QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

28km SE of Redway, CA

· -0.1 km deep · released about 13 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mendocino County 58 kmTrinity County 88 kmHumboldt County 90 kmGlenn County 108 kmTehama County 117 kmLake County 118 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 1.8 (md)
Depth
-0.1 km below the surface
Felt
no reports yet
Nearest
Mendocino County, 58 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3000 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 13 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 810,000× the energy of this one
  3. Around the size people start to feel M 3.0 72× the energy of this one
  4. This earthquake M 1.8 about 13 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 39.9438, -123.5852. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 58 km (36 mi) NNW of here earthquakes near Mendocino County
Trinity County, CA 88 km (55 mi) SSW of here earthquakes near Trinity County
Humboldt County, CA 90 km (56 mi) SSE of here earthquakes near Humboldt County
Glenn County, CA 108 km (67 mi) WNW of here earthquakes near Glenn County
Tehama County, CA 117 km (73 mi) W of here earthquakes near Tehama County
Lake County, CA 118 km (73 mi) NW of here earthquakes near Lake County

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

Aftershocks so far

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

  1. 1.8 18km NNE of Redway, CA
  2. 1.8 4km E of Redway, CA
  3. 2.1 5km E of Redway, CA
  4. 1.8 5km NNW of Laytonville, CA
  5. 1.9 5km NNW of Laytonville, CA
  6. 2.7 33km SW of Hayfork, CA
  7. 2.0 13km S of Laytonville, CA
  8. 2.1 32km NNW of Covelo, CA
  9. 1.9 21km N of Laytonville, CA
  10. 1.9 29km NNE of Redway, CA
  11. 2.0 34km SW of Hayfork, CA
  12. 2.4 3km NW of Redway, CA
  13. 2.2 18km W of Cape Vizcaino, CA
  14. 1.8 13km SSE of Laytonville, CA
  15. 2.1 3km NNE of Redway, 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 4.3 on 2017-12-14 — it released about 5,600 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.