Oklahoma earthquakes triggered by wastewater injection
Pumping vast amounts of fluids underground may have set off swarm of tremors

A WHOLE LOT OF SHAKING In 2009, a series of earthquakes (red dots), part of the Jones swarm, rattled Oklahoma. Dumping wastewater into disposal wells (white squares) may have boosted pressure at faults (black lines), triggering the quakes.
K.M. Keranen et al/Science 2014