Friday’s earthquake most powerful of the year for Oklahoma

(GRANT, Okla.) The United States Geological Survey said Friday afternoon's earthquake was a magnitude 4.5, centered 9 miles SSE of Medford at a depth of 3 miles. Hours later, the Oklahoma Corporation Commission’s Induced Seismicity Department announced they are directing 3 oil and gas wastewater disposal wells to stop operations until further notice. Another earthquake shook Grant County Saturday morning at 9:55. According to data from the USGS, Oklahoma has experienced 959 earthquakes this year, 24 of which were magnitude 3 or higher. The Grant County earthquake is Oklahoma’s first to top 4 on the Richter scale for 2019. It’s a figure that has dropped in recent years, after the Oklahoma Geological Survey determined most of the earthquakes in central and north-central Oklahoma were very likely triggered by the injection of produced water in disposal wells. The Office of the Secretary of Energy and Environment said Oklahoma has experienced 304 magnitude 3+ earthquakes in 2017, 623 in 2016, 903 in 2015 and 579 in 2014. In addition to installing more monitoring stations, the OGS continues to compile a database of known fault locations to assist regulators and help oil and gas operators avoid them.