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 22 km (14 mi) from the epicentre. In San Bernardino, 8 km away, the estimate is intensity III (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: Highland 7 km, intensity III · San Bernardino 8 km, intensity III · Muscoy 8 km, intensity III · Lake Arrowhead 10 km, intensity II · Colton 12 km, intensity II · Rialto 13 km, intensity II · Loma Linda 14 km, intensity II · Redlands 15 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 160 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 95,000× the energy of this one
2. Magna, Utah 2020 M 5.7 68,000× the energy of this one
3. Around the size people start to feel M 3.0 6× the energy of this one
4. This earthquake M 2.5 about 160 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 2018-05-08 — about 1,000 times the energy of this one.

Before 2016, the USGS record lists 15 earthquakes of M5 or more within 50 km; the five largest:

1. 6.3 The 1992 Big Bear, California Earthquake · 40 km E of this epicentre Jun 28, 1992
2. 6.2 3 km SE of San Bernardino, California · 10 km S of this epicentre Jul 23, 1923
3. 5.6 7km ENE of Running Springs, CA · 21 km ENE of this epicentre Oct 16, 1999
4. 5.5 The 1990 Upland, California Earthquake · 40 km W of this epicentre Feb 28, 1990
5. 5.5 11km SSE of Big Bear Lake, California · 38 km E of this epicentre Jun 28, 1992

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 34.1753, -117.2600. Map © OpenStreetMap contributors.

Nearby places

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

Aftershocks so far

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

1. 1.7 4km WNW of Banning, CA 15:36 UTC
2. 1.7 3km NNW of Mira Loma, CA 04:18 UTC
3. 1.9 9km NNE of Banning, CA 03:15 UTC
4. 1.7 5km SSW of Devore, CA 06:42 UTC
5. 1.5 6km N of Moreno Valley, CA 12:18 UTC
6. 2.2 6km SSE of Mentone, CA 18:13 UTC
7. 1.5 6km NNW of Glen Avon, CA 10:10 UTC
8. 2.0 8km S of Big Bear Lake, CA 07:10 UTC
9. 2.0 4km SSW of Lytle Creek, CA 08:57 UTC
10. 2.0 8km NNE of Banning, CA 13:12 UTC
11. 1.9 1km E of Redlands, CA 04:51 UTC
12. 2.4 3km S of Loma Linda, CA 04:27 UTC
13. 1.7 1km ENE of Redlands, CA 15:11 UTC
14. 2.0 5km S of Redlands, CA 01:32 UTC
15. 1.6 9km N of Big Bear City, CA 17:48 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 22:16 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.