o7
Some shallow strong EQs off the coast of northern California.
Note depth: 2.2 km
https://earthquake.usgs.gov/earthquakes/map/
I wonder if this correlates with a tunnel location.
M 5.8 - 86km W of Petrolia, CA
2020-03-09 02:59:06 (UTC)40.402°N 125.295°W2.2 km depth
M 4.9 - 92km W of Petrolia, CA
2020-03-09 06:32:57 (UTC)40.398°N 125.371°W2.2 km depth
& others of lesser magnitude