QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4md

Earthquake near Madera, CA

No earthquake was likely felt in Madera in the 24 hours to 11:00 pm PST (07:00 UTC). The last one was M 2.6, 5 km (3 mi) WNW, at 5:14 am PDT on 29 October 2026, estimated intensity II (weak) in town. Every earthquake near Madera

This page: a magnitude 2.4 earthquake was recorded 38 km (23 mi) north of Madera, CA, at 5:30 am PST on 18 November 2021 (13:30 UTC), 21 km deep. 1 person has reported feeling it to USGS.

USGS: 21km SSW of Bootjack, CA

60 km (37 mi) NNW of Fresno, CA · 37 km (23 mi) NNE of Madera, CA

5:30 am PST, Nov 18, 2021 · · 21 km deep · released about 100 lb of TNT

10 km30 km60 km120 km N Madera County 24 kmMariposa County 32 kmMerced County 65 kmFresno County 67 kmTuolumne County 81 kmStanislaus County 93 kmCalaveras County 111 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
5:30 am PST on 18 November 2021 ()
Where
38 km (23 mi) north of Madera, CA · earthquakes near Madera
Magnitude
M 2.4 (md)
Depth
21 km below the surface
Felt
1 report
Nearest
Madera County, 24 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1819 days ago

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

At this magnitude and depth it was probably too small to be felt, even directly above it. In Madera, 38 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Earthquakes near other towns within 30 km: Mariposa, Yosemite Lakes, Le Grand, Ahwahnee, Coarsegold, Planada.

How big was it?

This earthquake released about 100 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 140,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 100,000× the energy of this one
  3. Around the size people start to feel M 3.0 9.1× the energy of this one
  4. This earthquake M 2.4 about 100 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.

For this area

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 37.2955, -119.9997. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Madera County, CA 24 km (15 mi) ESE earthquakes near Madera County
Mariposa County, CA 32 km (20 mi) NNE earthquakes near Mariposa County
Merced County, CA 65 km (40 mi) W earthquakes near Merced County
Fresno County, CA 67 km (42 mi) SSE earthquakes near Fresno County
Tuolumne County, CA 81 km (50 mi) N earthquakes near Tuolumne County
Stanislaus County, CA 93 km (58 mi) WNW earthquakes near Stanislaus 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. 3.0 19km SSW of Mariposa, CA
  2. 1.7 5km ENE of Bonadelle Ranchos-Madera Ranchos, CA
  3. 1.8 5km ENE of Bonadelle Ranchos-Madera Ranchos, CA
  4. 2.3 21km S of Mariposa, CA
  5. 2.0 5km ENE of Bonadelle Ranchos-Madera Ranchos, CA
  6. 2.8 14km ENE of Midpines, CA
  7. 2.1 17km SSW of Mariposa, CA
  8. 2.2 7km ENE of Bonadelle Ranchos-Madera Ranchos, CA
  9. 2.0 5km ENE of Bonadelle Ranchos-Madera Ranchos, CA
  10. 1.8 5km E of Bonadelle Ranchos-Madera Ranchos, CA
  11. 2.1 6km ESE of Coarsegold, CA
  12. 1.7 8km SSE of Bootjack, CA
  13. 2.1 6km ENE of Bonadelle Ranchos-Madera Ranchos, CA
  14. 2.1 20km ENE of Le Grand, CA
  15. 2.0 6km NW of Friant, 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.