230 km W of Ferndale, California

2018-10-02 07:26 UTC · 10 km deep · released about 950 lb of TNT

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: 2018-10-02 07:26 UTC
Magnitude: M 3.0 (ml)
Depth: 10 km below the surface
Felt: no reports yet
Status: Reviewed by a seismologist

USGS · last changed by USGS 2844 days ago · we first saw it 2844 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

How big was it?

This earthquake released about 950 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

Northridge, California 1994 M 6.7 350,000× the energy of this one
Mineral, Virginia 2011 M 5.8 16,000× the energy of this one
Magna, Utah 2020 M 5.7 11,000× the energy of this one
This earthquake M 3.0 about 950 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

Map loads when it scrolls into view

Epicentre 40.5429, -126.9827. Map © OpenStreetMap contributors.

Aftershocks so far

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

4.4 216 km W of Ferndale, California 15:22 UTC
2.7 253 km W of Ferndale, California 06:24 UTC
2.8 236 km W of Ferndale, California 15:03 UTC
2.8 204 km W of Ferndale, California 18:26 UTC
2.5 238 km W of Ferndale, California 19:08 UTC
2.7 262 km W of Ferndale, California 10:11 UTC
4.0 248 km W of Ferndale, California 18:28 UTC
3.2 258 km W of Ferndale, California 01:59 UTC
2.9 off the coast of Northern California 13:37 UTC
3.0 272 km W of Ferndale, California 12:53 UTC
2.8 256 km W of Ferndale, California 01:08 UTC
2.4 214 km W of Ferndale, California 01:35 UTC
2.9 240 km W of Ferndale, California 05:08 UTC
2.7 240 km W of Ferndale, California 04:11 UTC
3.0 203 km W of Ferndale, California 06:45 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 21:49 UTC. 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 5.7 on 2017-09-22 — it released about 11,000 times the energy of this one.

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

On USGS

The official USGS event page — the source of record for every value above
Did you feel it? Report it to USGS — reports go to USGS, not to us
ShakeMap for this event, when USGS has produced one

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