QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near Lakeport, CA

No earthquake was likely felt in Lakeport in the 24 hours to 10:44 pm PST (06:44 UTC). The last one was M 4.0, 51 km (32 mi) N, at 5:01 am PDT on 28 October 2026, estimated intensity II (weak) in town; 14 felt reports to USGS. Every earthquake near Lakeport

This page: a magnitude 1.6 earthquake was recorded 13 km (8 mi) west-southwest of Lakeport, CA, at 5:59 pm PDT on 20 June 2018 (00:59 UTC), 2.0 km deep.

USGS: 13km WSW of Lakeport, CA

5:59 pm PDT, Jun 20, 2018 · · 2.0 km deep · released about 6.4 lb of TNT

10 km30 km60 km120 km N Lake County 30 kmSonoma County 56 kmMendocino County 57 kmColusa County 74 kmNapa County 86 kmGlenn County 87 kmYolo County 107 kmMarin County 111 kmSutter County 118 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
5:59 pm PDT on 20 June 2018 ()
Where
13 km (8 mi) west-southwest of Lakeport, CA · earthquakes near Lakeport
Magnitude
M 1.6 (md)
Depth
2.0 km below the surface
Felt
no reports yet
Nearest
Lake County, 30 km ENE
Nearest mapped fault
Maacama fault, 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 3060 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 10 km (6 mi) from the epicentre. In Lakeport, 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: Talmage, North Lakeport, Ukiah, Kelseyville, Upper Lake, Nice.

How big was it?

This earthquake released about 6.4 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 2,400,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,700,000× the energy of this one
  3. Around the size people start to feel M 3.0 150× the energy of this one
  4. This earthquake M 1.6 about 6.4 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 200,000 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 · 12 km NNW 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 39.0153, -123.0663. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lake County, CA 30 km (18 mi) ENE earthquakes near Lake County
Sonoma County, CA 56 km (35 mi) SSE earthquakes near Sonoma County
Mendocino County, CA 57 km (35 mi) NW earthquakes near Mendocino County
Colusa County, CA 74 km (46 mi) ENE earthquakes near Colusa County
Napa County, CA 86 km (53 mi) SE earthquakes near Napa County
Glenn County, CA 87 km (54 mi) NE earthquakes near Glenn County

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

Aftershocks so far

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

  1. 1.9 7km NW of The Geysers, CA
  2. 1.8 7km NW of The Geysers, CA
  3. 1.6 7km NW of The Geysers, CA
  4. 2.1 7km NW of The Geysers, CA
  5. 1.6 1km NNW of The Geysers, CA
  6. 1.8 5km NW of Cobb, CA
  7. 1.6 13km NW of The Geysers, CA
  8. 1.6 6km NW of The Geysers, CA
  9. 1.7 7km NW of The Geysers, CA
  10. 1.7 3km SW of Anderson Springs, CA
  11. 1.7 6km WNW of Cobb, CA
  12. 1.6 7km NW of The Geysers, CA
  13. 2.0 7km NW of The Geysers, CA
  14. 1.6 8km NW of The Geysers, CA
  15. 1.7 19km NNW of Cloverdale, 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.