QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

Earthquake near Hayfork, CA

No earthquake was likely felt in Hayfork in the 24 hours to 9:59 pm PST (05:59 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 1.7 earthquake was recorded 33 km (20 mi) west-southwest of Hayfork, CA, at 4:14 am PDT on 27 June 2024 (11:14 UTC), 2.3 km deep.

USGS: 33 km W of Hayfork, CA

4:14 am PDT, Jun 27, 2024 · · 2.3 km deep · released about 10 lb of TNT

10 km30 km60 km120 km N Humboldt County 39 kmTrinity County 42 kmMendocino County 118 kmTehama County 120 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
4:14 am PDT on 27 June 2024 ()
Where
33 km (20 mi) west-southwest of Hayfork, CA · earthquakes near Hayfork
Magnitude
M 1.7 (md)
Depth
2.3 km below the surface
Felt
no reports yet
Nearest
Humboldt County, 39 km NW
Nearest mapped fault
Little Salmon fault, 22 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 867 days ago

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

At this magnitude and depth, people at rest would likely notice it out to about 12 km (7 mi) from the epicentre. In Hayfork, 33 km away, the estimate is intensity I (not felt). 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 10 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 92× the energy of this one
  4. This earthquake M 1.7 about 10 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 310,000 times the energy of this one.

Before 2016, the USGS record lists 4 earthquakes of M5 or more within 50 km:

  1. 6.4 The 1954 Eureka-Arcata, California Earthquake · 48 km NW of this epicentre
  2. 5.6 15 km SW of Burnt Ranch, California · 25 km N of this epicentre
  3. 5.4 3 km NNW of Burnt Ranch, California · 39 km N of this epicentre
  4. 5.0 2 km E of Rio Dell, California · 44 km W 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 40.4920, -123.5630. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Humboldt County, CA 39 km (24 mi) NW earthquakes near Humboldt County
Trinity County, CA 42 km (26 mi) ENE earthquakes near Trinity County
Mendocino County, CA 118 km (73 mi) S earthquakes near Mendocino County
Tehama County, CA 120 km (75 mi) ESE earthquakes near Tehama County
Glenn County, CA 140 km (87 mi) SE earthquakes near Glenn County

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

Aftershocks so far

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

  1. 2.6 16 km NNE of Redway, CA
  2. 2.5 17 km NNE of Redway, CA
  3. 3.3 16 km NNE of Redway, CA
  4. 4.0 20 km NE of Redway, CA
  5. 2.1 6 km SE of Redway, CA
  6. 2.3 18 km N of Redway, CA
  7. 2.3 21 km NNE of Redway, CA
  8. 2.3 28 km ESE of Rio Dell, CA
  9. 2.4 22 km ESE of Hydesville, CA
  10. 2.9 17 km N of Redway, CA
  11. 2.2 12 km ENE of Hayfork, CA
  12. 2.0 11 km ESE of Blue Lake, CA
  13. 1.6 30 km W of Hayfork, CA
  14. 2.4 18 km SSE of Rio Dell, CA
  15. 1.9 3 km NW 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.