QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4md

13km WSW of Santa Cruz, CA

· 8.1 km deep · released about 140 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Santa Cruz County 17 kmSanta Clara County 54 kmSan Mateo County 59 kmAlameda County 85 kmSan Benito County 101 kmMonterey County 106 kmContra Costa County 113 kmSan Francisco County 119 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 2.4 (md)
Depth
8.1 km below the surface
Felt
59 reports · strongest reported intensity III
Nearest
Santa Cruz County, 17 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1431 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 59 people have reported feeling it to USGS.

How big was it?

This earthquake released about 140 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 110,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 78,000× the energy of this one
  3. Around the size people start to feel M 3.0 6.9× the energy of this one
  4. This earthquake M 2.4 about 140 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 36.9132, -122.1602. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Santa Cruz County, CA 17 km (11 mi) SW of here earthquakes near Santa Cruz County
Santa Clara County, CA 54 km (34 mi) SW of here earthquakes near Santa Clara County
San Mateo County, CA 59 km (37 mi) SSE of here earthquakes near San Mateo County
Alameda County, CA 85 km (53 mi) SSW of here earthquakes near Alameda County
San Benito County, CA 101 km (63 mi) WNW of here earthquakes near San Benito County
Monterey County, CA 106 km (66 mi) NW of here earthquakes near Monterey County

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

Aftershocks so far

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

  1. 1.5 6km NNW of Aromas, CA
  2. 2.4 7km WSW of Gilroy, CA
  3. 1.9 6km SSE of Portola Valley, CA
  4. 1.5 6km SW of Gilroy, CA
  5. 2.2 5km S of Loyola, CA
  6. 2.0 8km W of Saratoga, CA
  7. 1.8 4km SSW of Cupertino, CA
  8. 1.7 2km E of Aromas, CA
  9. 1.7 7km WSW of Gilroy, CA
  10. 1.8 2km E of Aromas, CA
  11. 1.6 5km WSW of Cupertino, CA
  12. 1.8 3km WSW of Cupertino, CA
  13. 1.7 2km ENE of Aromas, CA
  14. 1.7 3km SSE of Aptos Hills-Larkin Valley, CA
  15. 2.1 10km SW of Bonny Doon, 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 2021-01-17 — it released about 440 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.