QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

Earthquake near Issaquah, WA

Yes. A magnitude 1.8 earthquake was recorded 49 km (30 mi) ESE of Issaquah, WA, at 12:38 am PDT on 30 July 2017 (07:38 UTC), 12 km deep. 5 people have reported feeling it to USGS.

This was on 30 July 2017. The latest near Issaquah: M 2.5 on 26 June 2026.

USGS: 11 km SSW of Snoqualmie Pass, Washington

74 km (46 mi) ESE of Seattle, WA · 53 km (33 mi) SE of Sammamish, WA

12:38 am PDT, Jul 30, 2017 · · 12 km deep · released about 14 lb of TNT

Every earthquake near Issaquah Felt it? Tell USGS Check my area
10 km30 km60 km120 km N King County 34 kmPierce County 58 kmKittitas County 64 kmSnohomish County 86 kmChelan County 89 kmKitsap County 96 kmLewis County 106 kmYakima County 110 kmThurston County 110 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
12:38 am PDT on 30 July 2017 ()
Where
49 km (30 mi) ESE of Issaquah, WA · earthquakes near Issaquah
Magnitude
M 1.8 (ml)
Depth
12 km below the surface
Felt
5 reports · strongest reported intensity III
Nearest
King County, 34 km NW
Nearest mapped fault
Rattlesnake Mountain fault, 23 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 3282 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 5 km (3 mi) from the epicentre. In Issaquah, 49 km away, the estimate is intensity I (not felt). 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: Wilderness Rim, Riverbend, Tanner.

How big was it?

This earthquake released about 14 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 760,000× the energy of this one
  3. Around the size people start to feel M 3.0 68× the energy of this one
  4. This earthquake M 1.8 about 14 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 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 47.3053, -121.4782. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
King County, WA 34 km (21 mi) NW earthquakes near King County
Pierce County, WA 58 km (36 mi) WSW earthquakes near Pierce County
Kittitas County, WA 64 km (40 mi) ESE earthquakes near Kittitas County
Snohomish County, WA 86 km (53 mi) NNW earthquakes near Snohomish County
Chelan County, WA 89 km (55 mi) NE earthquakes near Chelan County
Kitsap County, WA 96 km (59 mi) WNW earthquakes near Kitsap County

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

Aftershocks so far

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

  1. 1.6 4 km SE of Ames Lake, Washington
  2. 1.6 12 km NNE of Tanner, Washington
  3. 1.9 1 km NE of Tanner, Washington
  4. 1.7 9 km SE of Enumclaw, Washington
  5. 1.6 10 km ESE of Enumclaw, Washington
  6. 1.9 11 km ESE of Enumclaw, Washington
  7. 1.6 13 km S of Snoqualmie Pass, Washington
  8. 1.6 11 km W of Greenwater, Washington
  9. 1.7 8 km SSW of Wilderness Rim, Washington
  10. 2.6 8 km SSW of Wilderness Rim, Washington
  11. 2.0 10 km ENE of Fall City, Washington
  12. 1.8 13 km ESE of Enumclaw, Washington
  13. 1.7 11 km ESE of Enumclaw, Washington
  14. 2.0 11 km ENE of Enumclaw, Washington
  15. 1.8 14 km S of Snoqualmie Pass, Washington

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.