Earthquake · reviewed by a seismologist
M 1.9md
8km SSW of Brentwood, CA
- When
- Magnitude
- M 1.9 (md)
- Depth
- 19 km below the surface
- Felt
- 1 report · strongest reported intensity I
- Nearest
- Contra Costa County, 17 km WNW
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 1762 days ago
This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 1 person has reported feeling it to USGS.
How big was it?
This earthquake released about 22 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 680,000× the energy of this one
- Magna, Utah 2020 M 5.7 480,000× the energy of this one
- Around the size people start to feel M 3.0 43× the energy of this one
- This earthquake M 1.9 about 22 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 37.8612, -121.7687. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| Contra Costa County, CA | 17 km (11 mi) | ESE of here | earthquakes near Contra Costa County |
| Alameda County, CA | 27 km (17 mi) | NNE of here | earthquakes near Alameda County |
| San Joaquin County, CA | 44 km (28 mi) | W of here | earthquakes near San Joaquin County |
| Solano County, CA | 48 km (30 mi) | SSE of here | earthquakes near Solano County |
| Santa Clara County, CA | 71 km (44 mi) | N of here | earthquakes near Santa Clara County |
| San Mateo County, CA | 73 km (45 mi) | NE of here | earthquakes near San Mateo 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.
- 1.5 8km WSW of Brentwood, CA
- 2.3 4km SSE of Vallejo, CA
- 2.8 1km ENE of El Cerrito, CA
- 1.8 5km ESE of Blackhawk, CA
- 1.8 14km SE of Livermore, CA
- 1.6 10km NNE of Alum Rock, CA
- 1.6 5km E of Vallejo, CA
- 1.6 8km NNE of Milpitas, CA
- 1.8 19km SSE of Livermore, CA
- 2.0 1km NW of Concord, CA
- 1.6 2km NNE of Danville, CA
- 2.3 5km E of Blackhawk, CA
- 1.9 3km ESE of Pacheco, CA
- 1.7 2km SSW of Blackhawk, CA
- 1.6 2km NE of Union 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 6,700 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.