Earthquake near San Bernardino, CA

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 2 km (1 mi) from the epicentre. In San Bernardino, 3 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: San Bernardino 3 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 43 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 350,000× the energy of this one
2. Magna, Utah 2020 M 5.7 250,000× the energy of this one
3. Around the size people start to feel M 3.0 22× the energy of this one
4. This earthquake M 2.1 about 43 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 2016-01-06 — about 2,700 times the energy of this one.

Before 2016, the USGS record lists 20 earthquakes of M5 or more within 50 km; the five largest:

1. 6.3 The 1992 Big Bear, California Earthquake · 46 km ENE of this epicentre Jun 28, 1992
2. 6.2 3 km SE of San Bernardino, California · 6 km ESE of this epicentre Jul 23, 1923
3. 6.0 The 1910 Lake Elsinore, California Earthquake · 46 km S of this epicentre May 15, 1910
4. 5.6 7km ENE of Running Springs, CA · 29 km ENE of this epicentre Oct 16, 1999
5. 5.5 The 1990 Upland, California Earthquake · 35 km W of this epicentre Feb 28, 1990

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 34.1102, -117.3183. Map © OpenStreetMap contributors.

Nearby places

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

Aftershocks so far

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

1. 2.5 9km N of Rancho Cucamonga, CA 05:18 UTC
2. 2.6 4km NW of Fontana, CA 16:19 UTC
3. 1.9 10km S of Big Bear City, CA 03:57 UTC
4. 1.8 11km NNE of Banning, CA 03:10 UTC
5. 2.4 3km ENE of Lytle Creek, CA 12:16 UTC
6. 1.8 8km NNW of Fontana, CA 09:36 UTC
7. 1.7 6km E of Calimesa, CA 08:37 UTC
8. 1.6 2km W of Devore, CA 14:37 UTC
9. 1.7 8km SSE of Redlands, CA 22:12 UTC
10. 1.8 5km WNW of Beaumont, CA 20:47 UTC
11. 1.6 4km N of Fontana, CA 17:47 UTC
12. 2.5 4km SSE of Charter Oak, CA 13:59 UTC
13. 2.9 2km N of Yucaipa, CA 19:16 UTC
14. 2.2 5km ENE of Calimesa, CA 02:28 UTC
15. 1.9 4km SE of Home Gardens, CA 20:00 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 22:11 UTC. 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.