QuakeIndex

Earthquake · reviewed by a seismologist

M 4.6mw

99 km W of Trinidad, California

· 24 km deep · released about 110 tons of TNT

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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 4.6 (mw)
Depth
24 km below the surface
Felt
56 reports · strongest reported intensity II
Measured shaking
intensity II (ShakeMap)
USGS impact alert
green
Nearest
Humboldt County, 125 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3271 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 56 people have reported feeling it to USGS.

How big was it?

This earthquake released about 110 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.6 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 1,500× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 68× the energy of this one
  3. Magna, Utah 2020 M 5.7 48× the energy of this one
  4. This earthquake M 4.6 about 110 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 230× 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 41.0753, -125.3303. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Humboldt County, CA 125 km (78 mi) WNW of here earthquakes near Humboldt County
Del Norte County, CA 135 km (84 mi) WSW of here earthquakes near Del Norte County

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

Aftershocks so far

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

  1. 2.9 130 km W of Ferndale, California
  2. 2.5 104 km W of Big Lagoon, California
  3. 3.2 85km WNW of Ferndale, CA
  4. 2.5 98km W of Trinidad, CA
  5. 2.8 112km W of Ferndale, CA
  6. 2.9 144km WNW of Trinidad, CA
  7. 2.8 136km W of Trinidad, CA
  8. 3.0 96km WNW of Bayview, CA
  9. 3.0 102km WNW of Bayview, CA
  10. 3.2 97km W of Trinidad, CA
  11. 4.1 94km W of Trinidad, CA
  12. 2.9 104km W of Trinidad, CA
  13. 2.5 84km WNW of Ferndale, CA
  14. 3.6 99km W of Trinidad, CA
  15. 2.9 76 km W of Big Lagoon, California

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 5.1 on 2017-07-29 — it released about 5.6 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.