QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

16km ENE of Hydesville, CA

· 23 km deep · released about 43 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Humboldt County 14 kmTrinity County 67 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 2.1 (md)
Depth
23 km below the surface
Felt
no reports yet
Nearest
Humboldt County, 14 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2550 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 43 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 350,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 250,000× the energy of this one
  3. Around the size people start to feel M 3.0 22× the energy of this one
  4. This earthquake M 2.1 about 43 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 40.5808, -123.9083. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Humboldt County, CA 14 km (9 mi) S of here earthquakes near Humboldt County
Trinity County, CA 67 km (42 mi) W of here earthquakes near Trinity County
Siskiyou County, CA 161 km (100 mi) SW of here earthquakes near Siskiyou County

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

Aftershocks so far

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

  1. 1.5 7km WSW of Petrolia, CA
  2. 1.6 3km SW of Petrolia, CA
  3. 1.7 7km WSW of Petrolia, CA
  4. 2.1 6km WSW of Petrolia, CA
  5. 2.6 3km WNW of Hydesville, CA
  6. 1.6 5km WSW of Petrolia, CA
  7. 3.1 3km NW of Redway, CA
  8. 2.2 20km SE of Rio Dell, CA
  9. 1.7 5km NE of Petrolia, CA
  10. 2.9 20km SE of Rio Dell, CA
  11. 1.8 19km SE of Rio Dell, CA
  12. 1.5 13km SE of Petrolia, CA
  13. 2.2 18km NW of Petrolia, CA
  14. 2.5 8km SW of McKinleyville, CA
  15. 2.0 15km SE of Petrolia, 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 5.6 on 2019-06-23 — it released about 170,000 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.