QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

Earthquake near Glendora, CA

No earthquake was likely felt in Glendora in the 24 hours to 5:56 am PST (13:56 UTC). The last one was M 3.6, 64 km (40 mi) WSW, at 8:40 am PDT on 27 September 2026, estimated intensity II (weak) in town; 1,735 felt reports to USGS. Every earthquake near Glendora

This page: a magnitude 1.8 earthquake was recorded in Glendora, CA, at 4:29 am PDT on 10 August 2022 (11:29 UTC), 15 km deep.

USGS: 2km WNW of Glendora, CA

in Glendora, CA · 50 km (31 mi) ENE of Los Angeles, CA

4:29 am PDT, Aug 10, 2022 · · 15 km deep · released about 13 lb of TNT

10 km30 km60 km120 km N Los Angeles County 35 kmOrange County 53 kmVentura County 117 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
4:29 am PDT on 10 August 2022 ()
Where
in Glendora, CA · earthquakes near Glendora
Magnitude
M 1.8 (ml)
Depth
15 km below the surface
Felt
no reports yet
Nearest
Los Angeles County, 35 km W
Nearest mapped fault
Sierra Madre 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 1555 days ago

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

At this magnitude and depth it was probably too small to be felt, even directly above it. 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: Azusa, Citrus, Charter Oak, Covina, Irwindale, Bradbury.

How big was it?

This earthquake released about 13 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 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 810,000× the energy of this one
  3. Around the size people start to feel M 3.0 72× the energy of this one
  4. This earthquake M 1.8 about 13 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 15,000 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. 5.9 The 1987 Whittier Narrows, California Earthquake · 20 km WSW of this epicentre
  2. 5.8 The 1991 Sierra Madre, California Earthquake · 17 km NW of this epicentre
  3. 5.5 The 1990 Upland, California Earthquake · 17 km E of this epicentre
  4. 5.4 5km S of Chino Hills, CA · 24 km SSE of this epicentre
  5. 5.2 3km W of Lytle Creek, CA · 35 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 34.1405, -117.8853. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Los Angeles County, CA 35 km (22 mi) W earthquakes near Los Angeles County
Orange County, CA 53 km (33 mi) S earthquakes near Orange County
Ventura County, CA 117 km (73 mi) WNW earthquakes near Ventura County

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

Aftershocks so far

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

  1. 1.5 5km SSE of Home Gardens, CA
  2. 2.4 1km WNW of Muscoy, CA
  3. 1.9 3km N of Carson, CA
  4. 1.9 5km SE of Ontario, CA
  5. 1.9 5km NW of Mira Loma, CA
  6. 1.7 8km N of Rancho Cucamonga, CA
  7. 2.2 3km SW of Pedley, CA
  8. 2.5 0km SSW of View Park-Windsor Hills, CA
  9. 2.8 5km ESE of Yorba Linda, CA
  10. 1.5 6km SSW of Chino Hills, CA
  11. 1.5 3km SSE of Duarte, CA
  12. 1.6 1km ESE of View Park-Windsor Hills, CA
  13. 1.9 5km ESE of Lytle Creek, CA
  14. 2.7 0km E of Carson, CA
  15. 1.8 4km SE of Home Gardens, 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.