Does seem odd. California people, ever have an off shore earthquake? I mean I know with underwater volcanic activity it’s possible. But has that ever happened off the coast of LA?
Not sure, I left after the SF quake and stopped tracking such things. Am sure someone here keeps up with the data.
http://temblor.net/earthquake-insights/m5-3-earthquake-strikes-offshore-southern-california-6741/
Geophysicist Mark Legg commented, “About every six years there’s been a M5+ offshore southern California. There was a M=6.0 in 1981 nearby. In this intersection area, which marks the boundary between the inner and outer continental borderland, there are many faults. The Santa Cruz Basin itself was ripped from Baja California and shoved northwest by the San Andreas shear zone. The Basin is ramming into the Transverse Ranges, marked by the Santa Cruz and Santa Rosa Islands, which have been caught in the shear zone and spun like ball bearings.
“Does seem odd. California people, ever have an off shore earthquake?”
Yes.
I'm still waiting for Arizona to turn into beachfront property.
Yes, earthquakes commonly happen offshore. For example, the big tsunami that killed over 200,000 people in Southeast Asia in 2004 happened under water. Earthquakes typically originate miles under the surface of the earth, and they can happen under land or under water.
It just depends where the fault is.
The Long Beach Earthquake in 1933 was off shore and quite large. ~ 6.5.
True story, Albert Einstein was visiting Dr. Richter when the Long Beach quake hit.