QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

1km SW of Norwalk, CA

· 11 km deep · released about 15 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Los Angeles County 36 kmOrange County 38 kmVentura County 109 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
11 km below the surface
Felt
no reports yet
Nearest
Los Angeles County, 36 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2692 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 15 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 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× the energy of this one
  4. This earthquake M 1.8 about 15 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 33.9008, -118.0903. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Los Angeles County, CA 36 km (23 mi) SSE of here earthquakes near Los Angeles County
Orange County, CA 38 km (24 mi) NW of here earthquakes near Orange County
Ventura County, CA 109 km (68 mi) ESE of here earthquakes near Ventura County

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

Aftershocks so far

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

  1. 1.7 22km SSW of Seal Beach, CA
  2. 1.7 11km W of Palos Verdes Estates, CA
  3. 3.5 23km SSW of Seal Beach, CA
  4. 1.6 6km SE of Ontario, CA
  5. 1.6 10km NE of North Tustin, CA
  6. 1.7 4km WNW of Huntington Beach, CA
  7. 1.9 21km S of Rancho Palos Verdes, CA
  8. 1.5 5km SSW of Baldwin Hills, CA
  9. 2.0 7km E of Topanga, CA
  10. 1.8 21km SSW of San Pedro, CA
  11. 2.0 0km WNW of Manhattan Beach, CA
  12. 1.8 0km W of Manhattan Beach, CA
  13. 1.7 21km SSW of Seal Beach, CA
  14. 1.9 6km WNW of Mira Loma, CA
  15. 1.7 5km ENE of San Joaquin Hills, 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 4.4 on 2018-08-29 — it released about 7,400 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.