Earthquake · reviewed by a seismologist
M 2.1md
7km NE of San Martin, CA
- When
- Magnitude
- M 2.1 (md)
- Depth
- 5.2 km below the surface
- Felt
- no reports yet
- Nearest
- Santa Clara County, 17 km NW
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 1781 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 49 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 310,000× the energy of this one
- Magna, Utah 2020 M 5.7 220,000× the energy of this one
- Around the size people start to feel M 3.0 19× the energy of this one
- This earthquake M 2.1 about 49 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 37.1228, -121.5492. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| Santa Clara County, CA | 17 km (10 mi) | SE of here | earthquakes near Santa Clara County |
| Santa Cruz County, CA | 43 km (26 mi) | ENE of here | earthquakes near Santa Cruz County |
| Alameda County, CA | 67 km (41 mi) | SSE of here | earthquakes near Alameda County |
| Stanislaus County, CA | 69 km (43 mi) | SW of here | earthquakes near Stanislaus County |
| San Benito County, CA | 70 km (44 mi) | NW of here | earthquakes near San Benito County |
| Merced County, CA | 74 km (46 mi) | W of here | earthquakes near Merced County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
37 earthquakes have been recorded within 50 km since this one.
- 1.6 7km SW of Ridgemark, CA
- 1.6 5km SSW of Tres Pinos, CA
- 2.0 2km SSE of Tres Pinos, CA
- 1.7 7km ENE of Gilroy, CA
- 2.3 9km E of Gilroy, CA
- 1.9 9km E of Gilroy, CA
- 1.7 27km NE of Hollister, CA
- 1.7 11km NE of Milpitas, CA
- 1.5 10km ENE of Milpitas, CA
- 2.1 9km E of Alum Rock, CA
- 2.1 9km SSW of Tres Pinos, CA
- 2.0 5km ESE of Aromas, CA
- 2.1 26km SW of Gustine, CA
- 1.8 5km NNE of Alum Rock, CA
- 1.9 1km E of Hollister, 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 4.2 on 2021-01-17 — it released about 1,200 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.