Earthquake · reviewed by a seismologist
M 1.6ml
Earthquake near San Dimas, CA
No earthquake was likely felt in San Dimas in the 24 hours to 5:03 am PST (13:03 UTC). The last one was M 3.2, 23 km (14 mi) ESE, at 5:37 am PDT on 2 September 2026, estimated intensity II (weak) in town; 730 felt reports to USGS. Every earthquake near San Dimas
This page: a magnitude 1.6 earthquake was recorded in San Dimas, CA, at 3:03 pm PST on 6 January 2024 (23:03 UTC), 14 km deep. 1 person has reported feeling it to USGS.
USGS: 2 km SSW of San Dimas, CA
6 km (4 mi) NW of Pomona, CA · 56 km (35 mi) E of Los Angeles, CA
- When
- 3:03 pm PST on 6 January 2024 ()
- Where
- in San Dimas, CA · earthquakes near San Dimas
- Magnitude
- M 1.6 (ml)
- Depth
- 14 km below the surface
- Felt
- 1 report · strongest reported intensity II
- Nearest
- Los Angeles County, 43 km WNW
- Nearest mapped fault
- Sierra Madre fault, 4 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 1039 days ago
Earthquake alerts for San Dimas, CA
Get a notification in this browser when USGS records an earthquake near San Dimas, CA. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
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: Charter Oak, La Verne, Pomona, Diamond Bar, Glendora, Covina.
How big was it?
This earthquake released about 6.4 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.
- Mineral, Virginia 2011 M 5.8 2,400,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,700,000× the energy of this one
- Around the size people start to feel M 3.0 150× the energy of this one
- This earthquake M 1.6 about 6.4 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 4.5 on 2020-09-19 — about 31,000 times the energy of this one.
Before 2016, the USGS record lists 10 earthquakes of M5 or more within 50 km; the five largest:
- 5.9 The 1987 Whittier Narrows, California Earthquake · 25 km W of this epicentre
- 5.8 The 1991 Sierra Madre, California Earthquake · 26 km NW of this epicentre
- 5.5 The 1990 Upland, California Earthquake · 12 km ENE of this epicentre
- 5.4 5km S of Chino Hills, CA · 16 km SSE of this epicentre
- 5.2 3km W of Lytle Creek, CA · 32 km NE 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 34.0903, -117.8128. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Los Angeles County, CA | 43 km (27 mi) | WNW | earthquakes near Los Angeles County |
| Orange County, CA | 46 km (29 mi) | S | earthquakes near Orange County |
| San Diego County, CA | 153 km (95 mi) | SE | earthquakes near San Diego County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
56 earthquakes have been recorded within 50 km since this one.
- 1.5 9 km SW of Corona, CA
- 1.8 9 km SW of Corona, CA
- 2.2 9 km SW of Corona, CA
- 1.6 3 km WSW of Costa Mesa, CA
- 1.6 1 km WSW of Devore, CA
- 1.8 3 km N of Colton, CA
- 1.8 7 km SSE of Home Gardens, CA
- 2.6 2 km SSE of Long Beach, CA
- 2.6 2 km SE of Long Beach, CA
- 2.0 4 km SE of Home Gardens, CA
- 1.6 5 km SE of Home Gardens, CA
- 1.9 3 km N of Fontana, CA
- 2.2 3 km N of Fontana, CA
- 1.8 1 km S of La Mirada, CA
- 3.1 3 km 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.