Earthquake · reviewed by a seismologist
M 2.9md
Earthquake near Brooktrails, CA
No earthquake was likely felt in Brooktrails in the 24 hours to 7:37 am PST (15:37 UTC). The last one was M 4.0, 38 km (23 mi) E, at 5:01 am PDT on 28 October 2026, estimated intensity III (weak) in town; 14 felt reports to USGS. Every earthquake near Brooktrails
This page: a magnitude 2.9 earthquake was recorded 11 km (7 mi) north of Brooktrails, CA, at 12:08 pm PDT on 7 July 2023 (19:08 UTC), 7.3 km deep. 22 people have reported feeling it to USGS.
USGS: 11km N of Brooktrails, CA
- When
- 12:08 pm PDT on 7 July 2023 ()
- Where
- 11 km (7 mi) north of Brooktrails, CA · earthquakes near Brooktrails
- Magnitude
- M 2.9 (md)
- Depth
- 7.3 km below the surface
- Felt
- 22 reports · strongest reported intensity III
- Nearest
- Mendocino County, 14 km SSW
- Nearest mapped fault
- Maacama fault, 5 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 1160 days ago
Earthquake alerts for Brooktrails, CA
Get a notification in this browser when USGS records an earthquake near Brooktrails, 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 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 31 km (19 mi) from the epicentre. In Brooktrails, 11 km away, the estimate is intensity III (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: Brooktrails 11 km, intensity III · Willits 15 km, intensity III · Laytonville 19 km, intensity II · Covelo 30 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 680 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.
- Mineral, Virginia 2011 M 5.8 22,000× the energy of this one
- Magna, Utah 2020 M 5.7 16,000× the energy of this one
- Around the size people start to feel M 3.0 1.4× the energy of this one
- This earthquake M 2.9 about 680 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 4.3 on 2019-04-29 — about 130 times the energy of this one.
Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:
- 5.9 9 km S of Leggett, California · 41 km NW 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 39.5413, -123.3642. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Mendocino County, CA | 14 km (9 mi) | SSW | earthquakes near Mendocino County |
| Lake County, CA | 72 km (45 mi) | SE | earthquakes near Lake County |
| Glenn County, CA | 83 km (51 mi) | E | earthquakes near Glenn County |
| Colusa County, CA | 105 km (65 mi) | ESE | earthquakes near Colusa County |
| Tehama County, CA | 116 km (72 mi) | NE | earthquakes near Tehama County |
| Sonoma County, CA | 119 km (74 mi) | SSE | earthquakes near Sonoma County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
56 earthquakes have been recorded within 50 km since this one.
- 1.9 16 km ESE of Navarro Head, CA
- 2.0 7 km ESE of Willits, CA
- 2.2 9 km NNE of Rockport, CA
- 1.5 5 km N of Redwood Valley, CA
- 1.6 14 km NW of Laytonville, CA
- 2.3 14 km NW of Laytonville, CA
- 1.5 13 km NNE of Brooktrails, CA
- 1.9 2 km NW of Redwood Valley, CA
- 1.5 8 km SE of Willits, CA
- 2.3 6 km W of Laytonville, CA
- 1.7 16 km N of Covelo, CA
- 1.7 16 km N of Covelo, CA
- 1.7 7 km WSW of Laytonville, CA
- 1.6 5 km NW of Lake Pillsbury, CA
- 1.9 13 km SSE of Laytonville, 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.