QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Yosemite Valley, CA

No earthquake was likely felt in Yosemite Valley in the 24 hours to 8:09 am PST (16:09 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 1.8 earthquake was recorded 20 km (13 mi) southeast of Yosemite Valley, CA, at 12:37 pm PDT on 29 October 2020 (19:37 UTC), 9.4 km deep.

USGS: 20km SE of Yosemite Valley, CA

12:37 pm PDT, Oct 29, 2020 · · 9.4 km deep · released about 13 lb of TNT

10 km30 km60 km120 km N Mariposa County 47 kmMono County 55 kmMadera County 57 kmTuolumne County 66 kmFresno County 100 kmAlpine County 115 kmCalaveras County 119 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
12:37 pm PDT on 29 October 2020 ()
Where
20 km (13 mi) southeast of Yosemite Valley, CA · earthquakes near Yosemite Valley
Magnitude
M 1.8 (md)
Depth
9.4 km below the surface
Felt
no reports yet
Nearest
Mariposa County, 47 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2205 days ago

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

At this magnitude and depth, people at rest would likely notice it out to about 9 km (6 mi) from the epicentre. In Yosemite Valley, 20 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.

How big was it?

This earthquake released about 13 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 5.7 810,000× the energy of this one
  3. Around the size people start to feel M 3.0 72× the energy of this one
  4. This earthquake M 1.8 about 13 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

The largest earthquake within 50 km since 2016 was M 4.0 on 2020-04-05 — about 2,700 times the energy of this one.

Before 2016, the USGS record lists 11 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.1 11 km WNW of Aspen Springs, California · 49 km E of this epicentre
  2. 6.0 7 km ENE of Mammoth Lakes, California · 43 km E of this epicentre
  3. 5.9 8 km NNE of Mammoth Lakes, California · 42 km ENE of this epicentre
  4. 5.9 11 km SE of Mammoth Lakes, California · 46 km E of this epicentre
  5. 5.7 12 km ESE of Mammoth Lakes, California · 49 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 37.6377, -119.3875. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Mariposa County, CA 47 km (29 mi) W earthquakes near Mariposa County
Mono County, CA 55 km (34 mi) NE earthquakes near Mono County
Madera County, CA 57 km (36 mi) SW earthquakes near Madera County
Tuolumne County, CA 66 km (41 mi) NW earthquakes near Tuolumne County
Fresno County, CA 100 km (62 mi) SSW earthquakes near Fresno County
Alpine County, CA 115 km (72 mi) NNW earthquakes near Alpine County

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

Aftershocks so far

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

  1. 1.7 8km E of Mammoth Lakes, CA
  2. 1.6 19km SE of Yosemite Valley, CA
  3. 1.8 9km ESE of Mammoth Lakes, CA
  4. 1.7 9km E of Mammoth Lakes, CA
  5. 1.7 12km E of Mammoth Lakes, CA
  6. 1.9 11km E of Mammoth Lakes, CA
  7. 1.7 21km ESE of Yosemite Valley, CA
  8. 2.4 19km SE of Yosemite Valley, CA
  9. 1.7 23km SE of Yosemite Valley, CA
  10. 1.6 23km SE of Yosemite Valley, CA
  11. 2.5 20km SE of Yosemite Valley, CA
  12. 1.6 4km E of Mammoth Lakes, CA
  13. 2.1 4km E of Mammoth Lakes, CA
  14. 1.7 4km E of Mammoth Lakes, CA
  15. 1.6 4km E 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.