QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5md

Earthquake near Yountville, CA

No earthquake was likely felt in Yountville in the 24 hours to 2:14 am PST (10:14 UTC). The last one was M 2.4, 19 km (12 mi) SSE, at 10:47 am PDT on 6 October 2026, estimated intensity II (weak) in town; 1 felt report to USGS. Every earthquake near Yountville

This page: a magnitude 1.5 earthquake was recorded 13 km (8 mi) northeast of Yountville, CA, at 12:00 pm PDT on 28 June 2020 (19:00 UTC), 7.5 km deep.

USGS: 12km NE of Yountville, CA

78 km (49 mi) N of San Francisco, CA · 20 km (12 mi) NNE of Napa, CA

12:00 pm PDT, Jun 28, 2020 · · 7.5 km deep · released about 5.7 lb of TNT

10 km30 km60 km120 km N Napa County 8 kmSolano County 35 kmYolo County 38 kmSonoma County 59 kmMarin County 64 kmContra Costa County 67 kmColusa County 78 kmSutter County 79 kmSacramento County 79 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
12:00 pm PDT on 28 June 2020 ()
Where
13 km (8 mi) northeast of Yountville, CA · earthquakes near Yountville
Magnitude
M 1.5 (md)
Depth
7.5 km below the surface
Felt
no reports yet
Nearest
Napa County, 8 km WNW
Nearest mapped fault
Green Valley fault, under 1 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 2325 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 7 km (4 mi) from the epicentre. In Yountville, 13 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: Saint Helena, Napa, Deer Park, Angwin, Winters, Green Valley.

How big was it?

This earthquake released about 5.7 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,900,000× the energy of this one
  3. Around the size people start to feel M 3.0 170× the energy of this one
  4. This earthquake M 1.5 about 5.7 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 6.0 The 2014 South Napa, California Earthquake · 29 km S of this epicentre
  2. 5.4 South of Elmira, California · 36 km ESE 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 38.4720, -122.2485. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Napa County, CA 8 km (5 mi) WNW earthquakes near Napa County
Solano County, CA 35 km (22 mi) SE earthquakes near Solano County
Yolo County, CA 38 km (24 mi) NE earthquakes near Yolo County
Sonoma County, CA 59 km (37 mi) W earthquakes near Sonoma County
Marin County, CA 64 km (40 mi) SW earthquakes near Marin County
Contra Costa County, CA 67 km (41 mi) SSE earthquakes near Contra Costa County

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

Aftershocks so far

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

  1. 1.6 15km ENE of Yountville, CA
  2. 1.9 13km ENE of Yountville, CA
  3. 2.1 6km SW of Calistoga, CA
  4. 1.9 7km WSW of Kenwood, CA
  5. 1.9 11km ENE of Healdsburg, CA
  6. 1.6 5km E of Vallejo, CA
  7. 2.5 6km W of Yountville, CA
  8. 1.6 3km SSW of Anderson Springs, CA
  9. 1.9 3km S of Anderson Springs, CA
  10. 2.0 7km WSW of Kenwood, CA
  11. 2.0 3km SW of American Canyon, CA
  12. 1.5 11km ESE of Hidden Valley Lake, CA
  13. 1.9 10km ESE of Hidden Valley Lake, CA
  14. 1.5 12km E of Yountville, CA
  15. 1.6 12km E of Angwin, 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.