Earthquake · reviewed by a seismologist
M 1.2ml
Earthquake near Mirrormont, WA
USGS: 4 km ENE of Mirrormont, Washington
35 km (22 mi) ESE of Seattle, WA · 16 km (10 mi) SSE of Sammamish, WA
- When
- 6:27 pm PDT on 29 September 2026 ()
- Where
- 5 km (3 mi) ENE of Mirrormont, WA · earthquakes near Mirrormont
- Magnitude
- M 1.2 (ml)
- Depth
- 19 km below the surface
- Felt
- no reports yet
- Nearest
- King County, 8 km ENE
- Nearest mapped fault
- Seattle fault, 6 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 2 days ago
A magnitude 1.2 earthquake was recorded 5 km (3 mi) ENE of Mirrormont, WA, at 6:27 pm PDT on 29 September 2026 (01:27 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.
Earthquakes near other towns within 30 km: Hobart, Issaquah, Snoqualmie, Fall City, North Bend, Maple Valley.
How big was it?
This earthquake released about 2.2 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.2 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 6,900,000× the energy of this one
- Magna, Utah 2020 M 5.7 4,900,000× the energy of this one
- Around the size people start to feel M 3.0 440× the energy of this one
- This earthquake M 1.2 about 2.2 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 4.6 on 2019-07-12 — about 100,000 times the energy of this one.
Before 2016, the USGS record lists 4 earthquakes of M5 or more within 50 km:
- 6.7 1 km ENE of Dash Point, Washington · 39 km WSW of this epicentre
- 5.4 8 km NNE of Lake Marcel-Stillwater, Washington · 32 km N of this epicentre
- 5.2 9 km NE of Lake Marcel-Stillwater, Washington · 32 km NNE of this epicentre
- 5.0 3 km WSW of Des Moines, Washington · 34 km WSW 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 47.4720, -121.9342. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| King County, WA | 8 km (5 mi) | ENE | earthquakes near King County |
| Pierce County, WA | 50 km (31 mi) | SSW | earthquakes near Pierce County |
| Kitsap County, WA | 57 km (35 mi) | WNW | earthquakes near Kitsap County |
| Snohomish County, WA | 66 km (41 mi) | N | earthquakes near Snohomish County |
| Thurston County, WA | 90 km (56 mi) | SW | earthquakes near Thurston County |
| Island County, WA | 94 km (58 mi) | NW | earthquakes near Island County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
2 earthquakes have been recorded within 50 km since this one.
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.