Earthquake · reviewed by a seismologist
M 2.4md
53km WNW of Petrolia, CA
Yes. A magnitude 2.4 earthquake was recorded 53km WNW of Petrolia, CA, at 2:18 am PST on 3 March 2021 (10:18 UTC), 17 km deep.
- When
- Magnitude
- M 2.4 (md)
- Depth
- 17 km below the surface
- Felt
- no reports yet
- Nearest
- Humboldt County, 86 km ENE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2079 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 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 14 km (9 mi) from the epicentre. 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 140 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 110,000× the energy of this one
- Magna, Utah 2020 M 5.7 78,000× the energy of this one
- Around the size people start to feel M 3.0 6.9× the energy of this one
- This earthquake M 2.4 about 140 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 99,000 times the energy of this one.
Before 2016, the USGS record lists 29 earthquakes of M5 or more within 50 km; the five largest:
- 6.6 32 km SW of Ferndale, California · 29 km ESE of this epicentre
- 6.5 30 km WSW of Ferndale, California · 28 km E of this epicentre
- 6.5 The 2010 Eureka, California Earthquake · 28 km NE of this epicentre
- 6.0 53 km SW of Ferndale, California · 28 km SSE of this epicentre
- 6.0 near the coast of Northern California · 33 km NNE 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 40.4450, -124.8907. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Humboldt County, CA | 86 km (54 mi) | ENE | earthquakes near Humboldt 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.
- 1.8 16km W of Petrolia, CA
- 1.6 14km WSW of Petrolia, CA
- 2.2 23km W of Petrolia, CA
- 2.4 12km W of Petrolia, CA
- 2.5 15km WSW of Petrolia, CA
- 2.8 13km W of Petrolia, CA
- 2.8 49km W of Ferndale, CA
- 2.7 13km NW of Petrolia, CA
- 2.4 23km W of Petrolia, CA
- 2.5 10km NNW of Petrolia, CA
- 1.8 13km W of Petrolia, CA
- 1.7 14km WSW of Petrolia, CA
- 2.5 31km WNW of Petrolia, CA
- 2.8 35km WNW of Petrolia, CA
- 1.8 18km WNW of Ferndale, 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.