QuakeIndex

Earthquake · reviewed by a seismologist

M 2.6ml

Earthquake near Westminster, CA

No earthquake was likely felt in Westminster in the 24 hours to 4:22 am PST (12:22 UTC). The last one was M 3.2, 17 km (10 mi) W, at 12:44 am PDT on 9 October 2026, estimated intensity II (weak) in town; 1,090 felt reports to USGS. Every earthquake near Westminster

This page: a magnitude 2.6 earthquake was recorded 4 km (3 mi) south-southwest of Westminster, CA, at 11:19 pm PDT on 21 August 2020 (06:19 UTC), 15 km deep. 641 people have reported feeling it to USGS.

USGS: 4km SSW of Westminster, CA

in Huntington Beach, CA · 48 km (30 mi) SE of Los Angeles, CA

11:19 pm PDT, Aug 21, 2020 · · 15 km deep · released about 280 lb of TNT

10 km30 km60 km120 km N Orange County 24 kmLos Angeles County 57 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
11:19 pm PDT on 21 August 2020 ()
Where
4 km (3 mi) south-southwest of Westminster, CA · earthquakes near Westminster
Magnitude
M 2.6 (ml)
Depth
15 km below the surface
Felt
641 reports · strongest reported intensity IV
Nearest
Orange County, 24 km ESE
Nearest mapped fault
Newport-Inglewood-Rose Canyon fault, 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 1055 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 20 km (12 mi) from the epicentre. In Westminster, 4 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: Westminster 4 km, intensity II · Seal Beach 7 km, intensity II · Fountain Valley 7 km, intensity II · Huntington Beach 8 km, intensity II · Stanton 9 km, intensity II · Garden Grove 10 km, intensity II · Cypress 10 km, intensity II · Costa Mesa 14 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 280 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 55,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 39,000× the energy of this one
  3. Around the size people start to feel M 3.0 3.5× the energy of this one
  4. This earthquake M 2.6 about 280 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 11 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 The 1933 Long Beach, California Earthquake · 11 km SSE of this epicentre
  2. 5.9 The 1987 Whittier Narrows, California Earthquake · 38 km N of this epicentre
  3. 5.4 5km S of Chino Hills, CA · 35 km NE of this epicentre
  4. 5.3 7km W of Newport Beach, CA · 12 km SSE of this epicentre
  5. 5.2 8km ENE of Trabuco Canyon, CA · 48 km E 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 33.7253, -118.0303. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 24 km (15 mi) ESE earthquakes near Orange County
Los Angeles County, CA 57 km (35 mi) NNW earthquakes near Los Angeles County
Ventura County, CA 124 km (77 mi) NW earthquakes near Ventura County
San Diego County, CA 140 km (87 mi) ESE earthquakes near San Diego County

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

Aftershocks so far

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

  1. 1.9 10km WSW of Rancho Palos Verdes, CA
  2. 1.5 2km E of La Habra, CA
  3. 1.6 2km ESE of Compton, CA
  4. 1.9 4km W of El Segundo, CA
  5. 2.0 4km NNE of Walnut, CA
  6. 2.6 6km NW of Corona, CA
  7. 1.6 6km NW of Corona, CA
  8. 1.9 6km NW of Corona, CA
  9. 1.9 4km SSW of San Dimas, CA
  10. 1.5 1km NNW of La Habra, CA
  11. 2.4 5km WSW of Hermosa Beach, CA
  12. 2.3 3km S of Yorba Linda, CA
  13. 1.6 4km W of South El Monte, CA
  14. 1.6 3km NNW of Brea, CA
  15. 1.6 9km SSE of Chino, 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.