QuakeIndex

Earthquake · reviewed by a seismologist

M 4.0mw

6km NW of Pinnacles, CA

· 8.5 km deep · released about 18 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Benito County 9 kmMonterey County 39 kmMerced County 80 kmSanta Clara County 85 kmSanta Cruz County 88 kmStanislaus 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 4.0 (mw)
Depth
8.5 km below the surface
Felt
265 reports · strongest reported intensity IV
Measured shaking
intensity V (ShakeMap)
USGS impact alert
green
Tsunami
USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Nearest
San Benito County, 9 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1786 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 265 people have reported feeling it to USGS.

How big was it?

This earthquake released about 18 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 9,400× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 420× the energy of this one
  3. Magna, Utah 2020 M 5.7 300× the energy of this one
  4. This earthquake M 4.0 about 18 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 38× 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 36.5782, -121.1828. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
San Benito County, CA 9 km (6 mi) WSW of here earthquakes near San Benito County
Monterey County, CA 39 km (24 mi) NNE of here earthquakes near Monterey County
Merced County, CA 80 km (50 mi) SSW of here earthquakes near Merced County
Santa Clara County, CA 85 km (53 mi) SSE of here earthquakes near Santa Clara County
Santa Cruz County, CA 88 km (55 mi) ESE of here earthquakes near Santa Cruz County
Stanislaus County, CA 111 km (69 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

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

  1. 2.0 11km SSW of Ridgemark, CA
  2. 2.1 24km NE of King City, CA
  3. 1.7 14km SSE of Tres Pinos, CA
  4. 1.7 6km NNE of Pinnacles, CA
  5. 1.6 12km SE of Pinnacles, CA
  6. 2.1 6km S of San Juan Bautista, CA
  7. 1.6 15km SE of Pinnacles, CA
  8. 1.9 13km S of Tres Pinos, CA
  9. 2.2 13km S of Tres Pinos, CA
  10. 1.9 14km WNW of Pinnacles, CA
  11. 1.8 14km WNW of Pinnacles, CA
  12. 2.4 6km SE of Pinnacles, CA
  13. 2.0 7km ESE of Pinnacles, CA
  14. 1.5 17km SSE of Tres Pinos, CA
  15. 3.7 14km WNW of Pinnacles, 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 9.8 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.