Earthquake · reviewed by a seismologist
M 1.6ml
Earthquake near Willowbrook, CA
No earthquake was likely felt in Willowbrook in the 24 hours to 1:37 pm PST (21:37 UTC). The last one was M 1.8, 4 km (2 mi) SW, at 2:31 pm PDT on 31 October 2026, estimated intensity II (weak) in town. Every earthquake near Willowbrook
This page: a magnitude 1.6 earthquake was recorded 2 km (1 mi) north-northwest of Willowbrook, CA, at 1:02 am PST on 20 December 2018 (09:02 UTC), 9.8 km deep.
USGS: 2km NNW of Willowbrook, CA
16 km (10 mi) SE of Los Angeles, CA · 6 km (4 mi) NW of Compton, CA
- When
- 1:02 am PST on 20 December 2018 ()
- Where
- 2 km (1 mi) north-northwest of Willowbrook, CA · earthquakes near Willowbrook
- Magnitude
- M 1.6 (ml)
- Depth
- 9.8 km below the surface
- Felt
- no reports yet
- Nearest
- Los Angeles County, 29 km N
- Nearest mapped fault
- Newport-Inglewood-Rose Canyon fault, 5 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 2884 days ago
Earthquake alerts for Willowbrook, CA
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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 5 km (3 mi) from the epicentre. In Willowbrook, 2 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: Willowbrook 2 km, intensity II · Westmont 4 km, intensity II · Florence-Graham 4 km, intensity II · Lynwood 5 km, intensity II · South Gate 5 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
No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.
Before 2016, the USGS record lists 17 earthquakes of M5 or more within 50 km; the five largest:
- 6.7 Northridge, California, earthquake · 40 km NW of this epicentre
- 6.4 The 1933 Long Beach, California Earthquake · 42 km SE of this epicentre
- 5.9 The 1987 Whittier Narrows, California Earthquake · 22 km NE of this epicentre
- 5.9 1km ENE of Granada Hills, California · 43 km NNW of this epicentre
- 5.8 The 1991 Sierra Madre, California Earthquake · 45 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 33.9373, -118.2640. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Los Angeles County, CA | 29 km (18 mi) | N | earthquakes near Los Angeles County |
| Orange County, CA | 54 km (33 mi) | ESE | earthquakes near Orange County |
| Ventura County, CA | 93 km (58 mi) | WNW | earthquakes near Ventura County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
54 earthquakes have been recorded within 50 km since this one.
- 1.9 16km S of San Pedro, CA
- 1.7 8km NNE of Malibu, CA
- 1.8 3km NNW of Orange, CA
- 2.0 3km ESE of Northridge, CA
- 2.7 3km ESE of Northridge, CA
- 1.7 4km SE of San Fernando, CA
- 1.9 9km SW of Newport Beach, CA
- 1.6 2km W of Bell Gardens, CA
- 1.5 6km N of Pacoima, CA
- 1.7 1km NNE of Inglewood, CA
- 1.9 2km NNW of Inglewood, CA
- 2.0 7km ESE of San Pedro, CA
- 2.4 6km WSW of Hermosa Beach, CA
- 1.6 3km SW of Orange, CA
- 2.8 2km ESE of Pacoima, 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.