QuakeIndex

Earthquake · reviewed by a seismologist

M 2.6md

Earthquake near Yosemite Valley, CA

No earthquake was likely felt in Yosemite Valley in the 24 hours to 9:09 am PST (17:09 UTC). The last one was M 2.5, 22 km (14 mi) SE, at 7:51 am PDT on 28 August 2026, estimated intensity II (weak) in town. Every earthquake near Yosemite Valley

This page: a magnitude 2.6 earthquake was recorded 15 km (9 mi) east-southeast of Yosemite Valley, CA, at 9:55 pm PDT on 21 April 2021 (04:55 UTC), 18 km deep. 8 people have reported feeling it to USGS.

USGS: 15km ESE of Yosemite Valley, CA

9:55 pm PDT, Apr 21, 2021 · · 18 km deep · released about 270 lb of TNT

10 km30 km60 km120 km N Mariposa County 45 kmMono County 54 kmTuolumne County 60 kmMadera County 61 kmFresno County 105 kmAlpine County 109 kmCalaveras County 114 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
9:55 pm PDT on 21 April 2021 ()
Where
15 km (9 mi) east-southeast of Yosemite Valley, CA · earthquakes near Yosemite Valley
Magnitude
M 2.6 (md)
Depth
18 km below the surface
Felt
8 reports · strongest reported intensity III
Nearest
Mariposa County, 45 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1958 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 17 km (11 mi) from the epicentre. In Yosemite Valley, 15 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.

Likely felt in: Yosemite Valley 15 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 270 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 57,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 40,000× the energy of this one
  3. Around the size people start to feel M 3.0 3.6× the energy of this one
  4. This earthquake M 2.6 about 270 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 lists 5 earthquakes of M5 or more within 50 km:

  1. 6.0 7 km ENE of Mammoth Lakes, California · 46 km E of this epicentre
  2. 5.9 8 km NNE of Mammoth Lakes, California · 43 km E of this epicentre
  3. 5.8 3 km NE of Mono City, California · 49 km NNE of this epicentre
  4. 5.4 6 km ESE of Mammoth Lakes, California · 46 km E of this epicentre
  5. 5.3 3 km SE of Mammoth Lakes, California · 43 km E of this epicentre

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 37.6902, -119.4183. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Mariposa County, CA 45 km (28 mi) WSW earthquakes near Mariposa County
Mono County, CA 54 km (34 mi) ENE earthquakes near Mono County
Tuolumne County, CA 60 km (38 mi) NW earthquakes near Tuolumne County
Madera County, CA 61 km (38 mi) SSW earthquakes near Madera County
Fresno County, CA 105 km (66 mi) SSW earthquakes near Fresno County
Alpine County, CA 109 km (68 mi) NNW earthquakes near Alpine County

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

Aftershocks so far

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

  1. 1.5 31km SSW of Mammoth Lakes, CA
  2. 1.6 8km E of Mammoth Lakes, CA
  3. 1.5 14km SE of Yosemite Valley, CA
  4. 1.8 24km SSW of Mammoth Lakes, CA
  5. 1.8 24km SSW of Mammoth Lakes, CA
  6. 1.7 27km SW of Mammoth Lakes, CA
  7. 1.7 29km NE of Oakhurst, CA
  8. 2.3 29km NE of Oakhurst, CA
  9. 2.6 11km S of Mammoth Lakes, CA
  10. 2.0 23km ESE of Yosemite Valley, CA
  11. 1.8 11km ESE of Mammoth Lakes, CA
  12. 1.8 12km N of Yosemite Village, CA
  13. 1.7 14km SE of Mammoth Lakes, CA
  14. 1.6 22km NE of North Fork, CA
  15. 1.6 12km SE of Mammoth Lakes, 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.