Earthquake · reviewed by a seismologist
M 2.2ml
Earthquake near Glendora, CA
No earthquake was likely felt in Glendora in the 24 hours to 6:37 am PST (14:37 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 2.2 earthquake was recorded 14 km (9 mi) north-northeast of Glendora, CA, at 9:35 am PST on 25 January 2021 (17:35 UTC), 13 km deep.
USGS: 14km NNE of Glendora, CA
12 km (8 mi) NNE of Glendora, CA · 62 km (39 mi) ENE of Los Angeles, CA
- When
- 9:35 am PST on 25 January 2021 ()
- Where
- 14 km (9 mi) north-northeast of Glendora, CA · earthquakes near Glendora
- Magnitude
- M 2.2 (ml)
- Depth
- 13 km below the surface
- Felt
- no reports yet
- Nearest
- Los Angeles County, 43 km W
- Nearest mapped fault
- San Gabriel 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 2117 days ago
Earthquake alerts for Glendora, CA
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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 13 km (8 mi) from the epicentre. In Glendora, 14 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: San Dimas, San Antonio Heights, Azusa, La Verne, Charter Oak, Citrus.
How big was it?
This earthquake released about 60 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.2 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 250,000× the energy of this one
- Magna, Utah 2020 M 5.7 180,000× the energy of this one
- Around the size people start to feel M 3.0 16× the energy of this one
- This earthquake M 2.2 about 60 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 3,200 times the energy of this one.
Before 2016, the USGS record lists 8 earthquakes of M5 or more within 50 km; the five largest:
- 5.9 The 1987 Whittier Narrows, California Earthquake · 33 km SW of this epicentre
- 5.8 The 1991 Sierra Madre, California Earthquake · 19 km W of this epicentre
- 5.5 The 1990 Upland, California Earthquake · 15 km SE of this epicentre
- 5.4 5km S of Chino Hills, CA · 33 km S of this epicentre
- 5.2 3km W of Lytle Creek, CA · 24 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 34.2473, -117.7933. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Los Angeles County, CA | 43 km (27 mi) | W | earthquakes near Los Angeles County |
| Orange County, CA | 64 km (40 mi) | S | earthquakes near Orange County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
28 earthquakes have been recorded within 50 km since this one.
- 2.0 3km NNW of Fontana, CA
- 1.6 1km W of Sierra Madre, CA
- 1.8 4km NNW of Wrightwood, CA
- 2.4 2km E of Commerce, CA
- 1.8 11km E of Yorba Linda, CA
- 2.0 2km N of Muscoy, CA
- 2.1 2km N of Muscoy, CA
- 3.0 1km ENE of Huntington Park, CA
- 1.5 3km NW of Fontana, CA
- 3.0 2km ESE of Ontario, CA
- 1.8 7km SW of Pearblossom, CA
- 2.0 4km NE of Yorba Linda, CA
- 1.6 2km NE of Colton, CA
- 1.7 2km NNE of Colton, CA
- 2.5 3km SW of San Bernardino, 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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.