QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

Earthquake near Big Pine, CA

No earthquake was likely felt in Big Pine in the 24 hours to 8:25 am PST (16:25 UTC). The last one was M 1.6, 9 km (6 mi) NNE, at 10:07 am PST on 4 November 2026, estimated intensity II (weak) in town. Every earthquake near Big Pine

This page: a magnitude 1.7 earthquake was recorded 6 km (4 mi) east-northeast of Big Pine, CA, at 10:43 am PDT on 28 April 2021 (17:43 UTC), 7.8 km deep.

USGS: 6km ENE of Big Pine, CA

10:43 am PDT, Apr 28, 2021 · · 7.8 km deep · released about 11 lb of TNT

10 km30 km60 km120 km N Esmeralda County 85 kmMono County 100 kmInyo County 101 kmTulare County 117 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
10:43 am PDT on 28 April 2021 ()
Where
6 km (4 mi) east-northeast of Big Pine, CA · earthquakes near Big Pine
Magnitude
M 1.7 (md)
Depth
7.8 km below the surface
Felt
no reports yet
Nearest
Esmeralda County, 85 km NE
Nearest mapped fault
Deep Springs fault, 8 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 2024 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 10 km (6 mi) from the epicentre. In Big Pine, 6 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: Big Pine 6 km, intensity II. Estimated for each town centre; each link is that town's own record.

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 1,400,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 89× 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

The largest earthquake within 50 km since 2016 was M 4.8 on 2016-02-16 — about 40,000 times the energy of this one.

Before 2016, the USGS record lists 17 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 The 1986 Chalfant Valley, California Earthquake · 44 km NNW of this epicentre
  2. 6.1 4 km NNW of Round Valley, California · 46 km NW of this epicentre
  3. 6.1 46km E of Big Pine, California · 40 km E of this epicentre
  4. 6.0 Near Bishop, California · 24 km NW of this epicentre
  5. 5.9 18 km NNE of Mesa, California · 47 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 37.1820, -118.2287. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Esmeralda County, NV 85 km (53 mi) NE earthquakes near Esmeralda County
Mono County, CA 100 km (62 mi) NW earthquakes near Mono County
Inyo County, CA 101 km (63 mi) SE earthquakes near Inyo County
Tulare County, CA 117 km (73 mi) SSW earthquakes near Tulare County

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

Aftershocks so far

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

  1. 1.7 5km ENE of Round Valley, CA
  2. 2.5 2km W of Round Valley, CA
  3. 1.8 2km W of Round Valley, CA
  4. 1.7 39 km ENE of Big Pine, California
  5. 1.5 34 km SE of Dyer, Nevada
  6. 1.9 5km S of Round Valley, CA
  7. 1.5 23 km E of Big Pine, California
  8. 2.1 29km E of Big Pine, CA
  9. 1.8 19km NNW of Deep Springs, CA
  10. 1.7 17km NNE of Independence, CA
  11. 1.8 17km NNE of Independence, CA
  12. 2.4 19km WSW of Wilkerson, CA
  13. 2.2 2km SSE of Round Valley, CA
  14. 1.6 20 km S of Dyer, Nevada
  15. 1.5 3km SSE of Bishop, 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.