QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

14km E of Rockport, CA

· -0.7 km deep · released about 11 lb of TNT

10 km30 km60 km120 km N Mendocino County 37 kmLake County 104 kmGlenn County 108 kmHumboldt County 112 kmTrinity 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
-0.7 km below the surface
Felt
no reports yet
Nearest
Mendocino County, 37 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1488 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 11 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 1,300,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 930,000× the energy of this one
  3. Around the size people start to feel M 3.0 83× the energy of this one
  4. This earthquake M 1.7 about 11 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 39.7203, -123.6560. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 37 km (23 mi) NNW of here earthquakes near Mendocino County
Lake County, CA 104 km (64 mi) NW of here earthquakes near Lake County
Glenn County, CA 108 km (67 mi) W of here earthquakes near Glenn County
Humboldt County, CA 112 km (70 mi) SSE of here earthquakes near Humboldt County
Trinity County, CA 113 km (70 mi) SSW of here earthquakes near Trinity County

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

Aftershocks so far

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

  1. 1.6 16km ENE of Brooktrails, CA
  2. 1.5 11km NNE of Brooktrails, CA
  3. 1.8 8km ESE of Redway, CA
  4. 1.7 20km NNE of Rockport, CA
  5. 1.9 11km W of Laytonville, CA
  6. 2.5 5km E of Covelo, CA
  7. 1.7 19km NNW of Laytonville, CA
  8. 1.5 16km NNW of Laytonville, CA
  9. 1.9 8km ENE of Brooktrails, CA
  10. 1.9 5km E of Covelo, CA
  11. 1.8 4km E of Covelo, CA
  12. 1.5 4km SW of Brooktrails, CA
  13. 1.7 12km N of Brooktrails, CA
  14. 1.5 8km NE of Brooktrails, CA
  15. 1.8 8km NE of Brooktrails, 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 4.3 on 2017-12-14 — it released about 6,500 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.