There is evidence that fracking is linked to earthquakes.
It makes sense. An earthquake happens when plates in the earth’s crust build up enough pressure to overcome the friction holding them in place. When we pump fracking fluid into the earth, it acts as a lubricant which reduces the force of friction, allowing those plates to move with less pressure / energy.
There is significant risk of catastrophic earthquakes in California, and other parts of the world. Perhaps we can reduce the risk of “the big one” by using fluid injection to trigger smaller preventive earthquakes?
This would be analogous to how forest rangers set preemptive fires to clear away brush to avoid a massive forest fire.