Earthquake · reviewed by a seismologist
M 1.9md
19km SW of Bolinas, CA
- When
- Magnitude
- M 1.9 (md)
- Depth
- 7.0 km below the surface
- Felt
- no reports yet
- Nearest
- San Francisco County, 18 km WSW
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 3209 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 20 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 5.8 760,000× the energy of this one
- Magna, Utah 2020 M 5.7 540,000× the energy of this one
- Around the size people start to feel M 3.0 48× the energy of this one
- This earthquake M 1.9 about 20 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 37.7985, -122.8483. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| San Francisco County, CA | 18 km (11 mi) | ENE of here | earthquakes near San Francisco County |
| Marin County, CA | 30 km (18 mi) | SSW of here | earthquakes near Marin County |
| San Mateo County, CA | 60 km (37 mi) | NW of here | earthquakes near San Mateo County |
| Contra Costa County, CA | 80 km (50 mi) | W of here | earthquakes near Contra Costa County |
| Sonoma County, CA | 81 km (50 mi) | S of here | earthquakes near Sonoma County |
| Alameda County, CA | 84 km (52 mi) | WNW of here | earthquakes near Alameda 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.
- 1.7 7km NNE of Inverness, CA
- 1.7 3km WSW of San Francisco Zoo, CA
- 1.9 39km SSW of Point Reyes, CA
- 2.4 33km S of Point Reyes, CA
- 1.6 8km WNW of San Francisco Zoo, CA
- 1.8 7km SSW of Muir Beach, CA
- 2.2 3km NNW of Pacifica, CA
- 1.8 6km WSW of Colma, CA
- 1.9 6km WSW of Colma, CA
- 1.6 6km WSW of Colma, CA
- 3.5 5km WSW of Colma, CA
- 1.8 1km E of El Cerrito, CA
- 2.6 6km WSW of San Francisco Zoo, CA
- 2.5 6km WSW of San Francisco Zoo, CA
- 1.5 0km SE 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.