QuakeIndex

Earthquake · reviewed by a seismologist

M 6.2mw

7km N of Petrolia, CA

· 27 km deep · released about 30 kilotons of TNT

10 km30 km60 km120 km N Humboldt County 47 kmTrinity County 104 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 6.2 (mw)
Depth
27 km below the surface
Felt
4378 reports · strongest reported intensity VIII
Measured shaking
intensity VII (ShakeMap)
USGS impact alert
yellow
Tsunami
USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Nearest
Humboldt County, 47 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 279 days ago

This was a strong earthquake. Damage is likely near the epicentre and it is felt over a wide area. 4378 people have reported feeling it to USGS.

How big was it?

This earthquake released about 30 kilotons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 7.2 would have released about 32 times as much.

  1. Ridgecrest, California 2019 M 7.1 22× the energy of this one
  2. Loma Prieta, California 1989 M 6.9 11× the energy of this one
  3. Northridge, California 1994 M 6.7 5.6× the energy of this one
  4. This earthquake M 6.2 about 30 kilotons of TNT
  5. Mineral, Virginia 2011 M 5.8 this one released 4× more
  6. Magna, Utah 2020 M 5.7 this one released 5.6× more

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 40.3902, -124.2980. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Humboldt County, CA 47 km (29 mi) SW of here earthquakes near Humboldt County
Trinity County, CA 104 km (65 mi) WSW of here earthquakes near Trinity County
Mendocino County, CA 129 km (80 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

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

  1. 2.6 8km W of Petrolia, CA
  2. 1.9 4km NNE of Petrolia, CA
  3. 3.9 6km NE of Petrolia, CA
  4. 3.3 18km SW of Ferndale, CA
  5. 2.2 12km SSW of Ferndale, CA
  6. 2.3 12km SW of Rio Dell, CA
  7. 2.4 11km SSW of Ferndale, CA
  8. 2.4 11km NNE of Petrolia, CA
  9. 2.4 14km NNW of Petrolia, CA
  10. 3.2 11km NNE of Petrolia, CA
  11. 2.0 4km ENE of Petrolia, CA
  12. 2.6 12km SSW of Ferndale, CA
  13. 2.7 15km SW of Ferndale, CA
  14. 2.6 14km N of Petrolia, CA
  15. 3.3 13km SSW 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 5.7 on 2021-12-20.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.