Oklahoma official encourages residents to get insurance for rise in earthquakes linked to drilling

Federal and Oklahoma officials aren't quite ready to blame deep injection of drilling wastewater for a recent increase in earthquakes, but last week's swarm warning by the Oklahoma Geological Survey and its federal counterpart has the state's insurance commissioner encouraging people to buy earthquake insurance, Mike Soraghan of EnergyWire reports. (University of California Berkeley Seismological Laboratory graphic)

"Commissioner John Doak may be the first statewide elected official in Oklahoma to publicly react to the U.S. Geological Survey announcement," Soraghan writes. Republican "Gov. Mary Fallin's office last week referred calls to the state's Department of Energy and Environment, which did not respond to a request for comment. But Doak's statement left out what USGS and the Oklahoma Geological Survey said was likely causing the increase: deep injection of waste from oil and gas drilling."

Earthquakes in Oklahoma have risen dramatically since 2009, up from three per year to 40 per year, with more than 200 earthquakes of magnitude 3.0 or higher in the past five years, including the "largest recorded earthquake in the state, a magnitude-5.7 rupture in November 2011, as part of the whole man-made central Oklahoma swarm," Soraghan writes. "USGS officials say earthquakes are now six times more likely in central Oklahoma than they were four years ago. The state and federal agencies said their analysis 'suggests that a contributing factor to the increase in earthquakes triggers may be from activities such as wastewater disposal.' Oklahoma is dotted with more than 4,500 such wells accepting waste fluid from oil and gas operations, " which increasingly use horizontal hydraulic fracturing, a method that requires large volumes of water. (Read more)