QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0ml

Earthquake near East Quincy, CA

No earthquake was likely felt in East Quincy in the 24 hours to 1:23 pm PST (21:23 UTC). The last one was M 2.3, 6 km (3 mi) N, at 5:11 am PST on 7 November 2026, estimated intensity II (weak) in town. Every earthquake near East Quincy

This page: a magnitude 3.0 earthquake was recorded 23 km (15 mi) southeast of East Quincy, CA, at 12:30 am PDT on 27 June 2026 (07:30 UTC), less than 1 km deep. 28 people have reported feeling it to USGS.

USGS: 4 km WSW of Johnsville, CA

12:30 am PDT, Jun 27, 2026 · · -1.6 km deep · released about 990 lb of TNT

10 km30 km60 km120 km N Plumas County 27 kmSierra County 28 kmNevada County 52 kmButte County 75 kmYuba County 76 kmPlacer County 78 kmLassen County 106 kmCarson City 109 kmStorey County 110 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
12:30 am PDT on 27 June 2026 ()
Where
23 km (15 mi) southeast of East Quincy, CA · earthquakes near East Quincy
Magnitude
M 3.0 (ml)
Depth
-1.6 km below the surface
Felt
28 reports · strongest reported intensity III
Nearest
Plumas County, 27 km NNW
Nearest mapped fault
Mohawk Valley fault, 9 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 58 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 37 km (23 mi) from the epicentre. In East Quincy, 23 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: Portola 23 km, intensity II · East Quincy 23 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 990 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 340,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 15,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 11,000× the energy of this one
  4. This earthquake M 3.0 about 990 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 4.7 on 2021-05-07 — about 290 times the energy of this one.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

  1. 5.9 West of Downieville, California · 37 km SW of this epicentre
  2. 5.6 5 km NE of Loyalton, California · 46 km E of this epicentre
  3. 5.3 11 km N of Soda Springs, California · 47 km SE of this epicentre
  4. 5.2 3 km N of Blairsden, California · 11 km ENE of this epicentre
  5. 5.0 Nevada County, California · 43 km SSW 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 39.7640, -120.7347. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Plumas County, CA 27 km (16 mi) NNW earthquakes near Plumas County
Sierra County, CA 28 km (17 mi) SE earthquakes near Sierra County
Nevada County, CA 52 km (32 mi) S earthquakes near Nevada County
Butte County, CA 75 km (47 mi) W earthquakes near Butte County
Yuba County, CA 76 km (47 mi) SW earthquakes near Yuba County
Placer County, CA 78 km (49 mi) S earthquakes near Placer County

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

Aftershocks so far

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

  1. 2.7 1 km N of Lake Davis, CA
  2. 2.3 6 km N of East Quincy, CA
  3. 2.4 10 km N of Greenhorn, CA
  4. 2.3 2 km ENE of Keddie, CA
  5. 2.2 9 km S of Johnsville, CA
  6. 2.1 7 km NE of Lake Davis, CA
  7. 2.1 8 km WNW of La Porte, CA
  8. 2.6 8 km NE of Lake Davis, CA
  9. 2.3 8 km NE of Lake Davis, CA
  10. 2.2 8 km NE of Lake Davis, CA
  11. 2.0 5 km SSW of Cromberg, 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.