FORT BRAGG, 3/11/23 — Mendocino Coast residents felt a quick shake this morning, but had trouble finding information about it on the usual earthquake reporting places. The Caltech Southern California Earthquake Center has a report of a micro earthquake at 8:18:21 AM on Saturday, March 11, 2023:
“The magnitude 2.3 event occurred 11 km (7 miles) WSW of Fort Bragg, CA. The hypocentral depth is -0.16 km (-0.1 miles). “
See the Caltech report here: https://scedc.caltech.edu/recent/Quakes/nc73855410.html
Barbara Barkovich said the shaker lasted one tenth of a second at her house.
“It was just a very short movement, sort of like when a bird (unfortunately) flies into your window. I didn’t see it on USGS either.”
Margaret Roberts of Mendocino had been wondering what that noise was.
“So that’s what that noise was! I didn’t feel it, but I heard a brief sound like a loud crash.”
Elise King got a sharp jolt in her wood frame house right by the ocean in Caspar South.
“I felt it as a sharp brief jolt. I could tell by the sharp impact without any rolling that it was a nearby earthquake. Being a 2.3, I only felt it because it was so close. Interestingly, I could tell from the motion exactly in what direction the earthquake was centered. It felt like a car had backed into my house.
She could tell the direction the quake was in by the way it felt, having experience with quakes in the past.
“When I lived in Berkeley we frequently had these small quakes centered in my neighborhood up on the hill. A quick medium jolt indicates a small quake nearby. Long rolling movements indicate a bigger quake many miles away, as I experienced in the 1989 Loma Prieta quake. The longer the duration of movement, the larger the quake.”
Mike Sears said it rocked the dock in Noyo Harbor.
USGS still has the quake as an unknown event. Anyone who felt it can report it here.
USGS DID record the event.
It was a 2.3 right on the fault line offshore of Caspar. The USGS default map only shows the 2.5’s and up.
To select ‘all magnitudes’, click on the little ‘gear’ at the top right to select that and other map settings.
Here is a link to the USGS Earthquake Map with the map set to ‘all magnitudes’.
As you can see, at that low magnitude setting, California and Alaska are always VERY active.