QuakeIndex

quarry blast · reviewed by a seismologist

M 1.8md

5km E of Bonadelle Ranchos-Madera Ranchos, CA

· -0.6 km deep · released about 14 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Madera County 25 kmFresno County 29 kmMariposa County 65 kmMerced County 83 kmKings County 102 kmTuolumne County 115 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 1.8 (md)
Depth
-0.6 km below the surface
Felt
no reports yet
Nearest
Madera County, 25 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1517 days ago

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

USGS catalogues this as quarry blast, not an earthquake.

How big was it?

This earthquake released about 14 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 760,000× the energy of this one
  3. Around the size people start to feel M 3.0 68× the energy of this one
  4. This earthquake M 1.8 about 14 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 36.9905, -119.8182. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Madera County, CA 25 km (16 mi) SSW of here earthquakes near Madera County
Fresno County, CA 29 km (18 mi) NNW of here earthquakes near Fresno County
Mariposa County, CA 65 km (41 mi) S of here earthquakes near Mariposa County
Merced County, CA 83 km (52 mi) ESE of here earthquakes near Merced County
Kings County, CA 102 km (63 mi) N of here earthquakes near Kings County
Tuolumne County, CA 115 km (72 mi) S of here earthquakes near Tuolumne County

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

Aftershocks so far

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

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