QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4md

9km ENE of Morgan Hill, CA

· -0.4 km deep · released about 120 lb of TNT

10 km30 km60 km120 km N Santa Clara County 13 kmSanta Cruz County 43 kmAlameda County 63 kmStanislaus County 66 kmSan Benito County 74 kmMerced County 74 kmSan Mateo County 77 kmSan Joaquin County 90 kmContra Costa County 91 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
-0.4 km below the surface
Felt
5 reports · strongest reported intensity IV
Nearest
Santa Clara County, 13 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1629 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 5 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 5.8 120,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 86,000× the energy of this one
  3. Around the size people start to feel M 3.0 7.7× 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 37.1603, -121.5587. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Santa Clara County, CA 13 km (8 mi) ESE of here earthquakes near Santa Clara County
Santa Cruz County, CA 43 km (27 mi) ENE of here earthquakes near Santa Cruz County
Alameda County, CA 63 km (39 mi) SSE of here earthquakes near Alameda County
Stanislaus County, CA 66 km (41 mi) SW of here earthquakes near Stanislaus County
San Benito County, CA 74 km (46 mi) NW of here earthquakes near San Benito County
Merced County, CA 74 km (46 mi) W of here earthquakes near Merced County

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

Aftershocks so far

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

  1. 1.8 4km SSW of San Juan Bautista, CA
  2. 1.6 10km NE of San Martin, CA
  3. 2.0 8km NNE of Day Valley, CA
  4. 1.5 9km NNE of Alum Rock, CA
  5. 1.5 3km E of Aromas, CA
  6. 2.0 15km N of Morgan Hill, CA
  7. 1.7 12km ESE of Gilroy, CA
  8. 1.8 8km NE of Alum Rock, CA
  9. 1.6 9km NE of Alum Rock, CA
  10. 1.7 8km NE of Alum Rock, CA
  11. 1.8 8km NE of Alum Rock, CA
  12. 3.3 10km NE of Morgan Hill, CA
  13. 2.0 8km ENE of Alum Rock, CA
  14. 1.5 15km N of Morgan Hill, CA
  15. 1.7 2km ENE 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 4.2 on 2021-01-17 — it released about 480 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.