QuakeIndex

Earthquake · reviewed by a seismologist

M 3.4mw

6km SW of Ridgemark, CA

· 11 km deep · released about 1.9 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Benito County 35 kmSanta Clara County 55 kmSanta Cruz County 59 kmMonterey County 60 kmMerced County 77 kmStanislaus County 95 kmAlameda County 106 kmSan Mateo County 111 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 3.4 (mw)
Depth
11 km below the surface
Felt
75 reports · strongest reported intensity IV
Measured shaking
intensity III (ShakeMap)
Nearest
San Benito County, 35 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2910 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 75 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1.9 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.4 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 89,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 4,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 2,800× the energy of this one
  4. This earthquake M 3.4 about 1.9 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 4× more

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 36.7748, -121.4168. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
San Benito County, CA 35 km (22 mi) WNW of here earthquakes near San Benito County
Santa Clara County, CA 55 km (34 mi) SSE of here earthquakes near Santa Clara County
Santa Cruz County, CA 59 km (37 mi) ESE of here earthquakes near Santa Cruz County
Monterey County, CA 60 km (37 mi) N of here earthquakes near Monterey County
Merced County, CA 77 km (48 mi) SW of here earthquakes near Merced County
Stanislaus County, CA 95 km (59 mi) SSW of here earthquakes near Stanislaus County

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

Aftershocks so far

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

  1. 2.2 6km NNW of Pinnacles, CA
  2. 2.4 10km SE of Pinnacles, CA
  3. 2.5 3km WSW of San Juan Bautista, CA
  4. 2.9 4km NNW of Pinnacles, CA
  5. 1.7 23km SW of Los Banos, CA
  6. 1.7 11km WSW of Ridgemark, CA
  7. 2.0 11km S of Tres Pinos, CA
  8. 2.0 1km NE of Pinnacles, CA
  9. 2.4 24km SW of Gustine, CA
  10. 1.6 16km NW of Pinnacles, CA
  11. 1.6 7km NE of Ridgemark, CA
  12. 1.8 13km S of Tres Pinos, CA
  13. 2.5 9km NE of San Martin, CA
  14. 1.8 9km N of Pinnacles, CA
  15. 2.5 16km SSE of Tres Pinos, 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 2017-11-13 — it released about 59 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.