Earthquake · reviewed by a seismologist
M 2.6md
Earthquake near Ferndale, CA
No earthquake was likely felt in Ferndale in the 24 hours to 6:38 am PST (14:38 UTC). The last one was M 5.0, 113 km (70 mi) W, at 8:56 pm PST on 4 November 2026, estimated intensity III (weak) in town; 145 felt reports to USGS. Every earthquake near Ferndale
This page: a magnitude 2.6 earthquake was recorded 43 km (27 mi) west-southwest of Ferndale, CA, at 9:44 pm PDT on 20 June 2020 (04:44 UTC), 21 km deep.
USGS: 37km WNW of Petrolia, CA
- When
- 9:44 pm PDT on 20 June 2020 ()
- Where
- 43 km (27 mi) west-southwest of Ferndale, CA · earthquakes near Ferndale
- Magnitude
- M 2.6 (md)
- Depth
- 21 km below the surface
- Felt
- no reports yet
- Nearest
- Humboldt County, 75 km ENE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2267 days ago
Earthquake alerts for Ferndale, CA
Get a notification in this browser when USGS records an earthquake near Ferndale, 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 9 km (6 mi) from the epicentre. In Ferndale, 43 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.
How big was it?
This earthquake released about 220 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 70,000× the energy of this one
- Magna, Utah 2020 M 5.7 50,000× the energy of this one
- Around the size people start to feel M 3.0 4.4× the energy of this one
- This earthquake M 2.6 about 220 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 5.8 on 2020-03-09 — about 63,000 times the energy of this one.
Before 2016, the USGS record lists 40 earthquakes of M5 or more within 50 km; the five largest:
- 7.2 The 1992 Petrolia, California Earthquake · 42 km E of this epicentre
- 6.6 32 km SW of Ferndale, California · 14 km E of this epicentre
- 6.5 30 km WSW of Ferndale, California · 13 km ENE of this epicentre
- 6.5 The 2010 Eureka, California Earthquake · 28 km N of this epicentre
- 6.0 Near Rio Dell, California · 45 km ENE 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 40.4012, -124.7148. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Humboldt County, CA | 75 km (46 mi) | ENE | earthquakes near Humboldt County |
| Mendocino County, CA | 153 km (95 mi) | SE | earthquakes near Mendocino 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.
- 2.5 14km WSW of Petrolia, CA
- 2.1 25km W of Petrolia, CA
- 2.3 11km SSW of Ferndale, CA
- 2.0 12km WNW of Petrolia, CA
- 1.7 20km WSW of Ferndale, CA
- 2.9 68km WNW of Ferndale, CA
- 2.3 14km WSW of Petrolia, CA
- 2.0 11km SSW of Ferndale, CA
- 1.6 16km WNW of Petrolia, CA
- 2.2 21km WNW of Petrolia, CA
- 2.5 65km W of Petrolia, CA
- 2.7 20km WNW of Petrolia, CA
- 2.4 11km SSW of Ferndale, CA
- 1.9 9km W of Rio Dell, CA
- 1.6 18km NW of Petrolia, 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.