QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

Earthquake near Upper Lake, CA

No earthquake was likely felt in Upper Lake in the 24 hours to 12:28 pm PST (20:28 UTC). The last one was M 1.6, 8 km (5 mi) W, at 4:31 am PST on 10 November 2026, estimated intensity II (weak) in town. Every earthquake near Upper Lake

This page: a magnitude 2.1 earthquake was recorded 22 km (13 mi) north-northeast of Upper Lake, CA, at 9:45 pm PDT on 19 September 2016 (04:45 UTC), 12 km deep. 1 person has reported feeling it to USGS.

USGS: 21 km NNE of Upper Lake, California

9:45 pm PDT, Sep 19, 2016 · · 12 km deep · released about 43 lb of TNT

Every earthquake near Upper Lake Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lake County 26 kmGlenn County 45 kmColusa County 51 kmMendocino County 57 kmSonoma County 91 kmSutter County 100 kmTehama County 100 kmNapa County 101 kmYolo County 106 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
9:45 pm PDT on 19 September 2016 ()
Where
22 km (13 mi) north-northeast of Upper Lake, CA · earthquakes near Upper Lake
Magnitude
M 2.1 (md)
Depth
12 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Lake County, 26 km S
Nearest mapped fault
Bartlett Springs fault system, 5 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3561 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 12 km (7 mi) from the epicentre. In Upper Lake, 22 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Earthquakes near other towns within 30 km: Nice, North Lakeport.

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.

For this area

The largest earthquake within 50 km since 2016 was M 5.1 on 2016-08-10 — about 31,000 times the energy of this one.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.2 6 km ESE of Talmage, California · 36 km SW of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 39.3368, -122.7923. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lake County, CA 26 km (16 mi) S earthquakes near Lake County
Glenn County, CA 45 km (28 mi) NE earthquakes near Glenn County
Colusa County, CA 51 km (32 mi) ESE earthquakes near Colusa County
Mendocino County, CA 57 km (35 mi) W earthquakes near Mendocino County
Sonoma County, CA 91 km (57 mi) S earthquakes near Sonoma County
Sutter County, CA 100 km (62 mi) ESE earthquakes near Sutter County

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

Aftershocks so far

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

  1. 2.4 7 km NNE of Hopland, California
  2. 2.4 7 km NNE of Hopland, California
  3. 2.1 19 km NNE of Upper Lake, California
  4. 1.7 21 km NNE of Upper Lake, California
  5. 3.1 20 km NNE of Upper Lake, California
  6. 1.9 7 km NNE of Hopland, California
  7. 1.5 6 km SSE of Talmage, California
  8. 1.6 20 km WSW of Stonyford, California
  9. 1.9 20 km NNE of Upper Lake, California
  10. 1.8 19 km NNE of Upper Lake, California
  11. 2.8 20 km NNE of Upper Lake, California
  12. 1.7 9 km NNE of Hopland, California
  13. 2.0 Northern California
  14. 1.5 20 km NNE of Upper Lake, California
  15. 1.8 17 km NE of Willits, California

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.

On USGS

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