QuakeIndex

Earthquake · reviewed by a seismologist

M 3.9mw

9km NW of Pinnacles, CA

· 7.7 km deep · released about 11 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Benito County 11 kmMonterey County 41 kmMerced County 79 kmSanta Clara County 82 kmSanta Cruz County 85 kmStanislaus County 109 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 3.9 (mw)
Depth
7.7 km below the surface
Felt
272 reports · strongest reported intensity IV
Measured shaking
intensity IV (ShakeMap)
USGS impact alert
green
Nearest
San Benito County, 11 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1271 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 272 people have reported feeling it to USGS.

How big was it?

This earthquake released about 11 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.9 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 16,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 710× the energy of this one
  3. Magna, Utah 2020 M 5.7 500× the energy of this one
  4. This earthquake M 3.9 about 11 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 22× 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 36.5950, -121.2063. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
San Benito County, CA 11 km (7 mi) W of here earthquakes near San Benito County
Monterey County, CA 41 km (25 mi) NNE of here earthquakes near Monterey County
Merced County, CA 79 km (49 mi) SSW of here earthquakes near Merced County
Santa Clara County, CA 82 km (51 mi) SSE of here earthquakes near Santa Clara County
Santa Cruz County, CA 85 km (53 mi) ESE of here earthquakes near Santa Cruz County
Stanislaus County, CA 109 km (68 mi) S of here earthquakes near Stanislaus County

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

Aftershocks so far

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

  1. 2.4 7km ESE of Pinnacles, CA
  2. 2.4 10km NW of Pinnacles, CA
  3. 1.8 9km SSE of San Juan Bautista, CA
  4. 1.7 19km NW of New Idria, CA
  5. 1.8 31km NNW of New Idria, CA
  6. 1.6 15km SE of Pinnacles, CA
  7. 1.8 3km WSW of San Juan Bautista, CA
  8. 1.9 5km WNW of San Juan Bautista, CA
  9. 1.6 6km W of Hollister, CA
  10. 2.8 9km SSE of San Juan Bautista, CA
  11. 1.5 11km SSW of Tres Pinos, CA
  12. 1.7 22km NE of San Lucas, CA
  13. 1.8 22km NE of San Lucas, CA
  14. 1.8 8km NW of Pinnacles, CA
  15. 2.1 5km SSE of San Juan Bautista, 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 4.7 on 2019-10-15 — it released about 16 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.