Is fracking responsible for Oklahoma earthquakes?

(CNN) – Oklahoma has been experiencing an explosion in earthquake activity, believe it or not, it's had more than California this year.

But why?

A new study in Science Magazine links the uptick to a controversial drilling practice used by oil and gas companies, an industry that forms one of the pillars of Oklahoma's economy.

CNN's Martin Savidge reports after all this shaking, somebody might want to inspect that pillar for cracks.