QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

Earthquake near Amboy, WA

USGS: 11 km NW of Amboy, Washington

51 km (32 mi) N of Portland, OR · 40 km (25 mi) N of Vancouver, WA

7:04 pm PDT, Jul 17, 2018 · · 15 km deep · released about 6.2 lb of TNT

10 km30 km60 km120 km N Clark County 25 kmCowlitz County 25 kmColumbia County 42 kmSkamania County 46 kmMultnomah County 50 kmWashington County 65 kmLewis County 67 kmWahkiakum County 76 kmHood River County 87 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
7:04 pm PDT on 17 July 2018 ()
Where
12 km (7 mi) NW of Amboy, WA · earthquakes near Amboy
Magnitude
M 1.5 (ml)
Depth
15 km below the surface
Felt
no reports yet
Nearest
Clark County, 25 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2999 days ago

A magnitude 1.5 earthquake was recorded 12 km (7 mi) NW of Amboy, WA, at 7:04 pm PDT on 17 July 2018 (02:04 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: La Center, Yacolt, Woodland, Lewisville, Columbia City, Battle Ground.

How big was it?

This earthquake released about 6.2 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,700,000× the energy of this one
  3. Around the size people start to feel M 3.0 150× the energy of this one
  4. This earthquake M 1.5 about 6.2 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 17 earthquakes of M5 or more within 50 km; the five largest:

  1. 5.7 38 km NNE of Amboy, Washington · 36 km NE of this epicentre
  2. 5.2 5 km E of Bridgeton, Oregon · 44 km S of this epicentre
  3. 5.2 37 km NNE of Amboy, Washington · 36 km NE of this epicentre
  4. 5.2 23 km S of Morton, Washington · 46 km NNE of this epicentre
  5. 5.1 28 km ENE of Amboy, Washington · 33 km E 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 45.9910, -122.5420. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Clark County, WA 25 km (15 mi) S earthquakes near Clark County
Cowlitz County, WA 25 km (16 mi) NNW earthquakes near Cowlitz County
Columbia County, OR 42 km (26 mi) W earthquakes near Columbia County
Skamania County, WA 46 km (28 mi) E earthquakes near Skamania County
Multnomah County, OR 50 km (31 mi) S earthquakes near Multnomah County
Washington County, OR 65 km (40 mi) SW earthquakes near Washington 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. 1.8 0 km SW of Kalama, Washington
  2. 1.6 1 km SSW of Cherry Grove, Washington
  3. 1.8 23 km SSE of Mossyrock, Washington
  4. 1.5 4 km NW of North Portland, Oregon
  5. 1.8 24 km N of Amboy, Washington
  6. 1.8 23 km SSE of Mossyrock, Washington
  7. 1.8 23 km SSE of Mossyrock, Washington
  8. 1.9 6 km NNW of West Longview, Washington
  9. 1.5 Washington-Oregon border region
  10. 1.8 12 km NNW of Amboy, Washington
  11. 1.7 11 km WNW of Warren, Oregon
  12. 2.0 8 km S of Scappoose, Oregon
  13. 1.6 20 km NE of Kalama, Washington
  14. 1.6 8 km E of Kalama, Washington
  15. 2.1 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.