Published March 30, 2015 at 540 × 393 in Oklahoma Courts to Ponder Negligence and the Link Between Fracking and Earthquakes Oklahoma Earthquake Activity. Blue = 1970-2008, Red = 2009-2014 usgs.gov ‹ Return to post Share Your ThoughtsCancel reply This site uses Akismet to reduce spam. Learn how your comment data is processed.