QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

7 km NW of Parkfield, CA

· 9.5 km deep · released about 1,600 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Luis Obispo County 61 kmKings County 62 kmMonterey County 81 kmSan Benito County 92 kmFresno County 118 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 3.1 (ml)
Depth
9.5 km below the surface
Felt
2 reports · strongest reported intensity II
Nearest
San Luis Obispo County, 61 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 372 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 2 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1,600 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 210,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 9,400× the energy of this one
  3. Magna, Utah 2020 M 5.7 6,700× the energy of this one
  4. This earthquake M 3.1 about 1,600 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.7× 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 35.9390, -120.4895. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
San Luis Obispo County, CA 61 km (38 mi) N of here earthquakes near San Luis Obispo County
Kings County, CA 62 km (39 mi) WSW of here earthquakes near Kings County
Monterey County, CA 81 km (51 mi) ESE of here earthquakes near Monterey County
San Benito County, CA 92 km (57 mi) SE of here earthquakes near San Benito County
Fresno County, CA 118 km (73 mi) SW of here earthquakes near Fresno 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. 1.5 16 km NW of Parkfield, CA
  2. 1.6 2 km SE of Kettleman City, CA
  3. 2.1 5 km NW of Parkfield, CA
  4. 1.7 19 km NW of Parkfield, CA
  5. 1.6 6 km WNW of Avenal, CA
  6. 2.1 10 km ENE of Coalinga, CA
  7. 2.4 9 km S of Huron, CA
  8. 2.4 8 km SSE of Huron, CA
  9. 2.7 8 km S of Huron, CA
  10. 1.9 9 km S of Huron, CA
  11. 2.2 10 km NNW of Cholame, CA
  12. 1.7 22 km NW of Parkfield, CA
  13. 1.9 6 km W of Templeton, CA
  14. 2.2 6 km SW of San Ardo, CA
  15. 1.6 8 km WSW 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 51 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.