QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9md

Earthquake near Shasta Lake, CA

No earthquake was likely felt in Shasta Lake in the 24 hours to 1:49 am PST (09:49 UTC). The last one was M 4.4, 117 km (73 mi) SW, at 3:21 pm PDT on 5 August 2026, estimated intensity II (weak) in town; 122 felt reports to USGS. Every earthquake near Shasta Lake

This page: a magnitude 2.9 earthquake was recorded 25 km (16 mi) north of Shasta Lake, CA, at 10:44 am PDT on 12 May 2021 (17:44 UTC), 20 km deep. 16 people have reported feeling it to USGS.

USGS: 25km N of Shasta Lake, CA

37 km (23 mi) N of Redding, CA · 136 km (84 mi) NNW of Chico, CA

10:44 am PDT, May 12, 2021 · · 20 km deep · released about 780 lb of TNT

10 km30 km60 km120 km N Shasta County 32 kmTrinity County 69 kmSiskiyou County 77 kmTehama County 88 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
10:44 am PDT on 12 May 2021 ()
Where
25 km (16 mi) north of Shasta Lake, CA · earthquakes near Shasta Lake
Magnitude
M 2.9 (md)
Depth
20 km below the surface
Felt
16 reports · strongest reported intensity IV
Nearest
Shasta County, 32 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1938 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 27 km (17 mi) from the epicentre. In Shasta Lake, 25 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: Shasta Lake 25 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 780 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 19,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 14,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.2× the energy of this one
  4. This earthquake M 2.9 about 780 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.1 7km NW of Redding, CA · 31 km S 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 40.9062, -122.3710. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Shasta County, CA 32 km (20 mi) ESE earthquakes near Shasta County
Trinity County, CA 69 km (43 mi) WSW earthquakes near Trinity County
Siskiyou County, CA 77 km (48 mi) N earthquakes near Siskiyou County
Tehama County, CA 88 km (54 mi) S earthquakes near Tehama County

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

Aftershocks so far

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

  1. 1.7 24km N of Shasta Lake, CA
  2. 1.8 11km ESE of Millville, CA
  3. 1.7 27km N of Shasta Lake, CA
  4. 1.8 23km N of Shasta Lake, CA
  5. 1.7 1km NE of Shasta Lake, CA
  6. 1.7 11km NNE of Bella Vista, CA
  7. 2.3 6km ENE of Shasta, CA
  8. 1.6 9km NE of Shasta Lake, CA
  9. 1.6 2km WNW of Shasta Lake, CA
  10. 1.8 12km NE of Bella Vista, CA
  11. 2.5 11km NNE of Bella Vista, CA
  12. 1.9 16km SSE of McCloud, CA
  13. 2.2 6km NW of Redding, CA
  14. 1.7 4km ENE of Shasta, CA
  15. 1.6 12km SE of Dunsmuir, 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.