QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

4 km NE of San Ardo, CA

· 10 km deep · released about 37 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Monterey County 44 kmSan Benito County 65 kmSan Luis Obispo County 83 kmKings County 96 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
1 report · strongest reported intensity II
Nearest
Monterey County, 44 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 453 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 37 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 5.8 410,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 290,000× the energy of this one
  3. Around the size people start to feel M 3.0 26× the energy of this one
  4. This earthquake M 2.1 about 37 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 36.0493, -120.8832. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Monterey County, CA 44 km (27 mi) ESE of here earthquakes near Monterey County
San Benito County, CA 65 km (40 mi) SSE of here earthquakes near San Benito County
San Luis Obispo County, CA 83 km (52 mi) NNW of here earthquakes near San Luis Obispo County
Kings County, CA 96 km (60 mi) W of here earthquakes near Kings County
Fresno County, CA 135 km (84 mi) SW of here earthquakes near Fresno County
Santa Cruz County, CA 147 km (91 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

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

  1. 1.7 22 km NW of Parkfield, CA
  2. 2.2 6 km SW of San Ardo, CA
  3. 2.0 15 km WNW of Lake Nacimiento, CA
  4. 2.3 15 km WNW of Lake Nacimiento, CA
  5. 1.6 8 km WSW of San Ardo, CA
  6. 1.6 18 km NW of Parkfield, CA
  7. 1.7 11 km SE of Pinnacles, CA
  8. 1.6 13 km WNW of New Idria, CA
  9. 1.7 11 km NW of Parkfield, CA
  10. 1.8 11 km SE of Pinnacles, CA
  11. 1.7 16 km NW of Parkfield, CA
  12. 2.2 10 km SE of Pinnacles, CA
  13. 1.7 15 km W of New Idria, CA
  14. 1.7 23 km NW of Parkfield, CA
  15. 2.1 10 km SE 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 2021-10-25 — it released about 7,700 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.