The faster we pump oil wastewater into the ground, the greater our earthquake risk / by Tom Joseph

Injecting wastewater into the ground may be an effective way of disposing of salty fluids created through oil and gas production, but it also comes with a perilous side effect: earthquakes. Now, researchers have found that the rate at which we dispose of this liquid may greatly impact the chance that one of these quakes will occur. The faster we inject this water into the ground, the higher likelihood of induced Earth rumblings.

http://www.theverge.com/2015/6/18/8806749/high-rate-wastewater-injection-trigger-induced-earthquakes