[Robert A Cook PE]

Problem is, these quakes (now over 68 in just 2 days, most of them over Mag 4) are on the side of the fault. The worst occur on the “front edge” of the moving tectonic plates, which are “fixed” very deep underground, but are now easier and able to move because the sides of the plates are loosened.

[saintgermaine]

Thanks for the explanation. Stay safe...