QuakeIndex

Earthquake · reviewed by a seismologist

M 4.2mw

3 km of Aromas, CA

· 6.9 km deep · released about 25 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Santa Cruz County 33 kmSanta Clara County 35 kmSan Benito County 61 kmMonterey County 81 kmSan Mateo County 85 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 4.2 (mw)
Depth
6.9 km below the surface
Felt
4076 reports · strongest reported intensity V
Measured shaking
intensity V (ShakeMap)
USGS impact alert
green
Tsunami
USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Nearest
Santa Cruz County, 33 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 13 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 4076 people have reported feeling it to USGS.

How big was it?

This earthquake released about 25 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 6,700× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 300× the energy of this one
  3. Magna, Utah 2020 M 5.7 210× the energy of this one
  4. This earthquake M 4.2 about 25 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 53× 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.

Where

Epicentre 36.9118, -121.6533. 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 35 km (21 mi) S of here earthquakes near Santa Clara County
San Benito County, CA 61 km (38 mi) WNW 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 85 km (53 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

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

  1. 1.7 5 km NW of Hollister, CA
  2. 1.6 15 km NNW of Pinnacles, CA
  3. 1.7 15 km NNE of Morgan Hill, CA
  4. 1.6 17 km NW of Pinnacles, CA
  5. 1.7 4 km SSW of San Juan Bautista, CA
  6. 1.7 6 km SW of Gilroy, CA
  7. 2.2 2 km E of Aromas, CA
  8. 2.4 10 km SW of Tres Pinos, CA
  9. 2.1 3 km NNE of Corralitos, CA
  10. 1.7 2 km E of Aromas, CA
  11. 1.9 13 km NNE of Morgan Hill, CA
  12. 1.9 9 km SW of Morgan Hill, CA
  13. 1.9 16 km S of Tres Pinos, CA
  14. 2.8 5 km SE of Aromas, CA
  15. 1.7 13 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 23 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.