QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

Earthquake near Madera, CA

No earthquake was likely felt in Madera in the 24 hours to 3:26 am PST (11:26 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 1.7 earthquake was recorded 43 km (27 mi) north-northeast of Madera, CA, at 10:53 am PST on 2 February 2021 (18:53 UTC), 24 km deep.

USGS: 15km S of Bootjack, CA

61 km (38 mi) N of Fresno, CA · 44 km (27 mi) NNE of Madera, CA

10:53 am PST, Feb 2, 2021 · · 24 km deep · released about 11 lb of TNT

10 km30 km60 km120 km N Madera County 19 kmMariposa County 27 kmFresno County 67 kmMerced County 75 kmTuolumne County 77 kmStanislaus County 101 kmMono County 111 kmCalaveras County 112 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
10:53 am PST on 2 February 2021 ()
Where
43 km (27 mi) north-northeast of Madera, CA · earthquakes near Madera
Magnitude
M 1.7 (md)
Depth
24 km below the surface
Felt
no reports yet
Nearest
Madera County, 19 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2102 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, 43 km away, the estimate is intensity I (not felt). 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: Ahwahnee, Mariposa, Yosemite Lakes, Coarsegold, Oakhurst, Midpines.

How big was it?

This earthquake released about 11 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,300,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 930,000× the energy of this one
  3. Around the size people start to feel M 3.0 83× the energy of this one
  4. This earthquake M 1.7 about 11 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 37.3280, -119.8970. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Madera County, CA 19 km (11 mi) SE earthquakes near Madera County
Mariposa County, CA 27 km (17 mi) N earthquakes near Mariposa County
Fresno County, CA 67 km (41 mi) SSE earthquakes near Fresno County
Merced County, CA 75 km (46 mi) W earthquakes near Merced County
Tuolumne County, CA 77 km (48 mi) N earthquakes near Tuolumne County
Stanislaus County, CA 101 km (63 mi) WNW earthquakes near Stanislaus County

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

Aftershocks so far

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

  1. 2.1 29km ENE of Oakhurst, CA
  2. 1.5 29km NE of Oakhurst, CA
  3. 1.5 29km NE of Oakhurst, CA
  4. 1.9 7km NE of Bonadelle Ranchos-Madera Ranchos, CA
  5. 1.6 7km NE of Bonadelle Ranchos-Madera Ranchos, CA
  6. 1.8 6km NNW of Ahwahnee, CA
  7. 2.0 6km SW of North Fork, CA
  8. 2.2 21km SSW of Mariposa, CA
  9. 2.4 8km ENE of North Fork, CA
  10. 2.0 6km NE of Oakhurst, CA
  11. 2.4 20km WNW of Yosemite Lakes, CA
  12. 1.7 29km NE of Oakhurst, CA
  13. 1.6 14km SW of Bootjack, CA
  14. 1.7 30km NE of Oakhurst, CA
  15. 1.9 30km NE of Oakhurst, 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.