QuakeIndex

quarry blast · reviewed by a seismologist

M 1.8ml

Earthquake near Ponderay, ID

USGS: 5 km NNW of Ponderay, Idaho

2:14 pm PDT, Apr 19, 2017 · · -2.0 km deep · released about 14 lb of TNT

10 km30 km60 km120 km N Bonner County 7 kmBoundary County 46 kmPend Oreille County 54 kmKootenai County 76 kmLincoln County 83 kmStevens County 96 kmSpokane County 103 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
2:14 pm PDT on 19 April 2017 ()
Where
6 km (4 mi) NNW of Ponderay, ID · earthquakes near Ponderay
Magnitude
M 1.8 (ml)
Depth
-2.0 km below the surface
Felt
no reports yet
Nearest
Bonner County, 7 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3452 days ago

A magnitude 1.8 earthquake was recorded 6 km (4 mi) NNW of Ponderay, ID, at 2:14 pm PDT on 19 April 2017 (21:14 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: Sandpoint.

USGS catalogues this as quarry blast, not an earthquake.

How big was it?

This earthquake released about 14 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 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 790,000× the energy of this one
  3. Around the size people start to feel M 3.0 70× the energy of this one
  4. This earthquake M 1.8 about 14 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 48.3568, -116.5532. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Bonner County, ID 7 km (4 mi) WSW earthquakes near Bonner County
Boundary County, ID 46 km (29 mi) N earthquakes near Boundary County
Pend Oreille County, WA 54 km (34 mi) WNW earthquakes near Pend Oreille County
Kootenai County, ID 76 km (48 mi) S earthquakes near Kootenai County
Lincoln County, MT 83 km (52 mi) ENE earthquakes near Lincoln County
Stevens County, WA 96 km (60 mi) W earthquakes near Stevens County

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

Aftershocks so far

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

  1. 2.3 2 km NE of Dover, Idaho
  2. 2.2 8 km WNW of Dover, Idaho
  3. 1.6 13 km NNW of Athol, Idaho
  4. 1.9 6 km NNW of Priest River, Idaho
  5. 2.1 12 km NNW of Kootenai, Idaho
  6. 1.6 11 km NNW of Kootenai, Idaho
  7. 2.1 7 km WSW of Clark Fork, Idaho
  8. 1.6 18 km N of Kootenai, Idaho
  9. 2.2 8 km NW of Ponderay, Idaho
  10. 1.8 13 km SSW of East Hope, Idaho
  11. 2.1 8 km WNW of Dover, Idaho
  12. 1.8 9 km NNW of Ponderay, Idaho
  13. 1.5 11 km SSW of East Hope, Idaho
  14. 2.5 10 km SSW of East Hope, Idaho
  15. 2.6 7 km W of Clark Fork, Idaho

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.