explosion · reviewed by a seismologist
M 1.6ml
Earthquake near Hobart, WA
No earthquake was likely felt in Hobart in the 24 hours to 12:24 pm PST (20:24 UTC). The last one was M 2.6, 11 km (7 mi) E, at 6:09 pm PDT on 14 October 2026, estimated intensity II (weak) in town; 46 felt reports to USGS. Every earthquake near Hobart
No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.6 explosion was recorded 7 km (4 mi) east-southeast of Hobart, WA, at 10:20 am PDT on 4 May 2018 (17:20 UTC), less than 1 km deep.
USGS: 6 km ESE of Hobart, Washington
42 km (26 mi) SE of Seattle, WA · 24 km (15 mi) SSE of Sammamish, WA
- When
- 10:20 am PDT on 4 May 2018 ()
- Where
- 7 km (4 mi) east-southeast of Hobart, WA · earthquakes near Hobart
- Magnitude
- M 1.6 (ml)
- Depth
- -1.3 km below the surface
- Felt
- no reports yet
- Nearest
- King County, 11 km NNE
- Nearest mapped fault
- Rattlesnake Mountain fault, 4 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 3115 days ago
Earthquake alerts for Hobart, WA
Get a notification in this browser when USGS records an earthquake near Hobart, WA. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
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 11 km (7 mi) from the epicentre. In Hobart, 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.
Earthquakes near other towns within 30 km: Ravensdale, Wilderness Rim, Mirrormont, Maple Valley, Riverbend, North Bend.
USGS catalogues this as explosion, not an earthquake.
How big was it?
This earthquake released about 6.6 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.
- Mineral, Virginia 2011 M 5.8 2,300,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,600,000× the energy of this one
- Around the size people start to feel M 3.0 140× the energy of this one
- This earthquake M 1.6 about 6.6 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 4 earthquakes of M5 or more within 50 km:
- 6.7 1 km ENE of Dash Point, Washington · 40 km WSW of this epicentre
- 5.4 8 km NNE of Lake Marcel-Stillwater, Washington · 40 km N of this epicentre
- 5.2 9 km NE of Lake Marcel-Stillwater, Washington · 39 km N of this epicentre
- 5.0 3 km WSW of Des Moines, Washington · 36 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 47.4030, -121.8897. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| King County, WA | 11 km (7 mi) | NNE | earthquakes near King County |
| Pierce County, WA | 44 km (27 mi) | SSW | earthquakes near Pierce County |
| Kitsap County, WA | 63 km (39 mi) | WNW | earthquakes near Kitsap County |
| Snohomish County, WA | 73 km (45 mi) | N | earthquakes near Snohomish County |
| Thurston County, WA | 88 km (55 mi) | SW | earthquakes near Thurston County |
| Kittitas County, WA | 97 km (60 mi) | ESE | earthquakes near Kittitas County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
48 earthquakes have been recorded within 50 km since this one.
- 2.1 4 km ENE of Lake Marcel-Stillwater, Washington
- 1.6 12 km NNE of Tanner, Washington
- 1.9 1 km NE of Tanner, Washington
- 1.7 9 km SE of Enumclaw, Washington
- 1.6 10 km ESE of Enumclaw, Washington
- 2.3 0 km ESE of Riverton, Washington
- 1.9 11 km ESE of Enumclaw, Washington
- 1.6 4 km WSW of Monroe, Washington
- 1.9 0 km SE of Normandy Park, Washington
- 1.8 1 km NE of Normandy Park, Washington
- 1.6 0 km E of Normandy Park, Washington
- 1.6 13 km S of Snoqualmie Pass, Washington
- 1.6 3 km W of Federal Way, Washington
- 1.6 11 km W of Greenwater, Washington
- 1.7 8 km SSW of Wilderness Rim, 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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.