QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near North Lakeport, CA

No earthquake was likely felt in North Lakeport in the 24 hours to 3:24 pm PST (23:24 UTC). The last one was M 1.8, 12 km (8 mi) NW, at 10:36 am PST on 5 November 2026, estimated intensity II (weak) in town. Every earthquake near North Lakeport

This page: a magnitude 1.6 earthquake was recorded 7 km (4 mi) west-northwest of North Lakeport, CA, at 10:53 am PDT on 15 July 2017 (17:53 UTC), 7.8 km deep.

USGS: 6 km WNW of North Lakeport, California

10:53 am PDT, Jul 15, 2017 · · 7.8 km deep · released about 7.8 lb of TNT

10 km30 km60 km120 km N Lake County 20 kmMendocino County 53 kmColusa County 64 kmSonoma County 66 kmGlenn County 73 kmNapa County 88 kmYolo County 105 kmSutter County 110 kmMarin County 120 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
10:53 am PDT on 15 July 2017 ()
Where
7 km (4 mi) west-northwest of North Lakeport, CA · earthquakes near North Lakeport
Magnitude
M 1.6 (md)
Depth
7.8 km below the surface
Felt
no reports yet
Nearest
Lake County, 20 km E
Nearest mapped fault
Big Valley fault, 8 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 3396 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 8 km (5 mi) from the epicentre. In North Lakeport, 7 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.

Likely felt in: Upper Lake 8 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 7.8 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,400,000× the energy of this one
  3. Around the size people start to feel M 3.0 120× the energy of this one
  4. This earthquake M 1.6 about 7.8 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 170,000 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 · 10 km W 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 39.1142, -122.9772. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lake County, CA 20 km (12 mi) E earthquakes near Lake County
Mendocino County, CA 53 km (33 mi) NW earthquakes near Mendocino County
Colusa County, CA 64 km (40 mi) E earthquakes near Colusa County
Sonoma County, CA 66 km (41 mi) S earthquakes near Sonoma County
Glenn County, CA 73 km (46 mi) NE earthquakes near Glenn County
Napa County, CA 88 km (55 mi) SE earthquakes near Napa County

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

Aftershocks so far

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

  1. 1.5 10km NW of The Geysers, CA
  2. 1.7 6km WNW of The Geysers, CA
  3. 1.5 2km NW of The Geysers, CA
  4. 2.6 4km SW of Anderson Springs, CA
  5. 1.6 7 km ENE of Hopland, California
  6. 1.8 6 km W of Cobb, California
  7. 1.9 18 km NE of Upper Lake, California
  8. 2.0 7 km S of Cobb, California
  9. 1.5 3km WNW of Cobb, CA
  10. 2.0 5km SW of Anderson Springs, CA
  11. 2.9 9 km S of Cobb, California
  12. 1.7 7km NW of The Geysers, CA
  13. 1.5 7km WNW of The Geysers, CA
  14. 1.5 1km NNE of The Geysers, CA
  15. 1.7 3km W of Cobb, 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.