Earthquake near Union Hill-Novelty Hill, WA

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 15 km (9 mi) from the epicentre. In Union Hill-Novelty Hill, 3 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: Sammamish 8 km, intensity II · City of Sammamish 9 km, intensity II · Redmond 10 km, intensity II · West Lake Sammamish 14 km, intensity II · Fall City 14 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 23 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 660,000× the energy of this one
2. Magna, Utah 2020 M 5.7 470,000× the energy of this one
3. Around the size people start to feel M 3.0 42× the energy of this one
4. This earthquake M 1.9 about 23 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 9,800 times the energy of this one.

Before 2016, the USGS record lists 4 earthquakes of M5 or more within 50 km:

1. 5.4 8 km NNE of Lake Marcel-Stillwater, Washington · 13 km NE of this epicentre May 3, 1996
2. 5.2 9 km NE of Lake Marcel-Stillwater, Washington · 15 km NE of this epicentre Jul 18, 1932
3. 5.0 4 km ENE of Machias, Washington · 36 km N of this epicentre May 15, 1954
4. 5.0 3 km WSW of Des Moines, Washington · 43 km SW of this epicentre Jan 29, 1995

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 47.6750, -121.9912. Map © OpenStreetMap contributors.

Nearby places

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

Aftershocks so far

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

1. 2.3 6 km WSW of Shoreline, Washington 19:12 UTC
2. 2.8 2 km SW of Wilderness Rim, Washington 01:00 UTC
3. 1.7 8 km ENE of Snoqualmie, Washington 16:35 UTC
4. 1.6 2 km NE of Esperance, Washington 06:20 UTC
5. 1.7 Puget Sound region, Washington 04:18 UTC
6. 1.9 1 km ENE of Granite Falls, Washington 19:42 UTC
7. 1.7 4 km NNW of White Center, Washington 04:50 UTC
8. 1.9 2 km SSW of Esperance, Washington 13:04 UTC
9. 1.6 2 km ESE of Wilderness Rim, Washington 05:25 UTC
10. 1.5 12 km ESE of Riverbend, Washington 01:13 UTC
11. 1.7 1 km ENE of Granite Falls, Washington 22:44 UTC
12. 1.6 2 km NNE of Woods Creek, Washington 21:18 UTC
13. 1.5 Washington 07:50 UTC
14. 1.9 1 km NNW of Des Moines, Washington 13:28 UTC
15. 2.0 Puget Sound region, Washington 11:55 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 08:40 UTC. 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.