QuakeIndex

Earthquake · automatic estimate, may change

M 2.9ml

Earthquake near Ferndale, CA

No earthquake was likely felt in Ferndale in the 24 hours to 3:33 am PST (11:33 UTC). The last one was M 5.0, 113 km (70 mi) W, at 8:56 pm PST on 4 November 2026, estimated intensity III (weak) in town; 145 felt reports to USGS. Every earthquake near Ferndale

This page: a magnitude 2.9 earthquake was recorded 11 km (7 mi) south of Ferndale, CA, at 5:06 pm PST on 21 December 2025 (01:06 UTC), 5.1 km deep. 1 person has reported feeling it to USGS. The magnitude and location are an automatic first estimate and may change.

USGS: 11 km S of Ferndale, CA

5:06 pm PST, Dec 21, 2025 · · 5.1 km deep · released about 650 lb of TNT

Every earthquake near Ferndale Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Humboldt County 38 kmTrinity County 98 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
5:06 pm PST on 21 December 2025 ()
Where
11 km (7 mi) south of Ferndale, CA · earthquakes near Ferndale
Magnitude
M 2.9 (ml)
Depth
5.1 km below the surface
Felt
1 report · strongest reported intensity III
Nearest
Humboldt County, 38 km NE
Nearest mapped fault
Little Salmon fault, 17 km from its surface trace — near is not the same as on
Status
Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS · we first saw it 238 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, people at rest would likely notice it out to about 31 km (19 mi) from the epicentre. In Ferndale, 11 km away, the estimate is intensity III (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.

Likely felt in: Ferndale 11 km, intensity III · Rio Dell 12 km, intensity III · Fortuna 16 km, intensity II · Humboldt Hill 28 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 650 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 23,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 16,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.5× the energy of this one
  4. This earthquake M 2.9 about 650 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 6.4 on 2022-12-20 — about 180,000 times the energy of this one.

Before 2016, the USGS record lists 38 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.2 The 1992 Petrolia, California Earthquake · 16 km S of this epicentre
  2. 6.6 32 km SW of Ferndale, California · 28 km WSW of this epicentre
  3. 6.5 The 1932 Eureka, California Earthquake · 28 km N of this epicentre
  4. 6.5 30 km WSW of Ferndale, California · 27 km W of this epicentre
  5. 6.5 The 2010 Eureka, California Earthquake · 42 km WNW 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 40.4763, -124.2508. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Humboldt County, CA 38 km (23 mi) NE earthquakes near Humboldt County
Trinity County, CA 98 km (61 mi) ENE earthquakes near Trinity County
Mendocino County, CA 135 km (84 mi) SSE earthquakes near Mendocino County

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

Aftershocks so far

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

  1. 2.2 9 km NNW of Eureka, CA
  2. 1.9 9 km NNW of Eureka, CA
  3. 2.4 8 km NNW of Eureka, CA
  4. 2.4 2 km S of Humboldt Hill, CA
  5. 1.8 13 km WSW of Petrolia, CA
  6. 2.6 13 km NW of Ferndale, CA
  7. 1.8 18 km W of Petrolia, CA
  8. 1.7 12 km WNW of Petrolia, CA
  9. 1.8 20 km NE of Hydesville, CA
  10. 2.0 10 km S of Rio Dell, CA
  11. 1.7 16 km WSW of Petrolia, CA
  12. 2.2 16 km WSW of Petrolia, CA
  13. 2.6 27 km WNW of Petrolia, CA
  14. 2.6 21 km WSW of Petrolia, CA
  15. 2.7 11 km WSW of Rio Dell, 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.