The reaction was swift to the strong earthquake activity in Northwest Oklahoma.
The Oklahoma Corporation Commission, the state’s regulatory authority, announced a disposal well reduction April 9.
The OCC assertively directed a wastewater disposal well in the Covington/Douglas area to reduce disposed volume into the Arbuckle formation, from 17,000 barrels a day to 5,000 barrels a day.
“This is an ongoing situation, and further actions are possible,” an OCC media advisory released Monday afternoon stated.
Five earthquakes were recorded in Northwest Oklahoma since the previous Sunday evening.
The largest, a magnitude 4.5, occurred at 5:22 a.m. Monday. It first was reported as magnitude 4.3 but later was upgraded, by U.S. Geological Survey.
It was centered 5 miles north-northeast of Marshall and 6 miles south of Covington, according to USGS. It was 2 miles deep.
The five followed another swarm of quakes that started toward the end of last week in the same general area of southeast Garfield County.
The largest in the early swarm measured magnitude 4.6 on Saturday.
While the threat of induced earthquakes from well activity is important, it’s much smaller than the threat linked to injection of oil and gas wastewater in the north-central area of the state
“Production within the 15 thousand-square-mile earthquake Area of Interest (AOI) resulted in an unprecedented amount of salt water, which was already in the formation, coming up with the oil and natural gas,” OCC’s Oil and Gas Conservation Division Director Tim Baker said last month.
“That produced water was put back underground using disposal wells. There is broad agreement among researchers that disposal of these large amounts of water into the Arbuckle, the state’s deepest formation, can be linked to the high earthquake rate we saw in recent years within parts of the AOI.”
OCC Chairman Dana Murphy has said she thinks the decrease in earthquakes can be attributed to a combination of oil prices, and measures the OCC has taken.
Oklahoma residents with shaking foundations appreciate an expedited response time.
“By the time that we see that there’s an earthquake, if we need to take a directive activity, we can usually do it in less than two days. It used to take us weeks because we would get the data — some of it was faxed in, some of it was handed to us. We didn’t have it coming in in an appropriate format,” Murphy said in November 2017.
That’s the result of historic collaborations between industry, regulators and researchers.
We appreciate these speedy responses to earthquakes in our area.