QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

29km W of Hayfork, CA

· 8.3 km deep · released about 25 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Trinity County 37 kmHumboldt County 39 kmTehama County 119 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 1.9 (md)
Depth
8.3 km below the surface
Felt
no reports yet
Nearest
Trinity County, 37 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2785 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 25 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.0 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 420,000× the energy of this one
  3. Around the size people start to feel M 3.0 38× the energy of this one
  4. This earthquake M 1.9 about 25 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 40.5328, -123.5273. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Trinity County, CA 37 km (23 mi) WSW of here earthquakes near Trinity County
Humboldt County, CA 39 km (24 mi) ESE of here earthquakes near Humboldt County
Tehama County, CA 119 km (74 mi) WNW of here earthquakes near Tehama County
Glenn County, CA 141 km (88 mi) NW of here earthquakes near Glenn County
Siskiyou County, CA 144 km (89 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

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

  1. 1.5 4km N of Redway, CA
  2. 1.9 10km SE of Rio Dell, CA
  3. 1.8 29km N of Redway, CA
  4. 2.1 13km SE of Rio Dell, CA
  5. 1.8 20km SSE of Rio Dell, CA
  6. 1.7 17km ENE of Hydesville, CA
  7. 3.2 13km ESE of Blue Lake, CA
  8. 2.0 8km E of Hydesville, CA
  9. 3.0 27km WNW of Hayfork, CA
  10. 2.4 17km SE of Willow Creek, CA
  11. 2.1 16km ENE of Hydesville, CA
  12. 2.8 16km SSE of Rio Dell, CA
  13. 2.0 11km WNW of Hayfork, CA
  14. 2.0 11km WNW of Hayfork, CA
  15. 1.6 30km S of Willow Creek, 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 19,000 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.