QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

5km SSE of Lake Henshaw, CA

· 6.0 km deep · released about 16 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Diego County 20 kmRiverside County 91 kmOrange County 110 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 (ml)
Depth
6.0 km below the surface
Felt
no reports yet
Nearest
San Diego County, 20 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2140 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 16 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 5.8 970,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 680,000× the energy of this one
  3. Around the size people start to feel M 3.0 61× the energy of this one
  4. This earthquake M 1.8 about 16 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 33.1993, -116.7442. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
San Diego County, CA 20 km (12 mi) N of here earthquakes near San Diego County
Riverside County, CA 91 km (56 mi) SW of here earthquakes near Riverside County
Orange County, CA 110 km (68 mi) ESE of here earthquakes near Orange County

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

Aftershocks so far

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

  1. 2.0 13km WNW of Anza, CA
  2. 2.1 20km ESE of Anza, CA
  3. 1.6 8km N of Borrego Springs, CA
  4. 1.6 17km ESE of Julian, CA
  5. 2.3 16km ESE of Julian, CA
  6. 1.7 20km ESE of Julian, CA
  7. 1.7 20km ESE of Julian, CA
  8. 1.5 12km NW of Ocotillo Wells, CA
  9. 1.9 10km ENE of Borrego Springs, CA
  10. 1.9 6km W of Palomar Observatory, CA
  11. 2.1 8km NE of Aguanga, CA
  12. 2.1 17km ESE of Julian, CA
  13. 1.8 8km WNW of Lake Henshaw, CA
  14. 1.5 8km ENE of Aguanga, CA
  15. 1.6 9km E of San Diego Country Estates, 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 5.2 on 2016-06-10 — it released about 120,000 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.