Earthquake · reviewed by a seismologist
M 4.4mw
5km NNE of Petrolia, CA
- When
- Magnitude
- M 4.4 (mw)
- Depth
- 30 km below the surface
- Felt
- 114 reports · strongest reported intensity V
- Measured shaking
- intensity IV (ShakeMap)
- USGS impact alert
- green
- Tsunami
- USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
- Nearest
- Humboldt County, 47 km NE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 1717 days ago
This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 114 people have reported feeling it to USGS.
How big was it?
This earthquake released about 56 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.4 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 3,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 130× the energy of this one
- Magna, Utah 2020 M 5.7 95× the energy of this one
- This earthquake M 4.4 about 56 tons of TNT
- Around the size people start to feel M 3.0 this one released 120× 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.
Where
Epicentre 40.3630, -124.2553. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| Humboldt County, CA | 47 km (29 mi) | SW of here | earthquakes near Humboldt County |
| Trinity County, CA | 102 km (63 mi) | WSW of here | earthquakes near Trinity County |
| Mendocino County, CA | 125 km (77 mi) | NNW of here | earthquakes near Mendocino County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
59 earthquakes have been recorded within 50 km since this one.
- 1.8 6km NE of Petrolia, CA
- 2.5 18km W of Petrolia, CA
- 2.6 11km WSW of Rio Dell, CA
- 2.6 5km NNW of Petrolia, CA
- 2.8 10km SSE of Ferndale, CA
- 1.9 15km NNW of Petrolia, CA
- 2.8 12km NNW of Petrolia, CA
- 2.9 9km N of Petrolia, CA
- 1.8 6km NNW of Petrolia, CA
- 2.3 12km SW of Rio Dell, CA
- 2.7 11km N of Petrolia, CA
- 2.6 9km S of Ferndale, CA
- 2.7 9km SW of Petrolia, CA
- 2.6 8km N of Petrolia, CA
- 2.5 10km ESE 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.
For this area
The largest earthquake within 50 km in our catalogue was M 5.6 on 2019-06-23 — it released about 63 times the energy of this one.
From the QuakeIndex catalogue, built from the USGS FDSN event service.
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.