QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5md

16km SSW of Bonny Doon, CA

· 5.1 km deep · released about 190 lb of TNT

10 km30 km60 km120 km N Santa Cruz County 22 kmSan Mateo County 58 kmSanta Clara County 58 kmAlameda County 86 kmSan Benito County 106 kmMonterey County 110 kmContra Costa County 115 kmSan Francisco County 116 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
5.1 km below the surface
Felt
10 reports · strongest reported intensity II
Nearest
Santa Cruz County, 22 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1744 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 10 people have reported feeling it to USGS.

How big was it?

This earthquake released about 190 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 80,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 57,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.1× the energy of this one
  4. This earthquake M 2.5 about 190 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 36.9082, -122.2165. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Santa Cruz County, CA 22 km (14 mi) WSW of here earthquakes near Santa Cruz County
San Mateo County, CA 58 km (36 mi) SSE of here earthquakes near San Mateo County
Santa Clara County, CA 58 km (36 mi) SW of here earthquakes near Santa Clara County
Alameda County, CA 86 km (54 mi) SSW of here earthquakes near Alameda County
San Benito County, CA 106 km (66 mi) WNW of here earthquakes near San Benito County
Monterey County, CA 110 km (68 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

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

  1. 1.8 6km SSE of Portola Valley, CA
  2. 2.0 6km SSE of Portola Valley, CA
  3. 2.1 6km SSE of Portola Valley, CA
  4. 1.9 6km SSE of Portola Valley, CA
  5. 1.7 6km SSE of Portola Valley, CA
  6. 1.5 14km WSW of Portola Valley, CA
  7. 2.4 13km WSW of Santa Cruz, CA
  8. 1.6 3km SSW of Monte Sereno, CA
  9. 1.8 6km SSE of Portola Valley, CA
  10. 1.9 6km SSE of Portola Valley, CA
  11. 1.9 6km SSE of Portola Valley, CA
  12. 1.7 7km SSE of Portola Valley, CA
  13. 1.8 6km SSE of Portola Valley, CA
  14. 1.6 5km NNW of Aromas, CA
  15. 2.0 6km 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.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.