As for the rest of the US, the two areas that are highlighted as being perennially high-risk zones are the San Andreas Fault network around California, and something called the New Madrid Seismic Zone (NMSZ).
The NMSZ, centered on Tennessee, is a site of ancient mantle scars. They’re inactive, but large-scale stretching of North America is ripping them apart, which causes them to slip and generate earthquakes.
This 2017 map shows that this quake-related stretching appears to be on the rise – something which localized fracking certainly isn’t helping either.
California is well-known for being the most seismically treacherous part of the US to live in. The USGS recently estimated that there is essentially a 100 percent chance part or all of the fault network will shallowly rupture as a 6.7M event in the next three decades.
A truly devastating 7.5M event hitting LA has around a 30 percent chance of occurring in the same time frame, something that would easily qualify as the prophesized “big one.”
Rather remarkably, though, the USGS conclude that, in 2017, “the forecasted chance of damaging ground shaking in central Oklahoma is similar to that of natural earthquakes in high-hazard areas of California,” and that’s almost entirely down to fracking in the Middle America state.
Significant seismic events in 2015-2016 in these areas were almost always fracking-related. USGS