QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5md

Earthquake near Klamath Falls, OR

No earthquake was likely felt in Klamath Falls in the 24 hours to 5:57 am PST (13:57 UTC). The last one was M 1.9, 10 km (7 mi) NNW, at 1:58 pm PDT on 13 August 2026, estimated intensity II (weak) in town. Every earthquake near Klamath Falls

This page: a magnitude 2.5 earthquake was recorded 36 km (23 mi) south-southwest of Klamath Falls, OR, at 5:42 pm PDT on 6 November 2021 (00:42 UTC), 7.5 km deep.

USGS: 6km SW of Dorris, CA

5:42 pm PDT, Nov 6, 2021 · · 7.5 km deep · released about 170 lb of TNT

Every earthquake near Klamath Falls Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Siskiyou County 61 kmJackson County 80 kmKlamath County 88 kmModoc County 109 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
5:42 pm PDT on 6 November 2021 ()
Where
36 km (23 mi) south-southwest of Klamath Falls, OR · earthquakes near Klamath Falls
Magnitude
M 2.5 (md)
Depth
7.5 km below the surface
Felt
no reports yet
Nearest
Siskiyou County, 61 km SW
Nearest mapped fault
Cedar Mountain fault system, 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 1763 days ago

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 21 km (13 mi) from the epicentre. In Klamath Falls, 36 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.

How big was it?

This earthquake released about 170 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 89,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 63,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.6× the energy of this one
  4. This earthquake M 2.5 about 170 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:

  1. 6.0 27 km WNW of Klamath Falls, Oregon · 49 km N of this epicentre
  2. 5.9 22 km WNW of Klamath Falls, Oregon · 44 km N of this epicentre
  3. 5.1 20 km WNW of Klamath Falls, Oregon · 41 km N 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 41.9255, -121.9590. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Siskiyou County, CA 61 km (38 mi) SW earthquakes near Siskiyou County
Jackson County, OR 80 km (50 mi) NW earthquakes near Jackson County
Klamath County, OR 88 km (55 mi) NNE earthquakes near Klamath County
Modoc County, CA 109 km (68 mi) ESE earthquakes near Modoc County

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

Aftershocks so far

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

  1. 1.0 18 km WNW of Klamath Falls, Oregon
  2. 1.9 10 km NNW of Klamath Falls, Oregon
  3. 2.1 5 km SSW of Merrill, Oregon
  4. 1.8 31 km E of Tennant, CA
  5. 2.0 11 km NNW of Klamath Falls, Oregon
  6. 2.0 26 km ENE of Hornbrook, CA
  7. 1.6 11 km NNW of Klamath Falls, Oregon
  8. 2.2 5 km W of Merrill, Oregon
  9. 1.9 24 km E of Tennant, CA
  10. 2.6 23 km WSW of Mount Hebron, CA
  11. 1.6 23 km WSW of Klamath Falls, Oregon
  12. 2.1 4 km SW of Tennant, CA
  13. 1.6 4 km SW of Tennant, CA
  14. 1.6 25 km WNW of Klamath Falls, Oregon
  15. 1.8 16 km ESE of Dorris, California

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.