QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0ml

37 km S of Hayfork, CA

· 40 km deep · released about 950 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Trinity County 47 kmTehama County 79 kmHumboldt County 85 kmMendocino County 91 kmGlenn County 94 kmShasta County 111 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
Magnitude
M 3.0 (ml)
Depth
40 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Trinity County, 47 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 98 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 950 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 350,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 16,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 11,000× the energy of this one
  4. This earthquake M 3.0 about 950 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.

Where

Epicentre 40.2228, -123.1495. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Trinity County, CA 47 km (29 mi) S of here earthquakes near Trinity County
Tehama County, CA 79 km (49 mi) W of here earthquakes near Tehama County
Humboldt County, CA 85 km (53 mi) SE of here earthquakes near Humboldt County
Mendocino County, CA 91 km (57 mi) NNE of here earthquakes near Mendocino County
Glenn County, CA 94 km (58 mi) NW of here earthquakes near Glenn County
Shasta County, CA 111 km (69 mi) WSW of here earthquakes near Shasta County

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

Aftershocks so far

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

  1. 1.7 30 km W of Hayfork, CA
  2. 1.6 16 km N of Covelo, CA
  3. 1.6 31 km W of Hayfork, CA
  4. 2.4 33 km W of Hayfork, CA
  5. 2.0 38 km NNW of Alder Springs, CA
  6. 1.7 25 km NE of Redway, CA
  7. 1.7 33 km SW of Hayfork, CA
  8. 1.7 16 km N of Covelo, CA
  9. 1.7 16 km N of Covelo, CA
  10. 1.5 34 km NE of Covelo, CA
  11. 2.1 15 km N of Covelo, CA
  12. 2.1 15 km N of Covelo, CA
  13. 2.3 15 km N of Covelo, CA
  14. 2.5 40 km NNE of Covelo, CA
  15. 2.0 15 km N of Covelo, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.5 on 2016-08-28 — it released about 170 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.