QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

Earthquake near San Martin, CA

Yes: an earthquake was likely felt in San Martin in the last 24 hours. M 2.6, 22 km (14 mi) S of San Martin, at 11:40 am PST on 12 November 2026 (19:40 UTC); the estimated shaking in San Martin was intensity II (weak). Every earthquake near San Martin

This page: a magnitude 1.7 earthquake was recorded 8 km (5 mi) east-northeast of San Martin, CA, at 6:58 am PDT on 17 September 2025 (13:58 UTC), 1.9 km deep.

USGS: 8 km ENE of San Martin, CA

13 km (8 mi) NNE of Gilroy, CA · 32 km (20 mi) SE of San Jose, CA

6:58 am PDT, Sep 17, 2025 · · 1.9 km deep · released about 12 lb of TNT

Every earthquake near San Martin Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Santa Clara County 18 kmSanta Cruz County 44 kmAlameda County 68 kmStanislaus County 68 kmSan Benito County 69 kmMerced County 72 kmSan Mateo County 81 kmSan Joaquin County 94 kmContra Costa County 96 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
6:58 am PDT on 17 September 2025 ()
Where
8 km (5 mi) east-northeast of San Martin, CA · earthquakes near San Martin
Magnitude
M 1.7 (md)
Depth
1.9 km below the surface
Felt
no reports yet
Nearest
Santa Clara County, 18 km NW
Nearest mapped fault
Calaveras fault, 1 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 414 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 13 km (8 mi) from the epicentre. In San Martin, 8 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.

Likely felt in: Morgan Hill 11 km, intensity II · Gilroy 13 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 12 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 870,000× the energy of this one
  3. Around the size people start to feel M 3.0 78× the energy of this one
  4. This earthquake M 1.7 about 12 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 5.1 on 2022-10-25 — about 95,000 times the energy of this one.

Before 2016, the USGS record lists 28 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.9 The 1989 Loma Prieta, California Earthquake · 32 km WSW of this epicentre
  2. 6.5 Near Morgan Hill, California · 9 km W of this epicentre
  3. 6.2 Near San Jose, California · 31 km NW of this epicentre
  4. 6.2 The 1984 Morgan Hill, California Earthquake · 25 km NNW of this epicentre
  5. 6.1 Near San Jose, California · 25 km WNW 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 37.1173, -121.5345. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Santa Clara County, CA 18 km (11 mi) NW earthquakes near Santa Clara County
Santa Cruz County, CA 44 km (27 mi) WSW earthquakes near Santa Cruz County
Alameda County, CA 68 km (42 mi) NNW earthquakes near Alameda County
Stanislaus County, CA 68 km (42 mi) NE earthquakes near Stanislaus County
San Benito County, CA 69 km (43 mi) SE earthquakes near San Benito County
Merced County, CA 72 km (45 mi) E earthquakes near Merced County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

54 earthquakes have been recorded within 50 km since this one.

  1. 4.0 5 km S of San Juan Bautista, CA
  2. 3.7 6 km S of San Juan Bautista, CA
  3. 2.7 6 km S of San Juan Bautista, CA
  4. 1.6 8 km E of Gilroy, CA
  5. 1.6 9 km E of Gilroy, CA
  6. 1.8 8 km E of Gilroy, CA
  7. 3.6 9 km E of Gilroy, CA
  8. 2.7 9 km E of Gilroy, CA
  9. 4.0 8 km E of Gilroy, CA
  10. 2.1 6 km N of Corralitos, CA
  11. 1.7 6 km NNE of Corralitos, CA
  12. 1.6 7 km NE of Ridgemark, CA
  13. 1.6 16 km N of Morgan Hill, CA
  14. 1.8 16 km N of Morgan Hill, CA
  15. 2.0 8 km E of Gilroy, 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

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.