Earthquake · reviewed by a seismologist
M 1.6ml
Earthquake near Westmorland, CA
No earthquake was likely felt in Westmorland in the 24 hours to 5:49 am PST (13:49 UTC). The last one was M 4.9, 79 km (49 mi) SSE, at 10:27 am PST on 3 November 2026, estimated intensity III (weak) in town; 321 felt reports to USGS. Every earthquake near Westmorland
This page: a magnitude 1.6 earthquake was recorded 5 km (3 mi) northeast of Westmorland, CA, at 7:26 pm PDT on 30 September 2020 (02:26 UTC), 8.1 km deep.
USGS: 5km NE of Westmorland, CA
- When
- 7:26 pm PDT on 30 September 2020 ()
- Where
- 5 km (3 mi) northeast of Westmorland, CA · earthquakes near Westmorland
- Magnitude
- M 1.6 (ml)
- Depth
- 8.1 km below the surface
- Felt
- no reports yet
- Nearest
- Imperial County, 21 km E
- Nearest mapped fault
- Brawley Seismic Zone, 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 2058 days ago
Earthquake alerts for Westmorland, CA
Get a notification in this browser when USGS records an earthquake near Westmorland, 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 7 km (4 mi) from the epicentre. In Westmorland, 5 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: Calipatria, Brawley, Niland, Imperial.
How big was it?
This earthquake released about 7.1 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 7.1 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 4.9 on 2020-10-01 — about 110,000 times the energy of this one.
Before 2016, the USGS record lists 36 earthquakes of M5 or more within 50 km; the five largest:
- 6.9 The 1940 Imperial Valley, California Earthquake · 31 km SE of this epicentre
- 6.6 The 1942 Fish Creek Mountains, California Earthquake · 22 km WSW of this epicentre
- 6.6 The 1987 Superstition Hills, California Earthquake · 26 km WSW of this epicentre
- 6.4 The 1979 Imperial Valley Earthquake, California-Baja California · 49 km SSE of this epicentre
- 6.3 The 1906 Imperial Valley, California Earthquake · 20 km SSE 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 33.0683, -115.5815. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Imperial County, CA | 21 km (13 mi) | E | earthquakes near Imperial County |
| Riverside County, CA | 83 km (52 mi) | NNW | earthquakes near Riverside County |
| San Diego County, CA | 111 km (69 mi) | W | earthquakes near San Diego County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
60 earthquakes have been recorded within 50 km since this one.
- 1.6 5km NE of Westmorland, CA
- 2.5 3km NE of Westmorland, CA
- 2.5 4km NE of Westmorland, CA
- 2.1 5km NE of Westmorland, CA
- 3.4 4km NNE of Westmorland, CA
- 2.5 5km NNE of Westmorland, CA
- 3.5 6km NNE of Westmorland, CA
- 1.7 4km E of Westmorland, CA
- 1.8 5km NNE of Westmorland, CA
- 1.8 3km E of Westmorland, CA
- 1.6 5km NE of Westmorland, CA
- 1.7 3km E of Westmorland, CA
- 1.5 5km NNE of Westmorland, CA
- 1.6 4km NNE of Westmorland, CA
- 2.1 5km NNE of Westmorland, 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.