Earthquake · reviewed by a seismologist
M 1.9md
3km NW of Castro Valley, CA
- When
- Magnitude
- M 1.9 (md)
- Depth
- 5.3 km below the surface
- Felt
- 9 reports · strongest reported intensity II
- Nearest
- Alameda County, 19 km ESE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2409 days ago
This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 9 people have reported feeling it to USGS.
How big was it?
This earthquake released about 18 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 5.8 840,000× the energy of this one
- Magna, Utah 2020 M 5.7 600,000× the energy of this one
- Around the size people start to feel M 3.0 53× the energy of this one
- This earthquake M 1.9 about 18 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 37.7147, -122.1103. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| Alameda County, CA | 19 km (12 mi) | WNW of here | earthquakes near Alameda County |
| Contra Costa County, CA | 27 km (17 mi) | SSW of here | earthquakes near Contra Costa County |
| San Mateo County, CA | 41 km (25 mi) | NE of here | earthquakes near San Mateo County |
| Solano County, CA | 63 km (39 mi) | SSW of here | earthquakes near Solano County |
| Santa Clara County, CA | 66 km (41 mi) | NW of here | earthquakes near Santa Clara County |
| Marin County, CA | 67 km (42 mi) | ESE of here | earthquakes near Marin County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
55 earthquakes have been recorded within 50 km since this one.
- 1.5 8km WSW of Mountain House, CA
- 2.1 8km WSW of Mountain House, CA
- 1.9 8km SW of Brentwood, CA
- 1.6 5km W of San Francisco Zoo, CA
- 1.6 5km W of San Francisco Zoo, CA
- 2.0 9km WSW of Mountain House, CA
- 2.0 7km SE of Blackhawk, CA
- 1.8 8km ESE of Blackhawk, CA
- 1.7 10km SW of Brentwood, CA
- 1.7 9km WSW of Mountain House, CA
- 1.7 4km NW of Orinda, CA
- 1.5 4km NNE of Fairview, CA
- 1.5 2km E of Berkeley, CA
- 1.5 19km SSE of Livermore, CA
- 1.6 2km S of Pittsburg, 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 8,200 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.