Oklahoma averaged 2 earthquakes a year and in the last recent years they had thousands. Im no scientist but the guy quoted in this article is, and it seems pretty obvious Fracking absolutely is responsible for these.
http://mobile.nytimes.com/2016/09/07/us/in-puzzle-of-oklahomas-earthquakes-new-data-may-provide-clues.html?module=WatchingPortal®ion=c-column-middle-span-region&pgType=Homepage&action=click&mediaId=thumb_square&state=standard&contentPlacement=1&version=internal&contentCollection=www.nytimes.com&contentId=http://www.nytimes.com/2016/09/07/us/in-puzzle-of-oklahomas-earthquakes-new-data-may-provide-clues.html&eventName=Watching-article-click&_r=1&referer=https://t.co/AvKWNUHruS
https://earthquakes.ok.gov/faqs/