QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

Earthquake near Hidden Valley Lake, CA

No earthquake was likely felt in Hidden Valley Lake in the 24 hours to 3:24 pm PST (23:24 UTC). The last one was M 2.6, 18 km (11 mi) W, at 4:44 pm PST on 8 November 2026, estimated intensity II (weak) in town. Every earthquake near Hidden Valley Lake

This page: a magnitude 2.1 earthquake was recorded 10 km (6 mi) east-southeast of Hidden Valley Lake, CA, at 10:38 pm PST on 19 February 2020 (06:38 UTC), 9.5 km deep.

USGS: 10km ESE of Hidden Valley Lake, CA

44 km (27 mi) NNE of Santa Rosa, CA · 112 km (69 mi) N of San Francisco, CA

10:38 pm PST, Feb 19, 2020 · · 9.5 km deep · released about 44 lb of TNT

10 km30 km60 km120 km N Napa County 33 kmLake County 44 kmColusa County 47 kmYolo County 48 kmSonoma County 51 kmSutter County 70 kmSolano County 72 kmMarin County 86 kmGlenn County 91 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
10:38 pm PST on 19 February 2020 ()
Where
10 km (6 mi) east-southeast of Hidden Valley Lake, CA · earthquakes near Hidden Valley Lake
Magnitude
M 2.1 (md)
Depth
9.5 km below the surface
Felt
no reports yet
Nearest
Napa County, 33 km SSE
Nearest mapped fault
Hunting Creek-Berryessa fault system, 6 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 2457 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 14 km (9 mi) from the epicentre. In Hidden Valley Lake, 10 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: Middletown, Lower Lake, Angwin, Cobb, Clearlake, Calistoga.

How big was it?

This earthquake released about 44 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 5.8 340,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 240,000× 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 44 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 5.0 on 2016-12-14 — about 22,000 times the energy of this one.

Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.

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 38.7842, -122.4453. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Napa County, CA 33 km (20 mi) SSE earthquakes near Napa County
Lake County, CA 44 km (28 mi) NW earthquakes near Lake County
Colusa County, CA 47 km (29 mi) NNE earthquakes near Colusa County
Yolo County, CA 48 km (30 mi) ESE earthquakes near Yolo County
Sonoma County, CA 51 km (32 mi) SW earthquakes near Sonoma County
Sutter County, CA 70 km (43 mi) ENE earthquakes near Sutter County

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

Aftershocks so far

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

  1. 1.9 3km NNE of The Geysers, CA
  2. 2.0 2km NW of The Geysers, CA
  3. 1.7 1km NW of The Geysers, CA
  4. 1.7 3km SW of Anderson Springs, CA
  5. 1.5 7km NW of The Geysers, CA
  6. 1.9 3km SSW of Anderson Springs, CA
  7. 1.6 6km NW of The Geysers, CA
  8. 1.9 10km SSW of Kelseyville, CA
  9. 1.5 7km NW of The Geysers, CA
  10. 1.5 0km NE of The Geysers, CA
  11. 1.9 2km NW of The Geysers, CA
  12. 1.6 2km NW of The Geysers, CA
  13. 2.0 6km SSW of Yountville, CA
  14. 1.6 8km NW of The Geysers, CA
  15. 1.5 3km NNW of The Geysers, 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.

On USGS

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