Calling the state "seismically active," Oklahoma regulators are working with state Geological Survey (OGS) and seeking more detailed records from oil and natural gas exploration and production (E&P) operators on activity related to well stimulation and wastewater injection practices.
The Oklahoma Corporation Commission (OCC) is proposing rules for E&Ps developed in collaboration with industry. The OCC approved the proposals earlier this month. The Oklahoma Independent Petroleum Association has said it would not oppose new seismic reporting requirements for its members.
Ultimately, Oklahoma's legislature and governor would have to approve the OCC rules, but the three-member panel has made it clear this is the path it intends to follow since 2011, when quakes racked Oklahoma and several other mid-continent states.
More recently, new research on quakes in Oklahoma concluded that earthquakes induced by the injection of wastewater, such as that from oil and gas drilling, can cause larger quakes (see Shale Daily, March 10). Hydraulic fracturing (fracking) was not targeted as a potential culprit.
Quakes in the central United States were relatively uncommon until recent years. In 2011, "numerous moderate-size earthquakes occurred in Colorado, Texas, Oklahoma, Ohio and Arkansas," U.S. Geological Society has reported. Many of these were near wastewater injection wells, and some of the quakes have been the result of human activities, researchers found.
The OCC has cited scientifically proven facts that pumping water deep underground can "lubricate" fault lines and cause quakes. The regulators have noted that fracking disposal wells exist in 70 of Oklahoma's 77 counties, and they "go much deeper than extraction wells."