18 km NNE of Upper Lake, California

2016-09-12 18:40 UTC · 9.2 km deep · released about 46 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: 2016-09-12 18:40 UTC
Magnitude: M 2.1 (md)
Depth: 9.2 km below the surface
Felt: 2 reports · strongest reported intensity II
Nearest: Lake County, 24 km SSE
Status: Reviewed by a seismologist

USGS · last changed by USGS 3515 days ago · we first saw it 3515 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 2 people have reported feeling it to USGS.

How big was it?

This earthquake released about 46 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.

Mineral, Virginia 2011 M 5.8 330,000× the energy of this one
Magna, Utah 2020 M 5.7 230,000× the energy of this one
Around the size people start to feel M 3.0 21× the energy of this one
This earthquake M 2.1 about 46 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 39.3140, -122.8162. Map © OpenStreetMap contributors.

Nearby places

Place	Distance	Direction
Lake County, CA	24 km (15 mi)	NNW of here	earthquakes near Lake County
Glenn County, CA	48 km (30 mi)	SW of here	earthquakes near Glenn County
Colusa County, CA	52 km (32 mi)	WNW of here	earthquakes near Colusa County
Mendocino County, CA	55 km (34 mi)	ESE of here	earthquakes near Mendocino County
Sonoma County, CA	88 km (55 mi)	N of here	earthquakes near Sonoma County
Napa County, CA	99 km (62 mi)	NNW of here	earthquakes near Napa County

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

Aftershocks so far

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

1.9 20 km NNE of Upper Lake, California 23:02 UTC
1.8 19 km NNE of Upper Lake, California 05:08 UTC
1.7 8 km NE of Boonville, California 06:11 UTC
2.8 20 km NNE of Upper Lake, California 20:03 UTC
1.7 9 km NNE of Hopland, California 13:38 UTC
2.0 Northern California 17:51 UTC
1.5 20 km NNE of Upper Lake, California 01:36 UTC
1.8 17 km NE of Willits, California 19:30 UTC
1.5 18 km NE of Upper Lake, California 08:04 UTC
2.1 6 km N of Hopland, California 13:42 UTC
1.6 19 km NNE of Upper Lake, California 16:14 UTC
1.5 20 km NNE of Upper Lake, California 16:06 UTC
1.6 21 km E of Potter Valley, California 14:21 UTC
1.8 10 km SSW of Kelseyville, California 05:03 UTC
1.7 18 km NE of Upper Lake, California 13:18 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 08:11 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 5.1 on 2016-08-10 — it released about 29,000 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.