Earthquake · reviewed by a seismologist
M 2.3ml
Earthquake near Black Diamond, WA
No earthquake was likely felt in Black Diamond in the 24 hours to 7:22 pm PST (03:22 UTC). The last one was M 4.2, 55 km (34 mi) W, at 2:05 pm PDT on 29 September 2026, estimated intensity II (weak) in town; 9,329 felt reports to USGS. Every earthquake near Black Diamond
This page: a magnitude 2.3 earthquake was recorded 5 km (3 mi) southeast of Black Diamond, WA, at 1:02 pm PDT on 18 March 2021 (20:02 UTC), 13 km deep. 3 people have reported feeling it to USGS.
USGS: 4 km SE of Black Diamond, Washington
48 km (30 mi) SE of Seattle, WA · 19 km (12 mi) E of Auburn, WA
- When
- 1:02 pm PDT on 18 March 2021 ()
- Where
- 5 km (3 mi) southeast of Black Diamond, WA · earthquakes near Black Diamond
- Magnitude
- M 2.3 (ml)
- Depth
- 13 km below the surface
- Felt
- 3 reports · strongest reported intensity II
- Nearest
- King County, 26 km NNE
- Nearest mapped fault
- Tacoma fault, 15 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 1996 days ago
Earthquake alerts for Black Diamond, WA
Get a notification in this browser when USGS records an earthquake near Black Diamond, 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 14 km (9 mi) from the epicentre. In Black Diamond, 5 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: Enumclaw 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 72 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 210,000× the energy of this one
- Magna, Utah 2020 M 5.7 150,000× the energy of this one
- Around the size people start to feel M 3.0 13× the energy of this one
- This earthquake M 2.3 about 72 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 2 earthquakes of M5 or more within 50 km:
- 6.7 1 km ENE of Dash Point, Washington · 34 km W of this epicentre
- 5.0 3 km WSW of Des Moines, Washington · 33 km WNW 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 47.2747, -121.9658. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| King County, WA | 26 km (16 mi) | NNE | earthquakes near King County |
| Pierce County, WA | 29 km (18 mi) | SSW | earthquakes near Pierce County |
| Kitsap County, WA | 66 km (41 mi) | NW | earthquakes near Kitsap County |
| Thurston County, WA | 75 km (47 mi) | WSW | earthquakes near Thurston County |
| Lewis County, WA | 83 km (52 mi) | SSW | earthquakes near Lewis County |
| Snohomish County, WA | 88 km (55 mi) | N | earthquakes near Snohomish County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
55 earthquakes have been recorded within 50 km since this one.
- 1.5 1 km E of Ames Lake, Washington
- 1.5 11 km ESE of Enumclaw, Washington
- 1.5 3 km NNE of White Center, Washington
- 1.7 6 km NE of Snoqualmie, Washington
- 1.7 5 km SW of Fall City, Washington
- 1.7 3 km E of Carnation, Washington
- 1.6 8 km NE of Tanner, Washington
- 2.3 14 km NNE of Ashford, Washington
- 1.8 14 km NNE of Ashford, Washington
- 1.8 2 km NE of Mirrormont, Washington
- 1.5 1 km SSW of Ravensdale, Washington
- 1.5 4 km SSE of Carbonado, Washington
- 1.5 4 km SSE of Carbonado, Washington
- 2.2 9 km NNE of Snoqualmie, Washington
- 1.9 13 km ESE of Enumclaw, 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.