QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

Earthquake near Harper, KS

No earthquake was likely felt in Harper in the 24 hours to 3:54 pm CST (21:54 UTC). The last one was M 3.4, 186 km (116 mi) S, at 5:53 am CST on 7 November 2026, estimated intensity II (weak) in town; 23 felt reports to USGS. Every earthquake near Harper

This page: a magnitude 1.8 earthquake was recorded 6 km (4 mi) south of Harper, KS, at 12:28 pm CDT on 15 August 2016 (17:28 UTC), 5.8 km deep.

USGS: 5 km S of Harper, Kansas

79 km (49 mi) SW of Wichita, KS

12:28 pm CDT, Aug 15, 2016 · · 5.8 km deep · released about 13 lb of TNT

10 km30 km60 km120 km N Harper County 6 kmKingman County 37 kmSumner County 47 kmGrant County 54 kmBarber County 58 kmAlfalfa County 62 kmSedgwick County 71 kmPratt County 78 kmReno County 80 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
12:28 pm CDT on 15 August 2016 ()
Where
6 km (4 mi) south of Harper, KS · earthquakes near Harper
Magnitude
M 1.8 (ml)
Depth
5.8 km below the surface
Felt
no reports yet
Nearest
Harper County, 6 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3715 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 13 km (8 mi) from the epicentre. In Harper, 6 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: Anthony 9 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 13 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 1,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 840,000× the energy of this one
  3. Around the size people start to feel M 3.0 75× the energy of this one
  4. This earthquake M 1.8 about 13 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 37.2338, -98.0297. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Harper County, KS 6 km (4 mi) SSW earthquakes near Harper County
Kingman County, KS 37 km (23 mi) NNW earthquakes near Kingman County
Sumner County, KS 47 km (30 mi) E earthquakes near Sumner County
Grant County, OK 54 km (34 mi) SSE earthquakes near Grant County
Barber County, KS 58 km (36 mi) W earthquakes near Barber County
Alfalfa County, OK 62 km (38 mi) SSW earthquakes near Alfalfa 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. 3.3 10 km NW of Harper, Kansas
  2. 1.8 7 km ENE of Caldwell, Kansas
  3. 1.8 10 km ESE of Bluff City, Kansas
  4. 1.9 9 km NNW of Caldwell, Kansas
  5. 2.0 6 km ENE of Caldwell, Kansas
  6. 3.3 7 km NNE of Wakita, Oklahoma
  7. 1.6 6 km ENE of Caldwell, Kansas
  8. 2.7 6 km NNE of Wakita, Oklahoma
  9. 2.7 6 km ENE of Caldwell, Kansas
  10. 2.8 6 km NNE of Wakita, Oklahoma
  11. 3.5 6 km NNE of Wakita, Oklahoma
  12. 3.7 4 km NNW of Wakita, Oklahoma
  13. 3.9 6 km N of Wakita, Oklahoma
  14. 2.4 7 km E of Bluff City, Kansas
  15. 1.5 7 km E of Bluff City, Kansas

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.