Earthquake · reviewed by a seismologist
M 1.6ml
Earthquake near Norco, CA
No earthquake was likely felt in Norco in the 24 hours to 5:02 am PST (13:02 UTC). The last one was M 1.8, 11 km (7 mi) SSE, at 11:31 am PST on 5 November 2026, estimated intensity II (weak) in town. Every earthquake near Norco
This page: a magnitude 1.6 earthquake was recorded 4 km (2 mi) north of Norco, CA, at 10:35 pm PDT on 26 April 2020 (05:35 UTC), 4.8 km deep. 7 people have reported feeling it to USGS.
USGS: 4km N of Norco, CA
in Eastvale, CA · 79 km (49 mi) E of Los Angeles, CA
- When
- 10:35 pm PDT on 26 April 2020 ()
- Where
- 4 km (2 mi) north of Norco, CA · earthquakes near Norco
- Magnitude
- M 1.6 (ml)
- Depth
- 4.8 km below the surface
- Felt
- 7 reports · strongest reported intensity II
- Nearest
- Orange County, 38 km SSW
- Nearest mapped fault
- Elsinore fault, 14 km from its surface trace — near is not the same as on
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2389 days ago
Earthquake alerts for Norco, CA
Get a notification in this browser when USGS records an earthquake near Norco, CA. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
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 10 km (6 mi) from the epicentre. In Norco, 4 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: Eastvale in town, intensity II · Norco 4 km, intensity II · Pedley 7 km, intensity II · Corona 10 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 7.3 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 2,100,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,500,000× the energy of this one
- Around the size people start to feel M 3.0 130× the energy of this one
- This earthquake M 1.6 about 7.3 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 15,000 times the energy of this one.
Before 2016, the USGS record lists 12 earthquakes of M5 or more within 50 km; the five largest:
- 6.2 3 km SE of San Bernardino, California · 30 km ENE of this epicentre
- 6.0 The 1910 Lake Elsinore, California Earthquake · 33 km SSE of this epicentre
- 5.9 The 1987 Whittier Narrows, California Earthquake · 50 km WNW of this epicentre
- 5.5 The 1990 Upland, California Earthquake · 24 km NNW of this epicentre
- 5.4 5km S of Chino Hills, CA · 20 km W of this epicentre
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 33.9648, -117.5525. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Orange County, CA | 38 km (24 mi) | SSW | earthquakes near Orange County |
| Los Angeles County, CA | 70 km (44 mi) | WNW | earthquakes near Los Angeles County |
| San Diego County, CA | 127 km (79 mi) | SE | earthquakes near San Diego County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
55 earthquakes have been recorded within 50 km since this one.
- 1.6 5km SSE of Home Gardens, CA
- 2.8 6km SSE of Pedley, CA
- 1.8 5km NNW of Fontana, CA
- 1.5 5km SSE of Home Gardens, CA
- 1.6 7 km SSE of Home Gardens, CA
- 1.8 12km NE of Trabuco Canyon, CA
- 1.6 1km E of Redlands, CA
- 1.8 10km ENE of Trabuco Canyon, CA
- 1.8 0km ESE of Lakeland Village, CA
- 2.0 3km ENE of Colton, CA
- 2.0 4 km SE of Home Gardens, CA
- 1.8 3 km ENE of Colton, CA
- 1.5 2 km SSW of Brea, CA
- 1.5 2km ESE of Home Gardens, CA
- 1.5 7km SSW of Lytle Creek, CA
Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . 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.