Earthquake Map (IMAGE) University of Texas at Austin Caption Seismic events with magnitude (M) ? 2.5 that occurred from January 2009 through December 2017 in the Oklahoma,southern Kansas,Permian basin,and Eagle Ford play study areas. There were 8532 events in the Oklahoma/South Kansas cluster, including four M ? 5.0 events (labeled). Credit Scanlon et al. Usage Restrictions Include credit License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.