QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

29 km WSW of Hayfork, CA

· 23 km deep · released about 12 lb of TNT

10 km30 km60 km120 km N Trinity County 40 kmHumboldt County 47 kmMendocino County 112 kmTehama County 113 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
Magnitude
M 1.7 (md)
Depth
23 km below the surface
Felt
no reports yet
Nearest
Trinity County, 40 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 26 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 12 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 870,000× the energy of this one
  3. Around the size people start to feel M 3.0 78× the energy of this one
  4. This earthquake M 1.7 about 12 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.

Where

Epicentre 40.4387, -123.4957. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Trinity County, CA 40 km (25 mi) SW of here earthquakes near Trinity County
Humboldt County, CA 47 km (29 mi) SE of here earthquakes near Humboldt County
Mendocino County, CA 112 km (70 mi) N of here earthquakes near Mendocino County
Tehama County, CA 113 km (70 mi) WNW of here earthquakes near Tehama County
Glenn County, CA 132 km (82 mi) NW of here earthquakes near Glenn County

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

Aftershocks so far

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

  1. 2.2 32 km NE of Redway, CA
  2. 1.7 10 km SE of Rio Dell, CA
  3. 1.7 16 km NNW of Redway, CA
  4. 1.8 3 km SE of Redway, CA
  5. 1.7 29 km N of Redway, CA
  6. 1.9 36 km E of Hydesville, CA
  7. 2.6 7 km E of Hydesville, CA
  8. 2.0 12 km NW of Hayfork, CA
  9. 1.6 4 km ESE of Redway, CA
  10. 3.7 36 km E of Hydesville, CA
  11. 1.9 16 km SSE of Willow Creek, CA
  12. 1.6 2 km ENE of Redway, CA
  13. 1.8 1 km N of Redway, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 5.3 on 2023-01-01 — it released about 260,000 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.