QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3md

Earthquake near Eureka, CA

No earthquake was likely felt in Eureka in the 24 hours to 9:13 pm PST (05:13 UTC). The last one was M 5.0, 128 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 Eureka

This page: a magnitude 2.3 earthquake was recorded 47 km (29 mi) east-southeast of Eureka, CA, at 10:16 am PDT on 24 June 2023 (17:16 UTC), 27 km deep.

USGS: 37km E of Hydesville, CA

10:16 am PDT, Jun 24, 2023 · · 27 km deep · released about 91 lb of TNT

10 km30 km60 km120 km N Humboldt County 25 kmTrinity County 47 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
10:16 am PDT on 24 June 2023 ()
Where
47 km (29 mi) east-southeast of Eureka, CA · earthquakes near Eureka
Magnitude
M 2.3 (md)
Depth
27 km below the surface
Felt
no reports yet
Nearest
Humboldt County, 25 km WNW
Nearest mapped fault
Little Salmon fault, 20 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 1234 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 Eureka, 47 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 91 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 170,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 120,000× the energy of this one
  3. Around the size people start to feel M 3.0 10× the energy of this one
  4. This earthquake M 2.3 about 91 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 5.3 on 2023-01-01 — about 35,000 times the energy of this one.

Before 2016, the USGS record lists 9 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 The 1954 Eureka-Arcata, California Earthquake · 33 km NW of this epicentre
  2. 6.0 Near Rio Dell, California · 46 km WSW of this epicentre
  3. 5.8 Near Eureka, California · 36 km NW of this epicentre
  4. 5.6 15 km SW of Burnt Ranch, California · 13 km NNE of this epicentre
  5. 5.4 3 km NNW of Burnt Ranch, California · 30 km NNE 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 40.6025, -123.6678. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Humboldt County, CA 25 km (15 mi) WNW earthquakes near Humboldt County
Trinity County, CA 47 km (29 mi) E earthquakes near Trinity County
Siskiyou County, CA 145 km (90 mi) NE earthquakes near Siskiyou County
Glenn County, CA 155 km (96 mi) SE earthquakes near Glenn 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. 3.2 35 km S of Willow Creek, CA
  2. 1.7 26 km E of Hydesville, CA
  3. 2.1 14 km N of Hayfork, CA
  4. 1.6 31 km W of Hayfork, CA
  5. 2.4 33 km W of Hayfork, CA
  6. 2.0 10 km ESE of Blue Lake, CA
  7. 1.7 25 km NE of Redway, CA
  8. 1.7 15 km E of Petrolia, CA
  9. 2.8 19 km E of Petrolia, CA
  10. 3.0 19 km E of Petrolia, CA
  11. 2.1 18 km SSE of Rio Dell, CA
  12. 4.8 20 km E of Petrolia, CA
  13. 1.7 4 km ESE of Fortuna, CA
  14. 1.6 28 km E of Hydesville, CA
  15. 2.0 27 km E of Hydesville, 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.