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 15 km (9 mi) from the epicentre. In San Bernardino, 2 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 2 km, intensity II · Colton 4 km, intensity II · Rialto 5 km, intensity II · Muscoy 6 km, intensity II · Loma Linda 8 km, intensity II · Highland 10 km, intensity II · Fontana 11 km, intensity II · Redlands 14 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 100 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 140,000× the energy of this one
2. Magna, Utah 2020 M 5.7 100,000× the energy of this one
3. Around the size people start to feel M 3.0 9.1× the energy of this one
4. This earthquake M 2.4 about 100 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 1,100 times the energy of this one.

Before 2016, the USGS record lists 21 earthquakes of M5 or more within 50 km; the five largest:

1. 6.7 The 1918 San Jacinto, California Earthquake · 50 km SE of this epicentre Apr 21, 1918
2. 6.3 The 1992 Big Bear, California Earthquake · 46 km ENE of this epicentre Jun 28, 1992
3. 6.2 3 km SE of San Bernardino, California · 6 km ESE of this epicentre Jul 23, 1923
4. 6.0 The 1910 Lake Elsinore, California Earthquake · 46 km S of this epicentre May 15, 1910
5. 5.6 7km ENE of Running Springs, CA · 29 km ENE of this epicentre Oct 16, 1999

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 34.1088, -117.3165. Map © OpenStreetMap contributors.

Nearby places

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. 1.7 6km SSW of Redlands, CA 01:04 UTC
2. 1.5 1km NE of Calimesa, CA 22:28 UTC
3. 3.3 3km S of Mentone, CA 01:47 UTC
4. 2.1 8km NNW of Cabazon, CA 20:05 UTC
5. 1.5 9km N of Big Bear City, CA 17:46 UTC
6. 1.7 4km W of Pomona, CA 15:26 UTC
7. 2.1 5km SSE of Mentone, CA 15:05 UTC
8. 2.2 10km E of Running Springs, CA 08:02 UTC
9. 1.9 3km W of Lake Elsinore, CA 02:05 UTC
10. 2.2 6km NNE of Fontana, CA 00:28 UTC
11. 1.6 3km E of Yucaipa, CA 10:54 UTC
12. 1.7 6km NNE of Fontana, CA 01:04 UTC
13. 2.3 4km N of Norco, CA 00:45 UTC
14. 1.5 10km E of Yucaipa, CA 21:29 UTC
15. 1.9 4km NNE of Moreno Valley, CA 21:54 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 06:55 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.