QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9md

6km SE of Parkfield, CA

· 4.6 km deep · released about 630 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Luis Obispo County 52 kmKings County 57 kmMonterey County 93 kmSan Benito County 104 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 2.9 (md)
Depth
4.6 km below the surface
Felt
1 report · strongest reported intensity I
Nearest
San Luis Obispo County, 52 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2304 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 630 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 24,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 17,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.5× the energy of this one
  4. This earthquake M 2.9 about 630 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 35.8558, -120.3947. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
San Luis Obispo County, CA 52 km (32 mi) N of here earthquakes near San Luis Obispo County
Kings County, CA 57 km (36 mi) WSW of here earthquakes near Kings County
Monterey County, CA 93 km (58 mi) ESE of here earthquakes near Monterey County
San Benito County, CA 104 km (65 mi) SE of here earthquakes near San Benito County
Fresno County, CA 121 km (75 mi) SSW of here earthquakes near Fresno 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. 2.3 17km NW of Parkfield, CA
  2. 2.1 22km ENE of San Ardo, CA
  3. 1.6 27km NE of San Ardo, CA
  4. 2.1 17km NW of Parkfield, CA
  5. 1.6 6km SSE of Parkfield, CA
  6. 2.2 6km SSE of Parkfield, CA
  7. 2.0 3km ESE of Kettleman City, CA
  8. 1.9 3km SE of Kettleman City, CA
  9. 1.8 6km NNE of Santa Margarita, CA
  10. 2.2 17km N of Coalinga, CA
  11. 1.8 2km SE of Kettleman City, CA
  12. 1.8 2km ESE of Kettleman City, CA
  13. 1.8 19km NW of Parkfield, CA
  14. 2.2 22km NE of San Ardo, CA
  15. 1.6 21km NE of San Ardo, 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 130 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.