QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Chico, CA

No earthquake was likely felt in Chico in the 24 hours to 4:42 am PST (12:42 UTC). The last one was M 4.4, 120 km (75 mi) W, at 6:14 pm PDT on 10 July 2026, estimated intensity II (weak) in town; 66 felt reports to USGS. Every earthquake near Chico

This page: a magnitude 1.8 earthquake was recorded 2 km (2 mi) north-northeast of Chico, CA, at 7:58 am PDT on 22 March 2020 (14:58 UTC), 29 km deep.

USGS: 1km NNE of Chico, CA

in Chico, CA

7:58 am PDT, Mar 22, 2020 · · 29 km deep · released about 16 lb of TNT

10 km30 km60 km120 km N Butte County 22 kmGlenn County 52 kmTehama County 54 kmYuba County 68 kmColusa County 73 kmSutter County 80 kmPlumas County 90 kmNevada County 104 kmLake County 106 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
7:58 am PDT on 22 March 2020 ()
Where
2 km (2 mi) north-northeast of Chico, CA · earthquakes near Chico
Magnitude
M 1.8 (md)
Depth
29 km below the surface
Felt
no reports yet
Nearest
Butte County, 22 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2422 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 Chico, 2 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: Durham, Hamilton City, Paradise, Forest Ranch, Magalia.

How big was it?

This earthquake released about 16 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 930,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 660,000× the energy of this one
  3. Around the size people start to feel M 3.0 59× the energy of this one
  4. This earthquake M 1.8 about 16 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 3 earthquakes of M5 or more within 50 km:

  1. 5.7 The 1975 Oroville, California Earthquake · 43 km SE of this epicentre
  2. 5.2 4 km E of Palermo, California · 46 km SE of this epicentre
  3. 5.1 5 km ENE of Palermo, California · 45 km SE 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 39.7498, -121.8302. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Butte County, CA 22 km (13 mi) ESE earthquakes near Butte County
Glenn County, CA 52 km (32 mi) WSW earthquakes near Glenn County
Tehama County, CA 54 km (34 mi) NW earthquakes near Tehama County
Yuba County, CA 68 km (42 mi) SE earthquakes near Yuba County
Colusa County, CA 73 km (45 mi) SSW earthquakes near Colusa County
Sutter County, CA 80 km (50 mi) S earthquakes near Sutter 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. 2.7 2km NNW of Chico, CA
  2. 2.8 15km E of Willows, CA
  3. 3.8 15km E of Willows, CA
  4. 1.7 30km NNW of Forest Ranch, CA
  5. 1.8 4km SSE of Hamilton City, CA
  6. 2.1 3km W of Chico, CA
  7. 1.8 10km N of Oroville, CA
  8. 2.6 14km SSE of Willows, CA
  9. 1.8 5km SE of Hamilton City, CA
  10. 1.7 27km ENE of Los Molinos, CA
  11. 2.2 16km E of Willows, CA
  12. 3.9 15km E of Willows, CA
  13. 1.9 16km NW of Biggs, CA
  14. 1.8 16km E of Willows, CA
  15. 2.1 13km ESE of Willows, 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.