QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0ml

Earthquake near Hayfork, CA

No earthquake was likely felt in Hayfork in the 24 hours to 5:07 am PST (13:07 UTC). The last one was M 3.7, 42 km (26 mi) W, at 2:44 pm PDT on 7 September 2026, estimated intensity II (weak) in town; 15 felt reports to USGS. Every earthquake near Hayfork

This page: a magnitude 3.0 earthquake was recorded 37 km (23 mi) south of Hayfork, CA, at 9:41 am PST on 14 February 2023 (17:41 UTC), 40 km deep. 1 person has reported feeling it to USGS.

USGS: 37 km S of Hayfork, CA

9:41 am PST, Feb 14, 2023 · · 40 km deep · released about 950 lb of TNT

10 km30 km60 km120 km N Trinity County 47 kmTehama County 79 kmHumboldt County 85 kmMendocino County 91 kmGlenn County 94 kmShasta County 111 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
9:41 am PST on 14 February 2023 ()
Where
37 km (23 mi) south of Hayfork, CA · earthquakes near Hayfork
Magnitude
M 3.0 (ml)
Depth
40 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Trinity County, 47 km N
Nearest mapped fault
Bartlett Springs fault system, 23 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 144 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Hayfork, 37 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

How big was it?

This earthquake released about 950 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 350,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 16,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 11,000× the energy of this one
  4. This earthquake M 3.0 about 950 lb of TNT

Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.

For this area

The largest earthquake within 50 km since 2016 was M 4.5 on 2016-08-28 — about 170 times the energy of this one.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.5 33 km NW of Rancho Tehama Reserve, California · 37 km E of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 40.2228, -123.1495. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Trinity County, CA 47 km (29 mi) N earthquakes near Trinity County
Tehama County, CA 79 km (49 mi) E earthquakes near Tehama County
Humboldt County, CA 85 km (53 mi) NW earthquakes near Humboldt County
Mendocino County, CA 91 km (57 mi) SSW earthquakes near Mendocino County
Glenn County, CA 94 km (58 mi) SE earthquakes near Glenn County
Shasta County, CA 111 km (69 mi) ENE earthquakes near Shasta County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

44 earthquakes have been recorded within 50 km since this one.

  1. 1.7 30 km W of Hayfork, CA
  2. 1.6 16 km N of Covelo, CA
  3. 1.6 31 km W of Hayfork, CA
  4. 2.4 33 km W of Hayfork, CA
  5. 2.0 38 km NNW of Alder Springs, CA
  6. 1.7 25 km NE of Redway, CA
  7. 1.7 33 km SW of Hayfork, CA
  8. 1.7 16 km N of Covelo, CA
  9. 1.7 16 km N of Covelo, CA
  10. 1.5 34 km NE of Covelo, CA
  11. 2.1 15 km N of Covelo, CA
  12. 2.1 15 km N of Covelo, CA
  13. 2.3 15 km N of Covelo, CA
  14. 2.5 40 km NNE of Covelo, CA
  15. 2.0 15 km N of Covelo, CA

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.