Oklahoma has emerged as the world leader in earthquakes. Before 2008 they had an average of one or two of 3.0 magnitude or greater per year...in 2014 they had 585, according to Eric Levitz. Today, 11/13/15, reportable earthquakes totaled 6, for the week 66, the month 195, and the year 2,169. (these figures will change if you follow the link) What changed since 2008? Fracking.
lots of little earthquakes prevent few but larger ones. subsidence can of course result from creating underground voids. but is that the kind of earth movement these are? fracking is a bad idea for a lot of reasons, but it doesn't seem a likely candidate for a direct connection. not an impossible one, but it would take more details then provided to determine its probability.