Earthquake · reviewed by a seismologist
M 1.8md
Earthquake near Willits, CA
No earthquake was likely felt in Willits in the 24 hours to 3:23 am PST (11:23 UTC). The last one was M 1.5, 9 km (5 mi) ESE, at 10:30 pm PST on 2 November 2026, estimated intensity II (weak) in town. Every earthquake near Willits
This page: a magnitude 1.8 earthquake was recorded 9 km (6 mi) east-southeast of Willits, CA, at 11:25 pm PST on 10 December 2020 (07:25 UTC), 4.8 km deep. 1 person has reported feeling it to USGS.
USGS: 9km ESE of Willits, CA
- When
- 11:25 pm PST on 10 December 2020 ()
- Where
- 9 km (6 mi) east-southeast of Willits, CA · earthquakes near Willits
- Magnitude
- M 1.8 (md)
- Depth
- 4.8 km below the surface
- Felt
- 1 report · strongest reported intensity III
- Nearest
- Mendocino County, 17 km WNW
- Nearest mapped fault
- Maacama fault, 4 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 2155 days ago
Earthquake alerts for Willits, CA
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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, people at rest would likely notice it out to about 13 km (8 mi) from the epicentre. In Willits, 9 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: Willits 9 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 17 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 5.8 870,000× the energy of this one
- Magna, Utah 2020 M 5.7 620,000× the energy of this one
- Around the size people start to feel M 3.0 55× the energy of this one
- This earthquake M 1.8 about 17 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 5.1 on 2016-08-10 — about 75,000 times the energy of this one.
Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:
- 5.2 6 km ESE of Talmage, California · 32 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 39.3695, -123.2607. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Mendocino County, CA | 17 km (11 mi) | WNW | earthquakes near Mendocino County |
| Lake County, CA | 53 km (33 mi) | ESE | earthquakes near Lake County |
| Glenn County, CA | 78 km (49 mi) | ENE | earthquakes near Glenn County |
| Colusa County, CA | 91 km (56 mi) | ESE | earthquakes near Colusa County |
| Sonoma County, CA | 98 km (61 mi) | SSE | earthquakes near Sonoma County |
| Tehama County, CA | 122 km (76 mi) | NE | 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 5km SSW of Redwood Valley, CA
- 1.7 7km SW of Boonville, CA
- 1.6 5km ENE of Laytonville, CA
- 2.5 14km NNW of Brooktrails, CA
- 1.6 5km N of Lake Pillsbury, CA
- 1.7 12km W of Lakeport, CA
- 1.5 21km ENE of Navarro Head, CA
- 1.9 10km ESE of Redwood Valley, CA
- 2.0 6km ENE of Lake Pillsbury, CA
- 1.7 11km N of Lake Pillsbury, CA
- 2.6 10km ESE of Redwood Valley, CA
- 1.8 10km NNW of Redwood Valley, CA
- 2.2 11km ESE of Willits, CA
- 2.0 9km ESE of Redwood Valley, CA
- 1.8 9km ESE of Redwood 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
- 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.