Earthquake · reviewed by a seismologist
M 3.5ml
27 km WSW of Westley, CA
- When
- Magnitude
- M 3.5 (ml)
- Depth
- 2.4 km below the surface
- Felt
- 8 reports · strongest reported intensity II
- Measured shaking
- intensity IV (ShakeMap)
- Nearest
- Santa Clara County, 30 km SW
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 3 hours ago
This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 8 people have reported feeling it to USGS.
How big was it?
This earthquake released about 2.3 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.5 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 75,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 3,300× the energy of this one
- Magna, Utah 2020 M 5.7 2,400× the energy of this one
- This earthquake M 3.5 about 2.3 tons of TNT
- Around the size people start to feel M 3.0 this one released 4.7× more
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.
Revisions
USGS refines a solution as more stations report. Every change we have seen is listed here.
| What changed | From | To | When |
|---|---|---|---|
| felt reports | 7 | 8 | |
| felt reports | 5 | 7 | |
| reported intensity | 2.2 | 2.4 | |
| felt reports | 3 | 5 | |
| measured intensity | 3.62 | 3.61 | |
| reported intensity | not reported | 2.2 | |
| felt reports | not reported | 3 | |
| review status | automatic | reviewed | |
| measured intensity | not reported | 3.62 |
Where
Epicentre 37.4177, -121.4555. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| Santa Clara County, CA | 30 km (19 mi) | NE of here | earthquakes near Santa Clara County |
| Stanislaus County, CA | 43 km (27 mi) | WSW of here | earthquakes near Stanislaus County |
| Alameda County, CA | 48 km (30 mi) | ESE of here | earthquakes near Alameda County |
| San Joaquin County, CA | 60 km (37 mi) | SSW of here | earthquakes near San Joaquin County |
| Santa Cruz County, CA | 67 km (41 mi) | NE of here | earthquakes near Santa Cruz County |
| Merced County, CA | 69 km (43 mi) | WNW of here | earthquakes near Merced County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
4 earthquakes have been recorded within 50 km since this one.
- 1.7 26 km WSW of Westley, CA
- 1.4 26 km WSW of Westley, CA
- 2.6 26 km WSW of Westley, CA
- 1.3 26 km WSW of Westley, 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 5.1 on 2022-10-25 — it released about 260 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.