QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

Earthquake near Friday Harbor, WA

USGS: 6 km W of Orcas, Washington

45 km (28 mi) WSW of Bellingham, WA · 119 km (74 mi) NNW of Seattle, WA

6:19 am PDT, Jul 11, 2018 · · 15 km deep · released about 5.7 lb of TNT

10 km30 km60 km120 km N San Juan County 11 kmIsland County 55 kmClallam County 83 kmSkagit County 90 kmWhatcom County 92 kmJefferson County 95 kmKitsap County 110 kmSnohomish County 111 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
6:19 am PDT on 11 July 2018 ()
Where
7 km (4 mi) N of Friday Harbor, WA · earthquakes near Friday Harbor
Magnitude
M 1.5 (ml)
Depth
15 km below the surface
Felt
no reports yet
Nearest
San Juan County, 11 km SSW
Nearest mapped fault
Utsalady Point fault, 25 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 3005 days ago

A magnitude 1.5 earthquake was recorded 7 km (4 mi) N of Friday Harbor, WA, at 6:19 am PDT on 11 July 2018 (13:19 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

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 3 earthquakes of M5 or more within 50 km:

  1. 6.0 San Juan Islands, Washington · 21 km NE of this epicentre
  2. 5.5 21 km SSE of Point Roberts, Washington · 23 km N of this epicentre
  3. 5.1 10 km ESE of Salt Spring Island, Canada · 33 km NW 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 48.5925, -123.0302. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Juan County, WA 11 km (7 mi) SSW earthquakes near San Juan County
Island County, WA 55 km (34 mi) SSE earthquakes near Island County
Clallam County, WA 83 km (52 mi) SW earthquakes near Clallam County
Skagit County, WA 90 km (56 mi) E earthquakes near Skagit County
Whatcom County, WA 92 km (57 mi) ENE earthquakes near Whatcom County
Jefferson County, WA 95 km (59 mi) SSW earthquakes near Jefferson County

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

Aftershocks so far

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

  1. 1.8 17 km WNW of Coupeville, Washington
  2. 1.7 10 km SE of Friday Harbor, Washington
  3. 2.2 15 km SSE of Friday Harbor, Washington
  4. 2.2 12 km WNW of Ault Field, Washington
  5. 2.3 12 km NW of Ault Field, Washington
  6. 2.2 12 km WNW of Ault Field, Washington
  7. 1.7 12 km NW of Ault Field, Washington
  8. 1.7 5 km ENE of Anacortes, Washington
  9. 2.1 13 km SW of North Saanich, Canada
  10. 1.8 10 km NE of Port Angeles East, Washington
  11. 1.8 4 km NE of Anacortes, Washington
  12. 2.0 5 km NW of Jamestown, Washington
  13. 2.0 7 km NNW of Friday Harbor, Washington
  14. 1.7 9 km NW of Friday Harbor, Washington
  15. 1.7 10 km SE of Metchosin, Canada

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.