QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

Earthquake near West Bishop, CA

No earthquake was likely felt in West Bishop in the 24 hours to 6:45 am PST (14:45 UTC). The last one was M 2.3, 15 km (10 mi) WNW, at 4:24 pm PDT on 24 October 2026, estimated intensity II (weak) in town. Every earthquake near West Bishop

This page: a magnitude 1.9 earthquake was recorded 13 km (8 mi) west-northwest of West Bishop, CA, at 7:50 am PST on 24 January 2021 (15:50 UTC), 8.7 km deep.

USGS: 2km ENE of Round Valley, CA

7:50 am PST, Jan 24, 2021 · · 8.7 km deep · released about 25 lb of TNT

10 km30 km60 km120 km N Mono County 61 kmEsmeralda County 93 kmMadera County 106 kmMariposa County 118 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
7:50 am PST on 24 January 2021 ()
Where
13 km (8 mi) west-northwest of West Bishop, CA · earthquakes near West Bishop
Magnitude
M 1.9 (md)
Depth
8.7 km below the surface
Felt
no reports yet
Nearest
Mono County, 61 km NNW
Nearest mapped fault
Round Valley fault, 12 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2113 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 13 km (8 mi) from the epicentre. In West Bishop, 13 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: Dixon Lane-Meadow Creek, Bishop.

How big was it?

This earthquake released about 25 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 620,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 440,000× the energy of this one
  3. Around the size people start to feel M 3.0 39× the energy of this one
  4. This earthquake M 1.9 about 25 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 4.8 on 2016-02-16 — about 18,000 times the energy of this one.

Before 2016, the USGS record lists 39 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 The 1986 Chalfant Valley, California Earthquake · 18 km NE of this epicentre
  2. 6.2 9 km SW of Aspen Springs, California · 22 km WNW of this epicentre
  3. 6.1 11 km WNW of Aspen Springs, California · 29 km NW of this epicentre
  4. 6.1 8 km W of Aspen Springs, California · 25 km NW of this epicentre
  5. 6.1 4 km NNW of Round Valley, California · 5 km NNW 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 37.4208, -118.5833. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Mono County, CA 61 km (38 mi) NNW earthquakes near Mono County
Esmeralda County, NV 93 km (58 mi) ENE earthquakes near Esmeralda County
Madera County, CA 106 km (66 mi) WSW earthquakes near Madera County
Mariposa County, CA 118 km (74 mi) W earthquakes near Mariposa County
Fresno County, CA 120 km (75 mi) SW earthquakes near Fresno County
Inyo County, CA 142 km (88 mi) SE earthquakes near Inyo 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. 1.8 13km SE of Mammoth Lakes, CA
  2. 2.0 11km SE of Mammoth Lakes, CA
  3. 1.9 18km SW of Toms Place, CA
  4. 2.3 22km SW of Big Pine, CA
  5. 1.8 17km SSE of Mammoth Lakes, CA
  6. 1.8 9km W of Toms Place, CA
  7. 1.8 9km WSW of Toms Place, CA
  8. 2.8 19km SW of Toms Place, CA
  9. 2.2 19km SW of Toms Place, CA
  10. 2.1 13km W of Toms Place, CA
  11. 1.6 12km NNE of Round Valley, CA
  12. 1.5 17km SW of Toms Place, CA
  13. 2.7 17km SW of Toms Place, CA
  14. 1.5 11km WNW of Toms Place, CA
  15. 1.9 14km 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.