Now, these are very teeensy earthquakes. Some have argued that it is worth sacrificing Blackpool for the sake of cheap gas. :) The usually-required deep water injection is not mentioned here, I know that causes earthquakes. I can't see ordinary fracking causing earthquakes unless the shale is right on top of the granitic basement.
In general, I don't see how you can continue fracking without the deep injection, but perhaps on the coast they just dump this toxic water in the ocean!