QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4md

12 km WNW of Bonny Doon, CA

· 12 km deep · released about 120 lb of TNT

10 km30 km60 km120 km N Santa Cruz County 25 kmSan Mateo County 38 kmSanta Clara County 54 kmAlameda County 70 kmContra Costa County 97 kmSan Francisco County 98 kmMarin County 116 kmSan Benito County 118 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
12 km below the surface
Felt
14 reports · strongest reported intensity III
Nearest
Santa Cruz County, 25 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 103 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 14 people have reported feeling it to USGS.

How big was it?

This earthquake released about 120 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 5.8 130,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 89,000× the energy of this one
  3. Around the size people start to feel M 3.0 7.9× the energy of this one
  4. This earthquake M 2.4 about 120 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 37.0813, -122.2715. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Santa Cruz County, CA 25 km (15 mi) WNW of here earthquakes near Santa Cruz County
San Mateo County, CA 38 km (24 mi) SSE of here earthquakes near San Mateo County
Santa Clara County, CA 54 km (33 mi) WSW of here earthquakes near Santa Clara County
Alameda County, CA 70 km (44 mi) SSW of here earthquakes near Alameda County
Contra Costa County, CA 97 km (61 mi) SSW of here earthquakes near Contra Costa County
San Francisco County, CA 98 km (61 mi) SE of here earthquakes near San Francisco County

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

Aftershocks so far

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

  1. 1.8 11 km SSW of La Selva Beach, CA
  2. 1.7 1 km ENE of Woodside, CA
  3. 1.8 1 km E of Woodside, CA
  4. 2.5 1 km ESE of Woodside, CA
  5. 1.5 3 km ESE of Woodside, CA
  6. 1.8 3 km NNE of Portola Valley, CA
  7. 1.7 6 km SSE of Portola Valley, CA
  8. 1.9 3 km NNE of Portola Valley, CA
  9. 1.6 2 km W of Portola Valley, CA
  10. 1.9 7 km SSE of Portola Valley, 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 4.6 on 2026-04-02 — it released about 1,900 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.