QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

23km SSW of Willow Creek, CA

· 29 km deep · released about 41 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Humboldt County 20 kmTrinity County 50 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
Magnitude
M 2.1 (md)
Depth
29 km below the surface
Felt
no reports yet
Nearest
Humboldt County, 20 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2195 days ago

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

How big was it?

This earthquake released about 41 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 5.8 370,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 260,000× the energy of this one
  3. Around the size people start to feel M 3.0 23× the energy of this one
  4. This earthquake M 2.1 about 41 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 40.7420, -123.6953. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Humboldt County, CA 20 km (12 mi) ENE of here earthquakes near Humboldt County
Trinity County, CA 50 km (31 mi) WNW of here earthquakes near Trinity County
Del Norte County, CA 115 km (71 mi) SSE of here earthquakes near Del Norte County
Siskiyou County, CA 135 km (84 mi) SW of here earthquakes near Siskiyou County

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

Aftershocks so far

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

  1. 2.1 32km W of Hayfork, CA
  2. 2.8 15km WNW of Willow Creek, CA
  3. 2.1 30km NE of Redway, CA
  4. 1.6 35km E of Hydesville, CA
  5. 2.2 3km NW of Willow Creek, CA
  6. 2.5 31km WNW of Weaverville, CA
  7. 2.7 1km NNE of Humboldt Hill, CA
  8. 2.2 7km NNW of Hayfork, CA
  9. 1.8 35km S of Willow Creek, CA
  10. 1.9 29km NE of Redway, CA
  11. 1.8 27km SSE of Blue Lake, CA
  12. 2.1 24km ESE of Willow Creek, CA
  13. 2.4 34km E of Hydesville, CA
  14. 2.2 34km E of Hydesville, CA
  15. 2.2 4km NW of Humboldt Hill, 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 4.8 on 2016-07-21 — it released about 12,000 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.