QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

20km ENE of Le Grand, CA

· 18 km deep · released about 40 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Madera County 27 kmMariposa County 33 kmMerced County 62 kmFresno County 68 kmTuolumne County 82 kmStanislaus County 91 kmCalaveras County 110 kmSan Benito County 120 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
18 km below the surface
Felt
no reports yet
Nearest
Madera County, 27 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1542 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 37.2907, -120.0363. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Madera County, CA 27 km (17 mi) WNW of here earthquakes near Madera County
Mariposa County, CA 33 km (21 mi) SSW of here earthquakes near Mariposa County
Merced County, CA 62 km (38 mi) E of here earthquakes near Merced County
Fresno County, CA 68 km (42 mi) NNW of here earthquakes near Fresno County
Tuolumne County, CA 82 km (51 mi) S of here earthquakes near Tuolumne County
Stanislaus County, CA 91 km (56 mi) ESE of here earthquakes near Stanislaus County

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

Aftershocks so far

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

  1. 2.0 11km S of Mariposa, CA
  2. 2.0 6km ENE of Bonadelle Ranchos-Madera Ranchos, CA
  3. 2.2 9km SSW of Mariposa, CA
  4. 1.6 10km SSW of Mariposa, CA
  5. 1.6 12km NNW of Friant, CA
  6. 2.3 21km SSW of Bootjack, CA
  7. 1.8 5km ENE of Bonadelle Ranchos-Madera Ranchos, CA
  8. 1.6 11km SSW of Mariposa, CA
  9. 2.1 11km SSW of Mariposa, CA
  10. 2.0 2km WSW of Oakhurst, CA
  11. 1.9 12km S of Mariposa, CA
  12. 1.6 9km W of Ahwahnee, CA
  13. 2.3 21km SSW of Mariposa, CA
  14. 2.6 5km ENE of Bonadelle Ranchos-Madera Ranchos, CA
  15. 3.4 21km ENE of Le Grand, 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.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.