“I’ve long suggested the Mid-American rift is the cause of the swarm in KS and OK.”
The New Madrid Fault System
Earthquake activity in the New Madrid region is concentrated in an area of weak ancient crust called the Reelfoot Rift. About one billion years ago the
continent began to rift apart in this region, but the rifting never completed. What remains is a weak zone in the continent which has been reactivated by present-day stresses in Earth, resulting in seismic activity.
http://www.eas.slu.edu/eqc/eqc_publ/Flyers/PDFs/NMstructure.pdf
It’s obvious the number of people on the edges are causing it to shift and could possibly lead to the entire country sinking.
I know what you’re thinking, but it is as plausible as global warming.