QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

27km SE of Hayfork, CA

· 5.2 km deep · released about 38 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Trinity County 34 kmTehama County 69 kmHumboldt County 88 kmShasta County 91 kmGlenn County 98 kmMendocino County 110 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
5.2 km below the surface
Felt
no reports yet
Nearest
Trinity County, 34 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2023 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 40.3588, -122.9855. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Trinity County, CA 34 km (21 mi) SSE of here earthquakes near Trinity County
Tehama County, CA 69 km (43 mi) WNW of here earthquakes near Tehama County
Humboldt County, CA 88 km (55 mi) ESE of here earthquakes near Humboldt County
Shasta County, CA 91 km (57 mi) WSW of here earthquakes near Shasta County
Glenn County, CA 98 km (61 mi) NNW of here earthquakes near Glenn County
Mendocino County, CA 110 km (68 mi) NNE of here earthquakes near Mendocino County

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

Aftershocks so far

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

  1. 2.1 40km NE of Covelo, CA
  2. 3.0 37 km S of Hayfork, CA
  3. 2.2 20km WSW of Hayfork, CA
  4. 2.3 25km WNW of Red Bluff, CA
  5. 1.8 36km NE of Covelo, CA
  6. 4.3 36km NE of Redway, CA
  7. 2.2 17km S of Weaverville, CA
  8. 2.1 33km WNW of Rancho Tehama Reserve, CA
  9. 2.0 32km WNW of Rancho Tehama Reserve, CA
  10. 2.7 31km NW of Rancho Tehama Reserve, CA
  11. 2.0 40km SSW of Hayfork, CA
  12. 2.5 27km WSW of Hayfork, CA
  13. 2.0 44km NW of Rancho Tehama Reserve, CA
  14. 1.8 40km NW of Rancho Tehama Reserve, CA
  15. 2.6 6km NNW of Hayfork, 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 4,300 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.