Earthquake · reviewed by a seismologist
M 1.5md
6km NW of Pacifica, CA
- When
- Magnitude
- M 1.5 (md)
- Depth
- 6.9 km below the surface
- Felt
- no reports yet
- Nearest
- San Mateo County, 30 km SSE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2195 days ago
This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.
How big was it?
This earthquake released about 6.2 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 2,500,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,700,000× the energy of this one
- Around the size people start to feel M 3.0 150× the energy of this one
- This earthquake M 1.5 about 6.2 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 37.6590, -122.5257. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| San Mateo County, CA | 30 km (19 mi) | NNW of here | earthquakes near San Mateo County |
| San Francisco County, CA | 45 km (28 mi) | E of here | earthquakes near San Francisco County |
| Marin County, CA | 48 km (30 mi) | SSE of here | earthquakes near Marin County |
| Alameda County, CA | 54 km (34 mi) | W of here | earthquakes near Alameda County |
| Contra Costa County, CA | 58 km (36 mi) | WSW of here | earthquakes near Contra Costa County |
| Solano County, CA | 85 km (53 mi) | SW of here | earthquakes near Solano County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
40 earthquakes have been recorded within 50 km since this one.
- 1.6 6km ESE of Fairview, CA
- 1.8 2km ESE of Berkeley, CA
- 2.6 1km ENE of Union City, CA
- 1.5 3km ESE of Berkeley, CA
- 2.6 3km ESE of Berkeley, CA
- 2.1 2km WNW of Castro Valley, CA
- 1.9 2km NW of Orinda, CA
- 1.7 9km NW of San Francisco Zoo, CA
- 2.0 5km SW of Danville, CA
- 1.9 3km S of Los Altos Hills, CA
- 2.0 6km WNW of San Francisco Zoo, CA
- 1.8 7km NW of San Francisco Zoo, CA
- 2.3 7km NW of San Francisco Zoo, CA
- 2.2 2km S of Los Altos Hills, CA
- 1.7 3km S of Los Altos Hills, 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 18,000 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.