QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9ml

Earthquake near Long Beach, CA

No earthquake was likely felt in Long Beach in the 24 hours to 4:51 am PST (12:51 UTC). The last one was M 1.7, 10 km (6 mi) SSW, at 3:16 am PDT on 16 October 2026, estimated intensity II (weak) in town. Every earthquake near Long Beach

This page: a magnitude 1.9 earthquake was recorded 7 km (5 mi) south-southwest of Long Beach, CA, at 2:57 pm PDT on 24 September 2021 (21:57 UTC), 8.9 km deep.

USGS: 7km ESE of San Pedro, CA

10 km (6 mi) SSW of Long Beach, CA · 39 km (24 mi) SSE of Los Angeles, CA

2:57 pm PDT, Sep 24, 2021 · · 8.9 km deep · released about 24 lb of TNT

Every earthquake near Long Beach Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 42 kmLos Angeles County 55 kmVentura County 111 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
2:57 pm PDT on 24 September 2021 ()
Where
7 km (5 mi) south-southwest of Long Beach, CA · earthquakes near Long Beach
Magnitude
M 1.9 (ml)
Depth
8.9 km below the surface
Felt
no reports yet
Nearest
Orange County, 42 km E
Nearest mapped fault
Palos Verdes fault, under 1 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1875 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 12 km (7 mi) from the epicentre. In Long Beach, 7 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Likely felt in: Long Beach 7 km, intensity II · Seal Beach 12 km, intensity II · Signal Hill 12 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 24 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 640,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 450,000× the energy of this one
  3. Around the size people start to feel M 3.0 40× the energy of this one
  4. This earthquake M 1.9 about 24 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.

For this area

The largest earthquake within 50 km since 2016 was M 4.5 on 2020-09-19 — about 8,200 times the energy of this one.

Before 2016, the USGS record lists 10 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 The 1933 Long Beach, California Earthquake · 23 km ESE of this epicentre
  2. 5.9 The 1987 Whittier Narrows, California Earthquake · 42 km NNE of this epicentre
  3. 5.3 2 km SSW of Santa Monica, California · 41 km NW of this epicentre
  4. 5.3 7km W of Newport Beach, CA · 23 km ESE of this epicentre
  5. 5.2 13km S of Malibu Beach, CA · 49 km WNW of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 33.7070, -118.2262. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 42 km (26 mi) E earthquakes near Orange County
Los Angeles County, CA 55 km (34 mi) N earthquakes near Los Angeles County
Ventura County, CA 111 km (69 mi) NW earthquakes near Ventura County

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

Aftershocks so far

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

  1. 1.6 2km NW of Marina del Rey, CA
  2. 2.1 1km WSW of View Park-Windsor Hills, CA
  3. 3.3 1km SE of South Gate, CA
  4. 1.6 3km ENE of La Mirada, CA
  5. 1.9 23km WSW of Dana Point, CA
  6. 1.5 1km E of View Park-Windsor Hills, CA
  7. 1.6 2km W of Inglewood, CA
  8. 1.6 1km ENE of Carson, CA
  9. 2.0 22km SW of Huntington Beach, CA
  10. 2.3 3km ESE of Carson, CA
  11. 1.5 2km ESE of Carson, CA
  12. 2.2 11km S of Malibu Beach, CA
  13. 1.9 3km ESE of Carson, CA
  14. 2.5 3km SE of Carson, CA
  15. 1.5 2km SE of Carson, 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.