Earthquake · reviewed by a seismologist
M 1.6md
15km S of Half Moon Bay, CA
- When
- Magnitude
- M 1.6 (md)
- Depth
- 11 km below the surface
- Felt
- no reports yet
- Nearest
- San Mateo County, 11 km NNE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2159 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 7.6 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 2,000,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,400,000× the energy of this one
- Around the size people start to feel M 3.0 130× the energy of this one
- This earthquake M 1.6 about 7.6 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 37.3272, -122.4242. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| San Mateo County, CA | 11 km (7 mi) | SSW of here | earthquakes near San Mateo County |
| Santa Cruz County, CA | 51 km (32 mi) | NW of here | earthquakes near Santa Cruz County |
| Alameda County, CA | 57 km (36 mi) | SW of here | earthquakes near Alameda County |
| Santa Clara County, CA | 66 km (41 mi) | W of here | earthquakes near Santa Clara County |
| San Francisco County, CA | 70 km (43 mi) | SE of here | earthquakes near San Francisco County |
| Contra Costa County, CA | 78 km (48 mi) | SSW of here | earthquakes near Contra Costa County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
32 earthquakes have been recorded within 50 km since this one.
- 2.4 5km SE of Portola Valley, CA
- 2.2 2km E of Saratoga, CA
- 1.9 4km SSW of Colma, CA
- 1.8 8km SW of Loyola, CA
- 1.7 9km N of Boulder Creek, CA
- 3.9 3km N of San Lorenzo, CA
- 2.0 3km NE of Portola Valley, CA
- 2.6 2km ENE of Hayward, CA
- 1.5 6km WSW of Daly City, CA
- 1.6 11km WSW of Saratoga, CA
- 1.6 7km SW of Los Altos Hills, CA
- 2.2 4km WSW of Daly City, CA
- 1.7 11km W of Bonny Doon, CA
- 1.5 5km WSW of Lexington Hills, CA
- 1.6 4km NNW of Pacifica, 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.
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.