater.
There have been 101 magnitude 2.5 or greater earthquakes recorded in the state since the beginning of the year — including 39 measuring magnitude 3.0 or greater, and six measuring magnitude 4.0 or greater.