Earthquake near Rowland Heights, CA

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. In Rowland Heights, 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.

Earthquakes near other towns within 30 km: Brea, South San Jose Hills, La Habra Heights, Walnut, La Habra, Hacienda Heights.

How big was it?

This earthquake released about 14 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
2. Magna, Utah 2020 M 5.7 760,000× the energy of this one
3. Around the size people start to feel M 3.0 68× the energy of this one
4. This earthquake M 1.8 about 14 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 2018-08-29 — about 7,900 times the energy of this one.

Before 2016, the USGS record lists 14 earthquakes of M5 or more within 50 km; the five largest:

1. 6.4 The 1933 Long Beach, California Earthquake · 38 km SSW of this epicentre Mar 11, 1933
2. 5.9 The 1987 Whittier Narrows, California Earthquake · 22 km WNW of this epicentre Oct 1, 1987
3. 5.8 The 1991 Sierra Madre, California Earthquake · 36 km NNW of this epicentre Jun 28, 1991
4. 5.5 The 1990 Upland, California Earthquake · 26 km NE of this epicentre Feb 28, 1990
5. 5.4 5km S of Chino Hills, CA · 10 km E of this epicentre Jul 29, 2008

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 33.9595, -117.8765. 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. 1.6 7km SSE of Home Gardens, CA 17:00 UTC
2. 2.0 3km NNW of Fontana, CA 06:27 UTC
3. 1.5 3km SE of Home Gardens, CA 19:30 UTC
4. 2.1 12km SSE of San Pedro, CA 14:17 UTC
5. 1.5 5km S of Lytle Creek, CA 23:12 UTC
6. 1.8 5km S of Lytle Creek, CA 23:00 UTC
7. 1.5 5km NE of Bradbury, CA 13:23 UTC
8. 1.5 9km NE of Trabuco Canyon, CA 02:58 UTC
9. 2.0 4km SE of Home Gardens, CA 19:29 UTC
10. 1.7 3km ESE of Home Gardens, CA 22:01 UTC
11. 1.5 0km ESE of Redondo Beach, CA 21:27 UTC
12. 2.1 1km S of View Park-Windsor Hills, CA 00:17 UTC
13. 1.6 3km SE of Home Gardens, CA 19:32 UTC
14. 1.6 4km N of Norco, CA 05:35 UTC
15. 1.5 3km W of Highland Park, CA 09:24 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 11:53 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.