Earthquake · reviewed by a seismologist
M 2.3md
3km W of Orinda, CA
- When
- Magnitude
- M 2.3 (md)
- Depth
- 7.0 km below the surface
- Felt
- 208 reports · strongest reported intensity III
- Nearest
- Contra Costa County, 24 km ENE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 1415 days ago
This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 208 people have reported feeling it to USGS.
How big was it?
This earthquake released about 82 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 5.8 180,000× the energy of this one
- Magna, Utah 2020 M 5.7 130,000× the energy of this one
- Around the size people start to feel M 3.0 12× the energy of this one
- This earthquake M 2.3 about 82 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.
Where
Epicentre 37.8738, -122.2177. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| Contra Costa County, CA | 24 km (15 mi) | WSW of here | earthquakes near Contra Costa County |
| Alameda County, CA | 37 km (23 mi) | NW of here | earthquakes near Alameda County |
| Solano County, CA | 50 km (31 mi) | SSW of here | earthquakes near Solano County |
| Marin County, CA | 50 km (31 mi) | ESE of here | earthquakes near Marin County |
| San Mateo County, CA | 53 km (33 mi) | NNE of here | earthquakes near San Mateo County |
| Napa County, CA | 71 km (44 mi) | S of here | earthquakes near Napa County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
53 earthquakes have been recorded within 50 km since this one.
- 1.7 1km NE of Diablo, CA
- 1.5 2km S of Dublin, CA
- 1.8 2km NNW of Oakland, CA
- 1.9 3km WNW of Concord, CA
- 1.5 2km W of Concord, CA
- 1.7 2km WNW of Concord, CA
- 2.1 2km NNE of San Leandro, CA
- 1.7 4km WNW of Dublin, CA
- 2.6 4km WSW of Colma, CA
- 1.5 7km E of Santa Venetia, CA
- 2.1 10km ESE of Fremont, CA
- 2.1 6km NW of Bay Point, CA
- 2.2 4km W of San Francisco Zoo, CA
- 1.9 2km ENE of Berkeley, CA
- 1.6 6km SSW of Suisun City, 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 4.5 on 2019-10-15 — it released about 1,800 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.