QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

Earthquake near Glen Avon, CA

No earthquake was likely felt in Glen Avon in the 24 hours to 4:42 am PST (12:42 UTC). The last one was M 1.6, 9 km (6 mi) N, at 6:17 am PDT on 26 October 2026, estimated intensity II (weak) in town. Every earthquake near Glen Avon

This page: a magnitude 1.5 earthquake was recorded 5 km (3 mi) northwest of Glen Avon, CA, at 11:29 am PDT on 27 August 2020 (18:29 UTC), 6.2 km deep.

USGS: 5km NW of Glen Avon, CA

7 km (4 mi) NW of Jurupa Valley, CA · 82 km (51 mi) E of Los Angeles, CA

11:29 am PDT, Aug 27, 2020 · · 6.2 km deep · released about 5.4 lb of TNT

Every earthquake near Glen Avon Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 47 kmLos Angeles County 70 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
11:29 am PDT on 27 August 2020 ()
Where
5 km (3 mi) northwest of Glen Avon, CA · earthquakes near Glen Avon
Magnitude
M 1.5 (ml)
Depth
6.2 km below the surface
Felt
no reports yet
Nearest
Orange County, 47 km SSW
Nearest mapped fault
Red Hill-Etiwanda Avenue fault, 10 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 2170 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 8 km (5 mi) from the epicentre. In Glen Avon, 5 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.

Earthquakes near other towns within 30 km: Jurupa Valley, Pedley, Sunnyslope, Rancho Cucamonga, Fontana, Eastvale.

How big was it?

This earthquake released about 5.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,800,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 2,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 180× the energy of this one
  4. This earthquake M 1.5 about 5.4 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 4.4 on 2018-08-29 — about 21,000 times the energy of this one.

Before 2016, the USGS record lists 12 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.2 3 km SE of San Bernardino, California · 25 km E of this epicentre
  2. 6.0 The 1910 Lake Elsinore, California Earthquake · 40 km SSE of this epicentre
  3. 5.8 The 1991 Sierra Madre, California Earthquake · 50 km WNW of this epicentre
  4. 5.6 7km ENE of Running Springs, CA · 49 km ENE of this epicentre
  5. 5.5 The 1990 Upland, California Earthquake · 19 km NW 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 34.0467, -117.5238. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 47 km (29 mi) SSW earthquakes near Orange County
Los Angeles County, CA 70 km (43 mi) WNW earthquakes near Los Angeles County
San Diego County, CA 133 km (83 mi) SSE earthquakes near San Diego County

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

Aftershocks so far

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

  1. 1.6 4km SW of Redlands, CA
  2. 1.5 13km NNE of Yucaipa, CA
  3. 1.6 8km SW of Lytle Creek, CA
  4. 1.9 4km SSW of San Dimas, CA
  5. 1.9 4km SSE of Home Gardens, CA
  6. 1.5 1km NNW of La Habra, CA
  7. 2.1 2km W of Devore, CA
  8. 1.7 4km SSW of Pinon Hills, CA
  9. 2.3 3km S of Yorba Linda, CA
  10. 1.7 6km E of Calimesa, CA
  11. 1.9 5km SSW of Pinon Hills, CA
  12. 1.5 5km SE of Home Gardens, CA
  13. 1.8 5km SSE of Home Gardens, CA
  14. 1.6 1km ESE of Loma Linda, CA
  15. 1.6 11km WNW of Lake Elsinore, 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.