QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Red Bluff, CA

No earthquake was likely felt in Red Bluff in the 24 hours to 6:38 am PST (14:38 UTC). The last one was M 4.0, 97 km (60 mi) SW, at 5:01 am PDT on 28 October 2026, estimated intensity II (weak) in town; 14 felt reports to USGS. Every earthquake near Red Bluff

This page: a magnitude 1.8 earthquake was recorded 6 km (4 mi) east-southeast of Red Bluff, CA, at 8:34 am PST on 8 November 2018 (16:34 UTC), 26 km deep.

USGS: 6km ESE of Red Bluff, CA

53 km (33 mi) NW of Chico, CA · 49 km (31 mi) SSE of Redding, CA

8:34 am PST, Nov 8, 2018 · · 26 km deep · released about 15 lb of TNT

10 km30 km60 km120 km N Tehama County 6 kmGlenn County 64 kmShasta County 69 kmButte County 73 kmTrinity County 97 kmColusa County 109 kmPlumas County 116 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
8:34 am PST on 8 November 2018 ()
Where
6 km (4 mi) east-southeast of Red Bluff, CA · earthquakes near Red Bluff
Magnitude
M 1.8 (md)
Depth
26 km below the surface
Felt
no reports yet
Nearest
Tehama County, 6 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2924 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 Red Bluff, 6 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: Gerber, Los Molinos, Rancho Tehama Reserve, Corning.

How big was it?

This earthquake released about 15 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 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 730,000× the energy of this one
  3. Around the size people start to feel M 3.0 65× the energy of this one
  4. This earthquake M 1.8 about 15 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 one earthquake of M5 or more within 50 km:

  1. 5.5 33 km NW of Rancho Tehama Reserve, California · 46 km W 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 40.1528, -122.1768. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Tehama County, CA 6 km (3 mi) WSW earthquakes near Tehama County
Glenn County, CA 64 km (40 mi) SSW earthquakes near Glenn County
Shasta County, CA 69 km (43 mi) N earthquakes near Shasta County
Butte County, CA 73 km (45 mi) SE earthquakes near Butte County
Trinity County, CA 97 km (60 mi) NW earthquakes near Trinity County
Colusa County, CA 109 km (67 mi) S earthquakes near Colusa County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

51 earthquakes have been recorded within 50 km since this one.

  1. 2.0 5km NNE of Hamilton City, CA
  2. 1.5 11km SSW of Manton, CA
  3. 2.2 18km W of Manton, CA
  4. 1.7 12km SSW of Manton, CA
  5. 2.8 4km NE of Hamilton City, CA
  6. 1.8 4km NE of Hamilton City, CA
  7. 2.9 4km NE of Hamilton City, CA
  8. 1.8 18km ESE of Anderson, CA
  9. 1.9 6km N of Chico, CA
  10. 1.6 18km ESE of Anderson, CA
  11. 1.7 16km ESE of Anderson, CA
  12. 2.9 13km SSW of Manton, CA
  13. 1.6 18km SSW of Mineral, CA
  14. 1.6 20km NE of Red Bluff, CA
  15. 1.8 20km NE of Red Bluff, 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.