QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

8km E of San Ardo, CA

· 10 km deep · released about 40 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Monterey County 50 kmSan Benito County 69 kmSan Luis Obispo County 79 kmKings County 90 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 2.1 (md)
Depth
10 km below the surface
Felt
no reports yet
Nearest
Monterey County, 50 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1954 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 40 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 380,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 270,000× the energy of this one
  3. Around the size people start to feel M 3.0 24× the energy of this one
  4. This earthquake M 2.1 about 40 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 36.0310, -120.8205. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Monterey County, CA 50 km (31 mi) ESE of here earthquakes near Monterey County
San Benito County, CA 69 km (43 mi) SSE of here earthquakes near San Benito County
San Luis Obispo County, CA 79 km (49 mi) NNW of here earthquakes near San Luis Obispo County
Kings County, CA 90 km (56 mi) W of here earthquakes near Kings County
Fresno County, CA 132 km (82 mi) SW of here earthquakes near Fresno County
Santa Cruz County, CA 152 km (95 mi) SE of here earthquakes near Santa Cruz County

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

Aftershocks so far

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

  1. 1.7 20km SW of New Idria, CA
  2. 1.8 25km NW of Parkfield, CA
  3. 1.9 23km NW of Parkfield, CA
  4. 1.6 19km NNW of Coalinga, CA
  5. 1.6 5km NW of Parkfield, CA
  6. 2.4 19km NNW of San Simeon, CA
  7. 2.6 2km SSE of Parkfield, CA
  8. 2.1 13km NW of Parkfield, CA
  9. 1.9 23km NNE of San Ardo, CA
  10. 1.6 16km SE of Pinnacles, CA
  11. 1.7 20km NW of Parkfield, CA
  12. 1.9 23km SE of Pinnacles, CA
  13. 2.3 3km SE of San Ardo, CA
  14. 2.8 9km WNW of Templeton, CA
  15. 2.3 20km SW of New Idria, 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 4.3 on 2019-12-17 — it released about 2,100 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.