QuakeIndex

Earthquake · reviewed by a seismologist

M 3.9mw

13km NNE of Thousand Palms, CA

· 8.3 km deep · released about 9.6 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Riverside County 36 kmSan Bernardino County 105 kmSan Diego County 108 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 3.9 (mw)
Depth
8.3 km below the surface
Felt
1263 reports · strongest reported intensity IV
Measured shaking
intensity VI (ShakeMap)
Nearest
Riverside County, 36 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2984 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 1263 people have reported feeling it to USGS.

How big was it?

This earthquake released about 9.6 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.9 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 18,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 790× the energy of this one
  3. Magna, Utah 2020 M 5.7 560× the energy of this one
  4. This earthquake M 3.9 about 9.6 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 20× 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 33.9210, -116.3217. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Riverside County, CA 36 km (23 mi) NW of here earthquakes near Riverside County
San Bernardino County, CA 105 km (65 mi) S of here earthquakes near San Bernardino County
San Diego County, CA 108 km (67 mi) NNE of here earthquakes near San Diego County
Imperial County, CA 133 km (82 mi) NW of here earthquakes near Imperial County

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

Aftershocks so far

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

  1. 2.2 11km NNE of Thousand Palms, CA
  2. 1.7 21km N of North Shore, CA
  3. 2.6 6km SW of Idyllwild, CA
  4. 1.5 9km SSW of Idyllwild, CA
  5. 1.9 11km N of Cabazon, CA
  6. 1.9 10km SSW of Idyllwild, CA
  7. 1.6 10km N of Cabazon, CA
  8. 2.6 11km N of Cabazon, CA
  9. 1.8 12km N of Cabazon, CA
  10. 1.6 11km N of Cabazon, CA
  11. 2.4 11km N of Cabazon, CA
  12. 1.8 11km N of Cabazon, CA
  13. 2.5 9km N of Cabazon, CA
  14. 2.4 9km N of Cabazon, CA
  15. 1.7 12km N of Cabazon, 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.

On USGS

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