Earthquake · reviewed by a seismologist
M 2.7md
6km SSW of San Ramon, CA
- When
- Magnitude
- M 2.7 (md)
- Depth
- 7.8 km below the surface
- Felt
- 117 reports · strongest reported intensity III
- Nearest
- Alameda County, 12 km SE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 1775 days ago
This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 117 people have reported feeling it to USGS.
How big was it?
This earthquake released about 350 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.7 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 43,000× the energy of this one
- Magna, Utah 2020 M 5.7 31,000× the energy of this one
- Around the size people start to feel M 3.0 2.7× the energy of this one
- This earthquake M 2.7 about 350 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 37.7307, -121.9923. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| Alameda County, CA | 12 km (7 mi) | NW of here | earthquakes near Alameda County |
| Contra Costa County, CA | 21 km (13 mi) | S of here | earthquakes near Contra Costa County |
| San Mateo County, CA | 48 km (30 mi) | NE of here | earthquakes near San Mateo County |
| Solano County, CA | 60 km (37 mi) | S of here | earthquakes near Solano County |
| Santa Clara County, CA | 63 km (39 mi) | NNW of here | earthquakes near Santa Clara County |
| San Joaquin County, CA | 67 km (42 mi) | WSW 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
52 earthquakes have been recorded within 50 km since this one.
- 1.5 3km NNW of Union City, CA
- 1.6 5km NW of Dublin, CA
- 2.4 9km ESE of Fremont, CA
- 1.5 6km WNW of Dublin, CA
- 3.1 6km WNW of Dublin, CA
- 1.5 5km E of Vallejo, CA
- 2.3 8km ESE of Fremont, CA
- 2.9 10km NE of Milpitas, CA
- 2.2 5km E of Vallejo, CA
- 1.8 1km NW of Diablo, CA
- 1.7 3km ESE of Pacheco, CA
- 1.7 6km WNW of Dublin, CA
- 1.6 5km E of Vallejo, CA
- 1.9 10km NE of Milpitas, CA
- 1.7 5km NW of Dublin, 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 420 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.