West Texas oil country was hit by the state’s fourth-largest earthquake on record, Friday, exactly a month after the same region was hit by the state’s third-largest quake. Oil and gas fracking operations, especially underground wastewater injection, in the south-central U.S. has been connected to earthquakes in the region. The Texas Railroad Commission, which regulates the state’s oil and gas industries, prohibited fracking waste water injection activity at well sites in the Gardendale Seismic Response Area in the Permian Basin, where the earthquake occurred. The Commission, which is already investigating whether the November quake was connected to the widespread fracking activity in the region, said Saturday it will also investigate whether this quake is connected to those activities. (Earthquake: Dallas Morning News, Gizmodo, AP, Lubbock Avalanche-Journal; RRC & fracking: Fort Worth Star-Telegram, AP)