9km W of Williams, CA

2020-03-09 03:57 UTC · 17 km deep · released about 14 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: 2020-03-09 03:57 UTC
Magnitude: M 1.8 (md)
Depth: 17 km below the surface
Felt: no reports yet
Nearest: Colusa County, 2 km NE
Status: Reviewed by a seismologist

USGS · last changed by USGS 2392 days ago · we first saw it 2392 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 14 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
Magna, Utah 2020 M 5.7 790,000× the energy of this one
Around the size people start to feel M 3.0 70× the energy of this one
This earthquake M 1.8 about 14 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 39.1635, -122.2543. Map © OpenStreetMap contributors.

Nearby places

Place	Distance	Direction
Colusa County, CA	2 km (1 mi)	SW of here	earthquakes near Colusa County
Lake County, CA	43 km (27 mi)	E of here	earthquakes near Lake County
Sutter County, CA	50 km (31 mi)	WNW of here	earthquakes near Sutter County
Glenn County, CA	50 km (31 mi)	SSE of here	earthquakes near Glenn County
Yolo County, CA	62 km (38 mi)	NNW of here	earthquakes near Yolo County
Napa County, CA	73 km (46 mi)	N of here	earthquakes near Napa County

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

Aftershocks so far

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

1.7 10km ENE of Clearlake, CA 20:50 UTC
1.5 9km E of Clearlake Oaks, CA 01:49 UTC
1.9 8km E of Clearlake Oaks, CA 15:53 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 13:07 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

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.