QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

15km S of Willow Creek, CA

· 9.4 km deep · released about 38 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Humboldt County 27 kmTrinity County 47 kmDel Norte County 109 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
9.4 km below the surface
Felt
no reports yet
Nearest
Humboldt County, 27 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3223 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 38 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 5.8 390,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 280,000× the energy of this one
  3. Around the size people start to feel M 3.0 25× the energy of this one
  4. This earthquake M 2.1 about 38 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 40.8043, -123.6342. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Humboldt County, CA 27 km (17 mi) ENE of here earthquakes near Humboldt County
Trinity County, CA 47 km (29 mi) WNW of here earthquakes near Trinity County
Del Norte County, CA 109 km (68 mi) SSE of here earthquakes near Del Norte County
Siskiyou County, CA 127 km (79 mi) SW of here earthquakes near Siskiyou County
Tehama County, CA 141 km (87 mi) WNW of here earthquakes near Tehama 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. 2.2 6km NNE of Hydesville, CA
  2. 2.1 6km NNE of Hydesville, CA
  3. 2.7 6km NNE of Hydesville, CA
  4. 1.9 24km SSE of Blue Lake, CA
  5. 2.1 13km WSW of Hayfork, CA
  6. 1.7 13km ESE of Hydesville, CA
  7. 1.8 13km ESE of Hydesville, CA
  8. 3.2 15km NE of Westhaven-Moonstone, CA
  9. 2.1 6km E of Fortuna, CA
  10. 2.0 14km WNW of Willow Creek, CA
  11. 1.9 2km SW of Arcata, CA
  12. 2.3 28km W of Hayfork, CA
  13. 2.4 28km W of Hayfork, CA
  14. 1.8 15km SE of Blue Lake, CA
  15. 1.7 2km SSE 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.8 on 2016-07-21 — it released about 13,000 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.