QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

6km WSW of Gilroy, CA

· 3.9 km deep · released about 51 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Santa Clara County 28 kmSanta Cruz County 34 kmSan Benito County 63 kmAlameda County 79 kmSan Mateo County 82 kmMerced County 84 kmStanislaus County 85 kmMonterey County 86 kmContra Costa County 109 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
Magnitude
M 2.1 (md)
Depth
3.9 km below the surface
Felt
5 reports · strongest reported intensity II
Nearest
Santa Clara County, 28 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3102 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 5 people have reported feeling it to USGS.

How big was it?

This earthquake released about 51 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.

  1. Mineral, Virginia 2011 M 5.8 300,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 210,000× the energy of this one
  3. Around the size people start to feel M 3.0 19× the energy of this one
  4. This earthquake M 2.1 about 51 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 36.9765, -121.6240. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Santa Clara County, CA 28 km (17 mi) SSE of here earthquakes near Santa Clara County
Santa Cruz County, CA 34 km (21 mi) E of here earthquakes near Santa Cruz County
San Benito County, CA 63 km (39 mi) NW of here earthquakes near San Benito County
Alameda County, CA 79 km (49 mi) SSE of here earthquakes near Alameda County
San Mateo County, CA 82 km (51 mi) SE of here earthquakes near San Mateo County
Merced County, CA 84 km (52 mi) WSW of here earthquakes near Merced County

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

Aftershocks so far

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

  1. 1.6 15km SSE of Tres Pinos, CA
  2. 1.9 14km SSE of Tres Pinos, CA
  3. 2.0 8km NE of Ridgemark, CA
  4. 1.8 13km N of Morgan Hill, CA
  5. 1.5 14km SSE of Tres Pinos, CA
  6. 1.6 15km SSE of Tres Pinos, CA
  7. 1.8 15km N of Morgan Hill, CA
  8. 2.2 15km SSE of Tres Pinos, CA
  9. 1.7 24km WSW of Los Banos, CA
  10. 1.7 9km ENE of San Martin, CA
  11. 1.6 3km ENE of Aromas, CA
  12. 1.5 16km SSE of Tres Pinos, CA
  13. 1.7 16km NW of Pinnacles, CA
  14. 2.9 17km SSE of Tres Pinos, CA
  15. 2.8 16km SSE of Tres Pinos, 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 2016-07-19 — it released about 1,300 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

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