QuakeIndex

explosion · reviewed by a seismologist

M 1.8ml

Earthquake near Republic, WA

No earthquake was likely felt in Republic in the 24 hours to 8:51 am PST (16:51 UTC). The last one was M 1.9, 8 km (5 mi) ESE, at 2:25 pm PDT on 17 August 2020, estimated intensity II (weak) in town. Every earthquake near Republic

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.8 explosion was recorded 49 km (30 mi) north-northeast of Republic, WA, at 11:54 am PDT on 12 August 2016 (18:54 UTC), less than 1 km deep.

USGS: 11 km NW of Danville, Washington

11:54 am PDT, Aug 12, 2016 · · -0.6 km deep · released about 16 lb of TNT

10 km30 km60 km120 km N Ferry County 67 kmStevens County 94 kmOkanogan County 102 kmPend Oreille County 116 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
11:54 am PDT on 12 August 2016 ()
Where
49 km (30 mi) north-northeast of Republic, WA · earthquakes near Republic
Magnitude
M 1.8 (ml)
Depth
-0.6 km below the surface
Felt
no reports yet
Nearest
Ferry County, 67 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3740 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 14 km (9 mi) from the epicentre. In Republic, 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.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 16 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 5.8 970,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 680,000× the energy of this one
  3. Around the size people start to feel M 3.0 61× the energy of this one
  4. This earthquake M 1.8 about 16 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 49.0763, -118.5958. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Ferry County, WA 67 km (42 mi) S earthquakes near Ferry County
Stevens County, WA 94 km (58 mi) SE earthquakes near Stevens County
Okanogan County, WA 102 km (64 mi) SW earthquakes near Okanogan County
Pend Oreille County, WA 116 km (72 mi) ESE earthquakes near Pend Oreille County

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

Aftershocks so far

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

  1. 1.9 17 km NNE of Grand Forks, Canada
  2. 1.7 12 km WNW of Danville, Washington
  3. 1.7 16 km NW of Grand Forks, Canada
  4. 1.7 24 km ENE of Oroville, Washington
  5. 2.0 35 km N of Grand Forks, Canada
  6. 2.2 25 km ENE of Oroville, Washington
  7. 2.1 6 km ESE of Grand Forks, Canada
  8. 1.9 35 km NE of Osoyoos, Canada
  9. 2.2 21 km WNW of Malo, 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.