QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9md

Earthquake near Pine Hills, CA

No earthquake was likely felt in Pine Hills in the 24 hours to 3:31 am PST (11:31 UTC). The last one was M 5.0, 126 km (79 mi) WSW, at 8:56 pm PST on 4 November 2026, estimated intensity II (weak) in town; 145 felt reports to USGS. Every earthquake near Pine Hills

This page: a magnitude 2.9 earthquake was recorded 14 km (9 mi) east-southeast of Pine Hills, CA, at 4:26 am PDT on 1 August 2025 (11:26 UTC), 26 km deep. 14 people have reported feeling it to USGS.

USGS: 14 km SE of Pine Hills, CA

4:26 am PDT, Aug 1, 2025 · · 26 km deep · released about 650 lb of TNT

Every earthquake near Pine Hills Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Humboldt County 7 kmTrinity County 75 kmDel Norte County 119 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
4:26 am PDT on 1 August 2025 ()
Where
14 km (9 mi) east-southeast of Pine Hills, CA · earthquakes near Pine Hills
Magnitude
M 2.9 (md)
Depth
26 km below the surface
Felt
14 reports · strongest reported intensity III
Nearest
Humboldt County, 7 km ENE
Nearest mapped fault
Mad River fault, 5 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 391 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 18 km (11 mi) from the epicentre. In Pine Hills, 14 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.

Likely felt in: Fortuna 16 km, intensity II · Humboldt Hill 17 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 21 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.2 The 1992 Petrolia, California Earthquake · 43 km SSW of this epicentre
  2. 6.5 The 1932 Eureka, California Earthquake · 25 km WNW of this epicentre
  3. 6.4 The 1954 Eureka-Arcata, California Earthquake · 20 km NNE of this epicentre
  4. 6.0 Near Rio Dell, California · 26 km SW of this epicentre
  5. 5.8 Near Eureka, California · 13 km N 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 40.6805, -123.9977. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Humboldt County, CA 7 km (4 mi) ENE earthquakes near Humboldt County
Trinity County, CA 75 km (46 mi) E earthquakes near Trinity County
Del Norte County, CA 119 km (74 mi) N earthquakes near Del Norte County

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

Aftershocks so far

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

  1. 1.6 13 km WSW of Ferndale, CA
  2. 2.1 16 km SSE of Rio Dell, CA
  3. 1.8 22 km E of Petrolia, CA
  4. 1.8 18 km WSW of Ferndale, CA
  5. 2.8 23 km WSW of Ferndale, CA
  6. 2.8 21 km WSW of Ferndale, CA
  7. 1.8 17 km WSW of Ferndale, CA
  8. 1.9 18 km WSW of Ferndale, CA
  9. 2.0 11 km SSW of Willow Creek, CA
  10. 3.4 9 km ESE of Willow Creek, CA
  11. 2.0 14 km WNW of Willow Creek, CA
  12. 1.7 22 km E of Hydesville, CA
  13. 2.0 11 km W of Bayview, CA
  14. 2.3 26 km W of Humboldt Hill, CA
  15. 2.1 3 km SSE of Fortuna, 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.