Earthquake · reviewed by a seismologist
M 1.5md
5km NNE of Fremont, CA
- When
- Magnitude
- M 1.5 (md)
- Depth
- 8.6 km below the surface
- Felt
- no reports yet
- Nearest
- Alameda County, 9 km NNE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2987 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 5.9 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 1,800,000× the energy of this one
- Around the size people start to feel M 3.0 160× the energy of this one
- This earthquake M 1.5 about 5.9 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 37.5812, -121.9622. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| Alameda County, CA | 9 km (5 mi) | SSW of here | earthquakes near Alameda County |
| Contra Costa County, CA | 38 km (23 mi) | S of here | earthquakes near Contra Costa County |
| San Mateo County, CA | 41 km (25 mi) | ENE of here | earthquakes near San Mateo County |
| Santa Clara County, CA | 47 km (29 mi) | NNW of here | earthquakes near Santa Clara County |
| Santa Cruz County, CA | 63 km (39 mi) | N of here | earthquakes near Santa Cruz County |
| San Joaquin County, CA | 72 km (45 mi) | WSW of here | earthquakes near San Joaquin County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
59 earthquakes have been recorded within 50 km since this one.
- 1.8 2km NE of San Ramon, CA
- 1.5 7km SSE of Portola Valley, CA
- 1.8 7km SSE of Portola Valley, CA
- 2.2 1km NNW of Alamo, CA
- 1.6 2km SW of Diablo, CA
- 1.9 4km S of Loyola, CA
- 1.9 10km ENE of Milpitas, CA
- 1.5 3km ESE of Berkeley, CA
- 1.7 3km NW of Diablo, CA
- 2.3 16km SSE of Livermore, CA
- 1.6 4km NNW of San Leandro, CA
- 1.8 6km ESE of San Ramon, CA
- 1.9 18km SSE of Livermore, CA
- 1.6 6km ESE of San Ramon, CA
- 1.6 9km WSW of Brentwood, 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 19,000 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.