5 km NNW of Corona, CA

2026-09-21 23:05 UTC · 3.3 km deep · released about 0.29 lb of TNT

Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.

When: 2026-09-21 23:05 UTC
Magnitude: M 0.7 (ml)
Depth: 3.3 km below the surface
Felt: no reports yet
Nearest: Orange County, 31 km SW
Status: Reviewed by a seismologist

USGS · last changed by USGS 6 days ago · we first saw it 7 hours ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 0.29 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 1.7 would have released about 32 times as much.

Mineral, Virginia 2011 M 5.8 51,000,000× the energy of this one
Magna, Utah 2020 M 5.7 36,000,000× the energy of this one
Around the size people start to feel M 3.0 3,200× the energy of this one
This earthquake M 0.7 about 0.29 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.

Where

Map loads when it scrolls into view

Epicentre 33.9068, -117.5887. Map © OpenStreetMap contributors.

Nearby places

Place	Distance	Direction
Orange County, CA	31 km (19 mi)	NE of here	earthquakes near Orange County
Los Angeles County, CA	70 km (43 mi)	ESE of here	earthquakes near Los Angeles County
San Diego County, CA	124 km (77 mi)	NW of here	earthquakes near San Diego County

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

Aftershocks so far

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

1.5 9 km ESE of Yorba Linda, CA 11:56 UTC
1.1 4 km NNW of Mira Loma, CA 17:29 UTC
1.0 6 km WNW of Calimesa, CA 12:20 UTC
1.3 8 km S of Chino Hills, CA 12:03 UTC
1.3 3 km ENE of Fontana, CA 05:46 UTC
0.8 9 km WSW of Beaumont, CA 04:38 UTC
1.0 9 km E of Yorba Linda, CA 00:25 UTC
0.7 8 km NNE of Moreno Valley, CA 21:51 UTC
1.3 3 km SE of Home Gardens, CA 19:17 UTC
1.5 10 km ENE of North Tustin, CA 17:54 UTC
0.7 6 km S of Redlands, CA 11:40 UTC
0.9 6 km S of Redlands, CA 11:38 UTC
0.9 1 km ESE of Home Gardens, CA 20:04 UTC
1.4 5 km NNW of Lake Elsinore, CA 18:53 UTC
1.1 6 km S of Redlands, CA 17:30 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 12:09 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

For this area

The largest earthquake within 50 km in our catalogue was M 4.5 on 2020-09-19 — it released about 660,000 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

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.