Oklahoma regulators forced an oil and gas producer to reduce operations on a well used for disposing salt water following a large earthquake that set off a series of seismic activity in the state, Matt Skinner, spokesman for the Oklahoma Corporation Commission (OCC), said on 9 April.
The temblors occurred near Perry, Oklahoma, in the northwestern part of the state, within an area singled out by regulators for the frequency of earthquakes from oil and gas production activities.
The first quake occurred on 7 April, registering at magnitude 4.6, and was followed by several others, including a magnitude 4.5 earthquake that hit near Perry early morning on 9 April, according to the US Geological Survey.
The OCC forced M M Energy to reduce operations on 7 April on a disposal well in the area from 17,000 to 5,000 B/D, Skinner said.