QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

Earthquake near Norwalk, CA

No earthquake was likely felt in Norwalk in the 24 hours to 3:21 am PST (11:21 UTC). The last one was M 3.2, 16 km (10 mi) SW, at 12:44 am PDT on 9 October 2026, estimated intensity III (weak) in town; 1,090 felt reports to USGS. Every earthquake near Norwalk

This page: a magnitude 3.1 earthquake was recorded in Norwalk, CA, at 1:51 am PST on 26 February 2019 (09:51 UTC), 12 km deep. 1,449 people have reported feeling it to USGS.

USGS: 2km SSW of Norwalk, CA

in Norwalk, CA · 33 km (20 mi) ESE of Los Angeles, CA

1:51 am PST, Feb 26, 2019 · · 12 km deep · released about 1,500 lb of TNT

Every earthquake near Norwalk Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Los Angeles County 37 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
1:51 am PST on 26 February 2019 ()
Where
in Norwalk, CA · earthquakes near Norwalk
Magnitude
M 3.1 (ml)
Depth
12 km below the surface
Felt
1,449 reports · strongest reported intensity V
Measured shaking
intensity V (ShakeMap)
Nearest
Los Angeles County, 37 km NNW
Nearest mapped fault
Puente Hills blind thrust system, 2 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 1845 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 42 km (26 mi) from the epicentre. 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: Norwalk in town, intensity III · Bellflower 3 km, intensity III · Cerritos 4 km, intensity III · Lakewood 6 km, intensity III · Paramount 7 km, intensity III · Downey 7 km, intensity III · La Mirada 8 km, intensity III · South Whittier 8 km, intensity III. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1,500 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 220,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 9,800× the energy of this one
  3. Magna, Utah 2020 M 5.7 6,900× the energy of this one
  4. This earthquake M 3.1 about 1,500 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.6× 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.

For this area

The largest earthquake within 50 km since 2016 was M 4.4 on 2018-08-29 — about 72 times the energy of this one.

Before 2016, the USGS record lists 13 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 The 1933 Long Beach, California Earthquake · 30 km SSE of this epicentre
  2. 5.9 The 1987 Whittier Narrows, California Earthquake · 19 km N of this epicentre
  3. 5.8 The 1991 Sierra Madre, California Earthquake · 43 km NNE of this epicentre
  4. 5.5 The 1990 Upland, California Earthquake · 46 km NE of this epicentre
  5. 5.4 5km S of Chino Hills, CA · 30 km ENE 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 33.8930, -118.0883. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Los Angeles County, CA 37 km (23 mi) NNW earthquakes near Los Angeles County
Orange County, CA 38 km (23 mi) SE earthquakes near Orange County
Ventura County, CA 109 km (68 mi) WNW earthquakes near Ventura County

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

Aftershocks so far

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

  1. 2.0 4km W of East Los Angeles, CA
  2. 2.6 2km NNE of Gardena, CA
  3. 2.5 13km S of Rancho Palos Verdes, CA
  4. 1.9 1km N of Caltech, Pasadena, CA
  5. 1.9 2km SSE of View Park-Windsor Hills, CA
  6. 1.5 0km NNW of Paramount, CA
  7. 2.6 6km ENE of North Tustin, CA
  8. 1.9 1km N of Huntington Park, CA
  9. 1.8 1km SW of Norwalk, CA
  10. 1.6 6km ENE of North Tustin, CA
  11. 1.8 1km ENE of Gardena, CA
  12. 2.1 4km ENE of Brea, CA
  13. 1.8 6km WSW of Huntington Beach, CA
  14. 1.6 4km E of Newport Beach, CA
  15. 1.6 2km NNW of Valinda, 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.