QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1ml

21km SSW of San Pedro, CA

· 8.7 km deep · released about 47 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 54 kmLos Angeles County 72 kmVentura County 116 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 2.1 (ml)
Depth
8.7 km below the surface
Felt
no reports yet
Nearest
Orange County, 54 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1620 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 47 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 320,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 230,000× the energy of this one
  3. Around the size people start to feel M 3.0 20× the energy of this one
  4. This earthquake M 2.1 about 47 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 33.5535, -118.3408. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Orange County, CA 54 km (34 mi) WSW of here earthquakes near Orange County
Los Angeles County, CA 72 km (45 mi) S of here earthquakes near Los Angeles County
Ventura County, CA 116 km (72 mi) SE of here earthquakes near Ventura County

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

Aftershocks so far

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

  1. 1.5 1km SSW of View Park-Windsor Hills, CA
  2. 1.6 3km S of Westminster, CA
  3. 1.5 4km S of Westminster, CA
  4. 1.9 17km NE of Avalon, CA
  5. 1.8 19km NNE of Avalon, CA
  6. 1.8 8km SE of San Pedro, CA
  7. 2.2 22km SSW of Newport Beach, CA
  8. 2.9 4km W of Manhattan Beach, CA
  9. 1.7 1km SSE of Carson, CA
  10. 1.8 4km W of Seal Beach, CA
  11. 2.5 20km S of San Pedro, CA
  12. 2.3 16km SSE of San Pedro, CA
  13. 2.1 1km SSE of Long Beach, CA
  14. 1.6 0km N of Carson, CA
  15. 1.7 6km W of Marina del Rey, 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 2021-09-18 — it released about 1,700 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.