QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5md

1 km SW of Aptos Hills-Larkin Valley, CA

· 5.2 km deep · released about 170 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Santa Cruz County 16 kmSanta Clara County 33 kmSan Mateo County 70 kmAlameda County 77 kmSan Benito County 77 kmMonterey County 92 kmStanislaus County 100 kmMerced County 103 kmContra Costa County 108 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 2.5 (md)
Depth
5.2 km below the surface
Felt
122 reports · strongest reported intensity III
Nearest
Santa Cruz County, 16 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 128 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 122 people have reported feeling it to USGS.

How big was it?

This earthquake released about 170 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.

  1. Mineral, Virginia 2011 M 5.8 89,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 63,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.6× the energy of this one
  4. This earthquake M 2.5 about 170 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 36.9547, -121.8403. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Santa Cruz County, CA 16 km (10 mi) ESE of here earthquakes near Santa Cruz County
Santa Clara County, CA 33 km (20 mi) SSW of here earthquakes near Santa Clara County
San Mateo County, CA 70 km (43 mi) SE of here earthquakes near San Mateo County
Alameda County, CA 77 km (48 mi) S of here earthquakes near Alameda County
San Benito County, CA 77 km (48 mi) WNW of here earthquakes near San Benito County
Monterey County, CA 92 km (57 mi) NNW of here earthquakes near Monterey County

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

Aftershocks so far

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

  1. 2.0 6 km SE of Lexington Hills, CA
  2. 1.6 3 km S of Ridgemark, CA
  3. 1.6 8 km ENE of Hollister, CA
  4. 1.8 11 km N of Hollister, CA
  5. 2.3 5 km W of San Juan Bautista, CA
  6. 1.7 2 km ENE of Aromas, CA
  7. 1.8 8 km ENE of Gilroy, CA
  8. 1.5 2 km ENE of Ridgemark, CA
  9. 3.6 2 km ENE of Ridgemark, CA
  10. 1.6 5 km SW of Ridgemark, CA
  11. 1.9 1 km SSE of Ridgemark, CA
  12. 1.6 12 km NNW of Boulder Creek, CA
  13. 2.8 14 km N of Morgan Hill, CA
  14. 2.6 16 km E of Seven Trees, CA
  15. 1.6 2 km ESE of Aromas, 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 6,900 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.