QuakeIndex

Earthquake · reviewed by a seismologist

M 2.7md

24km W of Petrolia, CA

· 25 km deep · released about 290 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Humboldt County 67 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
25 km below the surface
Felt
no reports yet
Nearest
Humboldt County, 67 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1330 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

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 40.3545, -124.5653. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Humboldt County, CA 67 km (41 mi) SW of here earthquakes near Humboldt County
Mendocino County, CA 140 km (87 mi) NW of here earthquakes near Mendocino 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. 2.1 5km ESE of Ferndale, CA
  2. 2.2 5km SE of Ferndale, CA
  3. 2.5 7km SW of Ferndale, CA
  4. 2.2 21km SW of Ferndale, CA
  5. 1.7 2km SW of Fortuna, CA
  6. 2.4 5km N of Hydesville, CA
  7. 1.7 6km SW of Ferndale, CA
  8. 2.8 15km WSW of Ferndale, CA
  9. 1.8 9km SW of Ferndale, CA
  10. 2.4 9km SW of Ferndale, CA
  11. 2.4 8km SW of Ferndale, CA
  12. 2.3 5km SW of Ferndale, CA
  13. 2.0 5km SE of Ferndale, CA
  14. 2.0 11km SW of Ferndale, CA
  15. 2.1 5km SW 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 6.2 on 2021-12-20 — it released about 200,000 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.