QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Pine Hills, CA

No earthquake was likely felt in Pine Hills in the 24 hours to 9:07 am PST (17:07 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 1.8 earthquake was recorded 14 km (8 mi) east of Pine Hills, CA, at 8:32 pm PST on 10 December 2023 (04:32 UTC), 25 km deep.

USGS: 14 km E of Pine Hills, CA

8:32 pm PST, Dec 10, 2023 · · 25 km deep · released about 16 lb of TNT

10 km30 km60 km120 km N Humboldt County 6 kmTrinity County 74 kmDel Norte County 115 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
8:32 pm PST on 10 December 2023 ()
Where
14 km (8 mi) east of Pine Hills, CA · earthquakes near Pine Hills
Magnitude
M 1.8 (md)
Depth
25 km below the surface
Felt
no reports yet
Nearest
Humboldt County, 6 km ESE
Nearest mapped fault
Mad River fault, 3 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 1067 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. 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.

Earthquakes near other towns within 30 km: Cutten, Myrtletown, Bayside, Humboldt Hill, Eureka, Bayview.

How big was it?

This earthquake released about 16 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 930,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 660,000× the energy of this one
  3. Around the size people start to feel M 3.0 59× the energy of this one
  4. This earthquake M 1.8 about 16 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 7,400,000 times the energy of this one.

Before 2016, the USGS record lists 20 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.2 The 1980 Eureka, California Earthquake · 50 km NNW of this epicentre
  2. 7.2 The 1992 Petrolia, California Earthquake · 47 km SSW of this epicentre
  3. 6.5 The 1932 Eureka, California Earthquake · 25 km W of this epicentre
  4. 6.4 The 1954 Eureka-Arcata, California Earthquake · 17 km NNE of this epicentre
  5. 6.0 Near Rio Dell, California · 30 km SW 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 40.7175, -123.9923. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Humboldt County, CA 6 km (4 mi) ESE earthquakes near Humboldt County
Trinity County, CA 74 km (46 mi) E earthquakes near Trinity County
Del Norte County, CA 115 km (71 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

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

  1. 2.2 9 km WNW of Ferndale, CA
  2. 1.7 10 km S of Ferndale, CA
  3. 1.7 1 km WSW of Rio Dell, CA
  4. 1.5 3 km SSE of Ferndale, CA
  5. 1.6 4 km SW of Fortuna, CA
  6. 2.2 14 km WSW of Ferndale, CA
  7. 2.3 10 km SW of Ferndale, CA
  8. 1.6 14 km WSW of Ferndale, CA
  9. 1.6 4 km E of Fortuna, CA
  10. 1.6 9 km WSW of Rio Dell, CA
  11. 2.7 15 km NNW of Petrolia, CA
  12. 1.9 7 km W of Ferndale, CA
  13. 1.7 4 km ENE of Petrolia, CA
  14. 2.2 8 km SW of Ferndale, CA
  15. 1.7 30 km NNE of Redway, 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.