QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

3 km of Aromas, CA

· 6.5 km deep · released about 38 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Santa Cruz County 33 kmSanta Clara County 34 kmSan Benito County 61 kmMonterey County 81 kmSan Mateo County 84 kmAlameda County 85 kmMerced County 88 kmStanislaus County 92 kmContra Costa County 115 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
6.5 km below the surface
Felt
no reports yet
Nearest
Santa Cruz County, 33 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 726 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 38 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 5.8 390,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 280,000× the energy of this one
  3. Around the size people start to feel M 3.0 25× the energy of this one
  4. This earthquake M 2.1 about 38 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 36.9142, -121.6542. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Santa Cruz County, CA 33 km (21 mi) ESE of here earthquakes near Santa Cruz County
Santa Clara County, CA 34 km (21 mi) S of here earthquakes near Santa Clara County
San Benito County, CA 61 km (38 mi) NW of here earthquakes near San Benito County
Monterey County, CA 81 km (50 mi) NNW of here earthquakes near Monterey County
San Mateo County, CA 84 km (52 mi) SE of here earthquakes near San Mateo County
Alameda County, CA 85 km (53 mi) SSE of here earthquakes near Alameda County

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

Aftershocks so far

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

  1. 1.8 14 km SSW of Bonny Doon, CA
  2. 2.7 18 km NNE of Morgan Hill, CA
  3. 1.7 5 km NW of Hollister, CA
  4. 1.6 15 km NNW of Pinnacles, CA
  5. 1.7 15 km NNE of Morgan Hill, CA
  6. 1.6 17 km NW of Pinnacles, CA
  7. 1.7 4 km SSW of San Juan Bautista, CA
  8. 1.7 6 km SW of Gilroy, CA
  9. 2.2 2 km E of Aromas, CA
  10. 2.4 10 km SW of Tres Pinos, CA
  11. 2.1 3 km NNE of Corralitos, CA
  12. 1.7 2 km E of Aromas, CA
  13. 1.9 13 km NNE of Morgan Hill, CA
  14. 1.9 9 km SW of Morgan Hill, CA
  15. 1.9 16 km S 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 5.1 on 2022-10-25 — it released about 31,000 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.