Earthquake · reviewed by a seismologist
M 4.0mw
Earthquake near Lennox, CA
No earthquake was likely felt in Lennox in the 24 hours to 4:43 am PST (12:43 UTC). The last one was M 1.6, 7 km (4 mi) N, at 5:53 pm PST on 10 November 2026, estimated intensity II (weak) in town. Every earthquake near Lennox
This page: a magnitude 4.0 earthquake was recorded in Lennox, CA, at 4:44 am PDT on 5 April 2021 (11:44 UTC), 19 km deep. 7,217 people have reported feeling it to USGS.
USGS: 2km E of Lennox, CA
11 km (7 mi) SE of Los Angeles, CA · in Inglewood, CA
- When
- 4:44 am PDT on 5 April 2021 ()
- Where
- in Lennox, CA · earthquakes near Lennox
- Magnitude
- M 4.0 (mw)
- Depth
- 19 km below the surface
- Felt
- 7,217 reports · strongest reported intensity V
- Measured shaking
- intensity IV (ShakeMap)
- USGS impact alert
- green
- Tsunami
- USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
- Nearest
- Los Angeles County, 29 km NNE
- Nearest mapped fault
- Newport-Inglewood-Rose Canyon fault, under 1 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 725 days ago
Earthquake alerts for Lennox, CA
Get a notification in this browser when USGS records an earthquake near Lennox, 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 light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.
At this magnitude and depth, people at rest would likely notice it out to about 95 km (59 mi) from the epicentre. 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: Westmont 3 km, intensity III · Inglewood 3 km, intensity III · Hawthorne 3 km, intensity III · Lawndale 6 km, intensity III · Gardena 6 km, intensity III · Willowbrook 8 km, intensity III · Florence-Graham 9 km, intensity III · Manhattan Beach 9 km, intensity III. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 15 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.0 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 11,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 500× the energy of this one
- Magna, Utah 2020 M 5.7 350× the energy of this one
- This earthquake M 4.0 about 15 tons of TNT
- Around the size people start to feel M 3.0 this one released 32× more
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 2020-09-19 — about 6.5 times the energy of this one.
Before 2016, the USGS record lists 17 earthquakes of M5 or more within 50 km; the five largest:
- 6.7 Northridge, California, earthquake · 36 km NNW of this epicentre
- 6.4 The 1933 Long Beach, California Earthquake · 46 km SE of this epicentre
- 5.9 The 1987 Whittier Narrows, California Earthquake · 27 km ENE of this epicentre
- 5.9 1km ENE of Granada Hills, California · 40 km NNW of this epicentre
- 5.8 The 1991 Sierra Madre, California Earthquake · 48 km NE 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 33.9405, -118.3333. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Los Angeles County, CA | 29 km (18 mi) | NNE | earthquakes near Los Angeles County |
| Orange County, CA | 59 km (37 mi) | ESE | earthquakes near Orange County |
| Ventura County, CA | 87 km (54 mi) | WNW | earthquakes near Ventura County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
59 earthquakes have been recorded within 50 km since this one.
- 2.2 1km N of Lennox, CA
- 1.7 1km ENE of Lennox, CA
- 1.8 3km WNW of Lennox, CA
- 2.1 0km N of Lennox, CA
- 2.3 1km N of Lennox, CA
- 1.9 6km WSW of Malibu Beach, CA
- 2.4 2km E of Commerce, CA
- 1.5 1km SE of Marina del Rey, CA
- 1.5 18km S of Malibu Beach, CA
- 1.7 16km S of Malibu Beach, CA
- 1.9 3km WNW of Lennox, CA
- 2.2 1km NNW of Lennox, CA
- 1.6 1km SE of Lennox, CA
- 2.1 1km SSW of Inglewood, CA
- 2.3 1km NE of Lennox, 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.