QuakeIndex

Earthquake · reviewed by a seismologist

M 2.7md

21km SE of Blue Lake, CA

· 19 km deep · released about 290 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Humboldt County 8 kmTrinity County 62 kmDel Norte County 114 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 2.7 (md)
Depth
19 km below the surface
Felt
3 reports · strongest reported intensity III
Nearest
Humboldt County, 8 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1307 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 3 people have reported feeling it to USGS.

How big was it?

This earthquake released about 290 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 51,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 36,000× the energy of this one
  3. Around the size people start to feel M 3.0 3.2× the energy of this one
  4. This earthquake M 2.7 about 290 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 40.7292, -123.8398. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Humboldt County, CA 8 km (5 mi) ENE of here earthquakes near Humboldt County
Trinity County, CA 62 km (38 mi) W of here earthquakes near Trinity County
Del Norte County, CA 114 km (71 mi) S of here earthquakes near Del Norte County
Siskiyou County, CA 145 km (90 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

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

  1. 2.3 5km ESE of Hydesville, CA
  2. 2.5 10km NE of Hydesville, CA
  3. 2.5 3km SSW of Fortuna, CA
  4. 2.3 3km SE of Ferndale, CA
  5. 2.2 10km NNE of Hydesville, CA
  6. 2.2 5km SE of Ferndale, CA
  7. 2.4 7km WSW of Ferndale, CA
  8. 2.7 3km ENE of Hydesville, CA
  9. 1.8 9km E of Hydesville, CA
  10. 2.0 7km SW of Ferndale, CA
  11. 1.7 14km ENE of Hydesville, CA
  12. 1.8 2km NW of Hydesville, CA
  13. 2.6 7km SW of Ferndale, CA
  14. 1.8 6km SW of Ferndale, CA
  15. 4.3 6km WSW of Ferndale, 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 4.9 on 2022-12-20 — it released about 2,500 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.