Earthquake · reviewed by a seismologist
M 1.5md
Earthquake near Brooktrails, CA
No earthquake was likely felt in Brooktrails in the 24 hours to 10:46 am PST (18:46 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 1.5 earthquake was recorded 7 km (4 mi) northeast of Brooktrails, CA, at 2:56 am PDT on 6 May 2023 (09:56 UTC), 4.8 km deep.
USGS: 7km NE of Brooktrails, CA
- When
- 2:56 am PDT on 6 May 2023 ()
- Where
- 7 km (4 mi) northeast of Brooktrails, CA · earthquakes near Brooktrails
- Magnitude
- M 1.5 (md)
- Depth
- 4.8 km below the surface
- Felt
- no reports yet
- Nearest
- Mendocino County, 11 km WSW
- 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 1286 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 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 9 km (6 mi) from the epicentre. In Brooktrails, 7 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: Brooktrails 7 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 5.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 2,800,000× the energy of this one
- Magna, Utah 2020 M 5.7 2,000,000× the energy of this one
- Around the size people start to feel M 3.0 180× the energy of this one
- This earthquake M 1.5 about 5.4 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 240,000 times the energy of this one.
Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:
- 5.9 9 km S of Leggett, California · 47 km NW of this epicentre
- 5.2 6 km ESE of Talmage, California · 46 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 39.4888, -123.3317. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Mendocino County, CA | 11 km (7 mi) | WSW | earthquakes near Mendocino County |
| Lake County, CA | 66 km (41 mi) | SE | earthquakes near Lake County |
| Glenn County, CA | 81 km (50 mi) | E | earthquakes near Glenn County |
| Colusa County, CA | 100 km (62 mi) | ESE | earthquakes near Colusa County |
| Sonoma County, CA | 113 km (70 mi) | SSE | earthquakes near Sonoma County |
| Tehama County, CA | 118 km (73 mi) | NE | earthquakes near Tehama County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
54 earthquakes have been recorded within 50 km since this one.
- 1.6 15 km ENE of Brooktrails, CA
- 1.8 8 km N of Lake Pillsbury, CA
- 1.8 23 km E of Navarro Head, CA
- 2.1 5 km ESE of Willits, CA
- 2.1 6 km ESE of Lake Pillsbury, CA
- 1.8 15 km NW of Lake Pillsbury, CA
- 1.6 15 km WNW of Lake Pillsbury, CA
- 1.6 17 km ESE of Lake Pillsbury, CA
- 1.8 16 km NW of Brooktrails, CA
- 1.5 13 km NNE of Laytonville, CA
- 1.6 10 km SE of Lake Pillsbury, CA
- 2.2 10 km N of Lake Pillsbury, CA
- 2.6 10 km N of Lake Pillsbury, CA
- 1.8 6 km ESE of Lake Pillsbury, CA
- 1.7 14 km N of Lake Pillsbury, 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.