(Update: This story was updated at 9 p.m. Sunday, Nov. 6, to include a new measurement by the U.S. Geological Survey.)
A large earthquake rattled buildings across Oklahoma about 7:45 this evening, with walls trembling for more than 30 seconds.
The U.S. Geological Survey has registered the quake at a 5.0 magnitude with an epicenter about three kilometers — or less than two miles — west of Cushing. The USGS originally posted a magnitude of 5.3, but dropped that to 5.0 about 8:30 p.m.
Oklahomans and Americans across the middle of the country felt a 5.8 magnitude quake that set the Sooner State’s high (wastewater disposal?) water mark Sept. 3. That quake occurred near Pawnee, a small community in northern Oklahoma. On Nov. 1, a magnitude 4.5 quake hit the same area.
On social media Sunday night, people speculated about the size before the U.S. Geological Survey released its measurements. Some believed this most recent large earthquake was stronger than those, and others asked observers to report their experiences to the USGS:
We felt it too, remember to report it to the @USGS https://t.co/VrI5qhCVLX #okquake #earthquake #okwx
— NWS Norman (@NWSNorman) November 7, 2016
Wastewater disposal wells related to oil and gas drilling have been linked to the state’s rapid rise in earthquakes. In October, the federal Environmental Protection Agency recommended a moratorium on wastewater injection near the state’s most earthquake-prone areas.
Sunday night’s quake was the third in Oklahoma over the weekend, with magnitude 3.1 and 3.6 quakes hitting near Perry on Saturday.
Oklahoma City Thunder player Enes Kanter opted for levity on Twitter:
No worries. My boy Russell dunking at the practice facility. ???
— Enes Kanter (@Enes_Kanter) November 7, 2016
More than a year ago, NonDoc published a commentary from Norman-based environmental activist Casey Holcomb warning about the potential effects of a large earthquake on the Cushing Tank Farm, which is said to be the world’s largest oil reserve.
The tank farms at Cushing are operated by various pipeline companies. By some estimates, these storage facilities have a combined capacity of up to 76 million barrels. Some of the country’s largest pipeline operators own storage facilities in Cushing.Enbridge’s facilities there have a storage capacity of 20 million barrels. Plains All American Pipeline LP owns storage facilities that hold up to 12 million barrels.
In October 2014, Cushing experienced10 earthquakes in one week. Two of those quakes were greater than 4.0 in magnitude. Later that month, the Oklahoma Corporation Commission ordered a temporary shutdown of a nearby injection well that had been drilled into the basement rock. Currently, OCC only requires additional monitoring of injection pressures and volumes if an earthquake reaches a magnitude of 4.0 or greater and is within six miles of a disposal well.
