Earthquake · reviewed by a seismologist
M 2.8md
2km E of Pacheco, CA
- When
- Magnitude
- M 2.8 (md)
- Depth
- 15 km below the surface
- Felt
- 89 reports · strongest reported intensity IV
- Nearest
- Contra Costa County, 11 km SE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 3102 days ago
This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 89 people have reported feeling it to USGS.
How big was it?
This earthquake released about 460 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 33,000× the energy of this one
- Magna, Utah 2020 M 5.7 23,000× the energy of this one
- Around the size people start to feel M 3.0 2.1× the energy of this one
- This earthquake M 2.8 about 460 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 37.9803, -122.0517. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| Contra Costa County, CA | 11 km (7 mi) | NW of here | earthquakes near Contra Costa County |
| Solano County, CA | 33 km (21 mi) | SSW of here | earthquakes near Solano County |
| Alameda County, CA | 39 km (24 mi) | NNW of here | earthquakes near Alameda County |
| Marin County, CA | 61 km (38 mi) | E of here | earthquakes near Marin County |
| Napa County, CA | 63 km (39 mi) | SSE of here | earthquakes near Napa County |
| San Joaquin County, CA | 69 km (43 mi) | W of here | earthquakes near San Joaquin County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
56 earthquakes have been recorded within 50 km since this one.
- 1.6 3km W of Concord, CA
- 1.7 2km E of Danville, CA
- 2.4 2km E of Danville, CA
- 1.7 2km ESE of Danville, CA
- 2.8 2km ESE of Danville, CA
- 1.9 3km NE of Orinda, CA
- 1.9 3km NE of Orinda, CA
- 3.0 2km ESE of Pacheco, CA
- 1.8 3km W of Orinda, CA
- 1.8 3km NW of Diablo, CA
- 1.7 2km NW of Diablo, CA
- 1.8 3km NW of Diablo, CA
- 1.5 3km NW of Diablo, CA
- 2.7 3km NW of Diablo, CA
- 1.6 4km ENE of Oakland, 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 4.4 on 2018-01-04 — it released about 240 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.