Earthquake · reviewed by a seismologist
M 2.3md
Earthquake near Ferndale, CA
No earthquake was likely felt in Ferndale in the 24 hours to 5:25 am PST (13:25 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 2.3 earthquake was recorded 50 km (31 mi) southwest of Ferndale, CA, at 8:47 pm PDT on 14 October 2020 (03:47 UTC), 18 km deep.
USGS: 39km W of Petrolia, CA
- When
- 8:47 pm PDT on 14 October 2020 ()
- Where
- 50 km (31 mi) southwest of Ferndale, CA · earthquakes near Ferndale
- Magnitude
- M 2.3 (md)
- Depth
- 18 km below the surface
- Felt
- no reports yet
- Nearest
- Humboldt County, 82 km ENE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2211 days ago
Earthquake alerts for Ferndale, 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 9 km (6 mi) from the epicentre. In Ferndale, 50 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 88 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 170,000× the energy of this one
- Magna, Utah 2020 M 5.7 120,000× the energy of this one
- Around the size people start to feel M 3.0 11× the energy of this one
- This earthquake M 2.3 about 88 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 150,000 times the energy of this one.
Before 2016, the USGS record lists 41 earthquakes of M5 or more within 50 km; the five largest:
- 7.2 The 1992 Petrolia, California Earthquake · 44 km E of this epicentre
- 6.6 32 km SW of Ferndale, California · 18 km ENE of this epicentre
- 6.5 30 km WSW of Ferndale, California · 20 km NE of this epicentre
- 6.5 The 2010 Eureka, California Earthquake · 37 km N of this epicentre
- 6.0 Offshore Humboldt County, California · 42 km SSW 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 40.3250, -124.7500. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Humboldt County, CA | 82 km (51 mi) | ENE | earthquakes near Humboldt County |
| Mendocino County, CA | 149 km (93 mi) | SE | earthquakes near Mendocino County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
58 earthquakes have been recorded within 50 km since this one.
- 2.5 18km WNW of Petrolia, CA
- 2.8 24km W of Petrolia, CA
- 2.2 8km WSW of Petrolia, CA
- 4.4 80km W of Petrolia, CA
- 1.8 19km W of Petrolia, CA
- 2.4 16km SW of Ferndale, CA
- 2.6 9km WSW of Petrolia, CA
- 2.7 18km WSW of Petrolia, CA
- 3.0 86km W of Petrolia, CA
- 4.3 77km W of Petrolia, CA
- 3.2 12km WSW of Petrolia, CA
- 2.9 7km WNW of Petrolia, CA
- 2.8 13km W of Petrolia, CA
- 2.6 27km W of Petrolia, CA
- 2.3 12km WSW of Rio Dell, 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.