Earthquake · reviewed by a seismologist
M 2.5md
Earthquake near San Jose, CA
No earthquake was likely felt in San Jose in the 24 hours to 4:42 am PST (12:42 UTC). The last one was M 2.6, 19 km (12 mi) E, at 12:38 pm PDT on 27 October 2026, estimated intensity II (weak) in town; 8 felt reports to USGS. Every earthquake near San Jose
This page: a magnitude 2.5 earthquake was recorded 44 km (28 mi) east-northeast of San Jose, CA, at 1:22 am PST on 4 January 2018 (09:22 UTC), 2.5 km deep. 22 people have reported feeling it to USGS.
USGS: 22km W of Westley, CA
41 km (25 mi) NE of San Jose, CA · 24 km (15 mi) S of Tracy, CA
- When
- 1:22 am PST on 4 January 2018 ()
- Where
- 44 km (28 mi) east-northeast of San Jose, CA · earthquakes near San Jose
- Magnitude
- M 2.5 (md)
- Depth
- 2.5 km below the surface
- Felt
- 22 reports · strongest reported intensity III
- Nearest
- Santa Clara County, 39 km SW
- Nearest mapped fault
- Greenville fault, 9 km from its surface trace — near is not the same as on
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 3213 days ago
Earthquake alerts for San Jose, CA
Get a notification in this browser when USGS records an earthquake near San Jose, CA. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.
At this magnitude and depth, people at rest would likely notice it out to about 22 km (14 mi) from the epicentre. In San Jose, 44 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.
Earthquakes near other towns within 30 km: Tracy, Patterson.
How big was it?
This earthquake released about 190 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 78,000× the energy of this one
- Magna, Utah 2020 M 5.7 55,000× the energy of this one
- Around the size people start to feel M 3.0 4.9× the energy of this one
- This earthquake M 2.5 about 190 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.
For this area
The largest earthquake within 50 km since 2016 was M 4.1 on 2017-10-10 — about 210 times the energy of this one.
Before 2016, the USGS record lists 11 earthquakes of M5 or more within 50 km; the five largest:
- 6.5 Near Morgan Hill, California · 48 km SSW of this epicentre
- 6.2 Near San Jose, California · 39 km SW of this epicentre
- 6.2 The 1984 Morgan Hill, California Earthquake · 31 km SW of this epicentre
- 6.1 Near San Jose, California · 47 km SW of this epicentre
- 5.8 The 1979 Coyote Lake, California Earthquake · 46 km S of this epicentre
Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.
Where
Epicentre 37.5108, -121.4422. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Santa Clara County, CA | 39 km (24 mi) | SW | earthquakes near Santa Clara County |
| Stanislaus County, CA | 39 km (24 mi) | E | earthquakes near Stanislaus County |
| Alameda County, CA | 44 km (27 mi) | WNW | earthquakes near Alameda County |
| San Joaquin County, CA | 49 km (31 mi) | NNE | earthquakes near San Joaquin County |
| Contra Costa County, CA | 64 km (40 mi) | NW | earthquakes near Contra Costa County |
| Merced County, CA | 73 km (45 mi) | ESE | earthquakes near Merced County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
13 earthquakes have been recorded within 50 km since this one.
- 1.7 6km E of Fremont, CA
- 1.8 9km ENE of Milpitas, CA
- 1.8 6km W of French Camp, CA
- 1.8 9km E of Livermore, CA
- 2.0 12km SSW of Mountain House, CA
- 2.5 8km ENE of San Martin, CA
- 2.9 16km E of Seven Trees, CA
- 1.6 10km NNE of Alum Rock, CA
- 2.0 15km E of Seven Trees, CA
- 3.0 16km N of Morgan Hill, CA
- 1.5 7km SE of Seven Trees, CA
- 1.5 9km SE of Livermore, CA
- 2.0 20km W 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.
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.