A magnitude 4.7 earthquake struck northern Oklahoma early on Thursday, rattling residents out of their beds and shaking the ground across a 100-mile (160-km) radius that included the city of Tulsa and the state of Kansas. Reuters. Nov 20 2015
http://www.reuters.com/article/us-quake-oklahoma-idUSKCN0T80XS20151119#sKceVYUQOAQyhKZZ.97