QuakeIndex

Earthquake · reviewed by a seismologist

M 3.5ml

17km E of Ocotillo, CA

· 12 km deep · released about 2.3 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Imperial County 57 kmSan Diego County 96 kmRiverside County 115 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 3.5 (ml)
Depth
12 km below the surface
Felt
9 reports · strongest reported intensity IV
Measured shaking
intensity III (ShakeMap)
Nearest
Imperial County, 57 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1855 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 9 people have reported feeling it to USGS.

How big was it?

This earthquake released about 2.3 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.5 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 75,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 3,300× the energy of this one
  3. Magna, Utah 2020 M 5.7 2,400× the energy of this one
  4. This earthquake M 3.5 about 2.3 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 4.7× 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 32.7073, -115.8193. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Imperial County, CA 57 km (35 mi) SW of here earthquakes near Imperial County
San Diego County, CA 96 km (60 mi) ESE of here earthquakes near San Diego County
Riverside County, CA 115 km (71 mi) S of here earthquakes near Riverside County

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

Aftershocks so far

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

  1. 1.7 7km NNE of Westmorland, CA
  2. 1.5 15km ENE of Ocotillo, CA
  3. 1.6 2km ENE of Westmorland, CA
  4. 2.2 2km ENE of Westmorland, CA
  5. 1.8 2km ENE of Westmorland, CA
  6. 1.7 4km SW of Progreso, B.C., MX
  7. 1.6 19km NNE of Ocotillo, CA
  8. 1.7 16km E of Ocotillo, CA
  9. 1.7 8km WNW of Holtville, CA
  10. 1.7 25km WSW of Westmorland, CA
  11. 1.6 8km W of Holtville, CA
  12. 2.2 8km W of Holtville, CA
  13. 2.9 8km W of Holtville, CA
  14. 1.9 8km WNW of Holtville, CA
  15. 2.2 8km WNW of Holtville, 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 4.9 on 2020-10-01 — it released about 170 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.