Earthquake · reviewed by a seismologist
M 1.8md
Earthquake near Willows, CA
No earthquake was likely felt in Willows in the 24 hours to 3:22 am PST (11:22 UTC). The last one was M 4.0, 65 km (40 mi) W, at 5:01 am PDT on 28 October 2026, estimated intensity II (weak) in town; 14 felt reports to USGS. Every earthquake near Willows
This page: a magnitude 1.8 earthquake was recorded 16 km (10 mi) east of Willows, CA, at 10:16 pm PDT on 17 July 2020 (05:16 UTC), 20 km deep.
USGS: 16km E of Willows, CA
30 km (18 mi) SSW of Chico, CA · 117 km (73 mi) NNW of Sacramento, CA
- When
- 10:16 pm PDT on 17 July 2020 ()
- Where
- 16 km (10 mi) east of Willows, CA · earthquakes near Willows
- Magnitude
- M 1.8 (md)
- Depth
- 20 km below the surface
- Felt
- no reports yet
- Nearest
- Glenn County, 35 km WNW
- Nearest mapped fault
- Great Valley thrust fault system, 25 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 2308 days ago
Earthquake alerts for Willows, CA
Get a notification in this browser when USGS records an earthquake near Willows, CA. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
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 Willows, 16 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, Chico, Orland, Biggs.
How big was it?
This earthquake released about 13 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.
- Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
- Magna, Utah 2020 M 5.7 810,000× the energy of this one
- Around the size people start to feel M 3.0 72× the energy of this one
- This earthquake M 1.8 about 13 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:
- 5.7 The 1975 Oroville, California Earthquake · 41 km ESE of this epicentre
- 5.2 4 km E of Palermo, California · 46 km ESE of this epicentre
- 5.1 5 km ENE of Palermo, California · 46 km ESE 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 39.5363, -122.0060. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Glenn County, CA | 35 km (22 mi) | WNW | earthquakes near Glenn County |
| Butte County, CA | 37 km (23 mi) | ENE | earthquakes near Butte County |
| Colusa County, CA | 45 km (28 mi) | SSW | earthquakes near Colusa County |
| Sutter County, CA | 61 km (38 mi) | SSE | earthquakes near Sutter County |
| Yuba County, CA | 64 km (40 mi) | ESE | earthquakes near Yuba County |
| Tehama County, CA | 68 km (42 mi) | NNW | earthquakes near Tehama County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
59 earthquakes have been recorded within 50 km since this one.
- 1.8 10km N of Oroville, CA
- 1.7 9km W of Williams, CA
- 2.1 9km WSW of Williams, CA
- 2.0 11km NNW of Chico, CA
- 1.7 14km S of Hamilton City, CA
- 2.2 15km ENE of Willows, CA
- 2.0 10km N of Oroville, CA
- 2.9 6km NNE of Hamilton City, CA
- 2.5 6km NW of Chico, CA
- 2.5 5km NNE of Hamilton City, CA
- 2.0 1km WNW of Stony Gorge Reservoir, CA
- 1.8 4km NNE of Hamilton City, CA
- 2.0 9km N of Oroville, CA
- 2.5 14km W of Williams, CA
- 1.9 14km S of Hamilton City, 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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.