QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

Earthquake near Portola, CA

No earthquake was likely felt in Portola in the 24 hours to 12:20 pm PST (20:20 UTC). The last one was M 2.7, 8 km (5 mi) N, at 8:16 am PST on 10 November 2026, estimated intensity III (weak) in town; 9 felt reports to USGS. Every earthquake near Portola

This page: a magnitude 1.5 earthquake was recorded 10 km (6 mi) southwest of Portola, CA, at 10:55 pm PST on 11 January 2022 (06:55 UTC), 14 km deep.

USGS: 1 km ESE of C-Road, California

65 km (41 mi) WNW of Reno, NV

10:55 pm PST, Jan 11, 2022 · · 14 km deep · released about 5.4 lb of TNT

Every earthquake near Portola Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Sierra County 20 kmPlumas County 34 kmNevada County 54 kmPlacer County 78 kmYuba County 86 kmButte County 89 kmStorey County 96 kmCarson City 97 kmLassen County 107 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
10:55 pm PST on 11 January 2022 ()
Where
10 km (6 mi) southwest of Portola, CA · earthquakes near Portola
Magnitude
M 1.5 (ml)
Depth
14 km below the surface
Felt
no reports yet
Nearest
Sierra County, 20 km S
Nearest mapped fault
Mohawk Valley fault, 3 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 1766 days ago

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

At this magnitude and depth it was probably too small to be felt, even directly above it. In Portola, 10 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 5.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,800,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 2,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 180× the energy of this one
  4. This earthquake M 1.5 about 5.4 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 53,000 times the energy of this one.

Before 2016, the USGS record lists 8 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.0 6 km WNW of Verdi, California · 47 km ESE of this epicentre
  2. 5.9 West of Downieville, California · 47 km SW of this epicentre
  3. 5.9 9 km NW of Truckee, California · 48 km SSE of this epicentre
  4. 5.6 5 km NE of Loyalton, California · 32 km E of this epicentre
  5. 5.3 11 km N of Soda Springs, California · 39 km SSE 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 39.7566, -120.5656. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Sierra County, CA 20 km (13 mi) S earthquakes near Sierra County
Plumas County, CA 34 km (21 mi) NW earthquakes near Plumas County
Nevada County, CA 54 km (34 mi) SSW earthquakes near Nevada County
Placer County, CA 78 km (49 mi) S earthquakes near Placer County
Yuba County, CA 86 km (53 mi) SW earthquakes near Yuba County
Butte County, CA 89 km (56 mi) W earthquakes near Butte County

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

Aftershocks so far

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

  1. 1.6 Northern California
  2. 1.6 8 km SSE of Johnsville, California
  3. 1.6 7 km S of Plumas Eureka (historical), California
  4. 1.5 9 km SSE of Beckwourth, California
  5. 1.6 1 km NNE of Paxton, California
  6. 1.5 1 km WNW of Keddie, California
  7. 1.7 1 km W of Keddie, California
  8. 1.6 0 km E of Paxton, California
  9. 2.8 3km N of Greenhorn, CA
  10. 1.6 5 km NNW of Plumas Eureka (historical), California
  11. 1.5 1 km SW of Spring Garden, California
  12. 2.0 12km NW of Truckee, CA
  13. 2.2 4km NE of Lake Davis, CA
  14. 3.1 10km ESE of Loyalton, CA
  15. 2.3 4km S of Meadow Valley, 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.