QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

36 km S of Willow Creek, CA

· 25 km deep · released about 40 lb of TNT

10 km30 km60 km120 km N Humboldt County 29 kmTrinity County 42 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 2.1 (md)
Depth
25 km below the surface
Felt
2 reports · strongest reported intensity III
Nearest
Humboldt County, 29 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 405 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 2 people have reported feeling it to USGS.

How big was it?

This earthquake released about 40 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 380,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 270,000× the energy of this one
  3. Around the size people start to feel M 3.0 24× the energy of this one
  4. This earthquake M 2.1 about 40 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 40.6148, -123.6058. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Humboldt County, CA 29 km (18 mi) ESE of here earthquakes near Humboldt County
Trinity County, CA 42 km (26 mi) W of here earthquakes near Trinity County
Tehama County, CA 128 km (80 mi) WNW of here earthquakes near Tehama County
Siskiyou County, CA 141 km (87 mi) SW of here earthquakes near Siskiyou County
Glenn County, CA 152 km (95 mi) NW of here earthquakes near Glenn County

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

Aftershocks so far

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

  1. 2.1 7 km E of Fortuna, CA
  2. 2.1 19 km E of Hydesville, CA
  3. 2.3 4 km NNE of Hayfork, CA
  4. 1.8 33 km SW of Hayfork, CA
  5. 3.0 16 km ENE of Hydesville, CA
  6. 2.4 20 km ENE of Willow Creek, CA
  7. 1.9 8 km E of Hydesville, CA
  8. 1.9 35 km NE of Redway, CA
  9. 1.8 20 km NE of Hydesville, CA
  10. 2.0 10 km S of Rio Dell, CA
  11. 1.7 35 km E of Hydesville, CA
  12. 2.3 22 km NNE of Redway, CA
  13. 1.6 13 km NE of Hydesville, CA
  14. 1.5 18 km SSE of Rio Dell, CA
  15. 2.4 28 km ESE of Rio Dell, 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 5.3 on 2023-01-01 — it released about 80,000 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.