Earthquake · reviewed by a seismologist
M 4.0mw
Earthquake near Covelo, CA
No earthquake was likely felt in Covelo in the 24 hours to 3:33 am PST (11:33 UTC). The last one was M 2.2, 9 km (6 mi) N, at 3:31 pm PST on 10 November 2026, estimated intensity II (weak) in town. Every earthquake near Covelo
This page: a magnitude 4.0 earthquake was recorded 5 km (3 mi) east of Covelo, CA, at 7:03 am PDT on 20 September 2022 (14:03 UTC), 9.1 km deep. 17 people have reported feeling it to USGS.
USGS: 5km E of Covelo, CA
- When
- 7:03 am PDT on 20 September 2022 ()
- Where
- 5 km (3 mi) east of Covelo, CA · earthquakes near Covelo
- Magnitude
- M 4.0 (mw)
- Depth
- 9.1 km below the surface
- Felt
- 17 reports · strongest reported intensity III
- Measured shaking
- intensity IV (ShakeMap)
- USGS impact alert
- green
- Nearest
- Mendocino County, 46 km SSW
- Nearest mapped fault
- Bartlett Springs fault system, 2 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 1447 days ago
Earthquake alerts for Covelo, CA
Get a notification in this browser when USGS records an earthquake near Covelo, 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 small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.
At this magnitude and depth, people at rest would likely notice it out to about 93 km (58 mi) from the epicentre. In Covelo, 5 km away, the estimate is intensity IV (light). 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: Covelo 5 km, intensity IV · Laytonville 28 km, intensity III · Brooktrails 43 km, intensity III · Willits 46 km, intensity III. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 13 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 13,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 580× the energy of this one
- Magna, Utah 2020 M 5.7 410× the energy of this one
- This earthquake M 4.0 about 13 tons of TNT
- Around the size people start to feel M 3.0 this one released 28× 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 4.3 on 2017-12-14 — about 2.8 times the energy of this one.
Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:
- 5.9 9 km S of Leggett, California · 47 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 39.8005, -123.1862. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Mendocino County, CA | 46 km (29 mi) | SSW | earthquakes near Mendocino County |
| Glenn County, CA | 71 km (44 mi) | ESE | earthquakes near Glenn County |
| Lake County, CA | 86 km (53 mi) | SSE | earthquakes near Lake County |
| Tehama County, CA | 89 km (55 mi) | ENE | earthquakes near Tehama County |
| Trinity County, CA | 94 km (59 mi) | N | earthquakes near Trinity County |
| Colusa County, CA | 107 km (66 mi) | SE | earthquakes near Colusa 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.
- 1.7 16km NNE of Brooktrails, CA
- 2.2 13km WSW of Laytonville, CA
- 1.8 12km WNW of Lake Pillsbury, CA
- 2.5 6km ENE of Covelo, CA
- 2.3 6km ENE of Covelo, CA
- 1.6 16km ENE of Brooktrails, CA
- 1.6 6km N of Lake Pillsbury, CA
- 1.5 11km NNE of Brooktrails, CA
- 1.7 18km NW of Lake Pillsbury, CA
- 2.2 16km WNW of Lake Pillsbury, CA
- 2.3 16km N of Lake Pillsbury, CA
- 1.8 8km WSW of Alder Springs, CA
- 1.8 36km NE of Covelo, CA
- 1.7 18km NW of Lake Pillsbury, CA
- 1.5 15km WNW of Lake Pillsbury, 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.