QuakeIndex

Earthquake · reviewed by a seismologist

M 2.6ml

Earthquake near Alva, OK

No earthquake was likely felt in Alva in the 24 hours to 9:25 am CST (15:25 UTC). The last one was M 3.4, 144 km (90 mi) SSE, at 5:53 am CST on 7 November 2026, estimated intensity II (weak) in town; 23 felt reports to USGS. Every earthquake near Alva

This page: a magnitude 2.6 earthquake was recorded 32 km (20 mi) east-northeast of Alva, OK, at 9:42 am CST on 9 November 2017 (15:42 UTC), 4.3 km deep. 2 people have reported feeling it to USGS.

USGS: 3 km WNW of Byron, Oklahoma

9:42 am CST, Nov 9, 2017 · · 4.3 km deep · released about 240 lb of TNT

Every earthquake near Alva Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Alfalfa County 20 kmHarper County 38 kmBarber County 47 kmGrant County 50 kmWoods County 52 kmMajor County 69 kmKingman County 73 kmGarfield County 77 kmSumner County 82 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
9:42 am CST on 9 November 2017 ()
Where
32 km (20 mi) east-northeast of Alva, OK · earthquakes near Alva
Oklahoma today
every earthquake in Oklahoma in the last 24 hours
Magnitude
M 2.6 (ml)
Depth
4.3 km below the surface
Felt
2 reports · strongest reported intensity II
Nearest
Alfalfa County, 20 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3207 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 51 km (32 mi) from the epicentre. In Alva, 32 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: Cherokee 18 km, intensity III · Alva 32 km, intensity II · Anthony 38 km, intensity II · Helena 41 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 240 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 63,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 45,000× the energy of this one
  3. Around the size people start to feel M 3.0 4× the energy of this one
  4. This earthquake M 2.6 about 240 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 36.9137, -98.3301. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Alfalfa County, OK 20 km (13 mi) S earthquakes near Alfalfa County
Harper County, KS 38 km (24 mi) NE earthquakes near Harper County
Barber County, KS 47 km (29 mi) NW earthquakes near Barber County
Grant County, OK 50 km (31 mi) ESE earthquakes near Grant County
Woods County, OK 52 km (32 mi) WSW earthquakes near Woods County
Major County, OK 69 km (43 mi) SSW earthquakes near Major County

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

Aftershocks so far

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

  1. 2.6 14 km WNW of Alva, Oklahoma
  2. 1.6 6 km SE of Anthony, Kansas
  3. 2.7 11 km SW of Wakita, Oklahoma
  4. 1.7 6 km S of Freeport, Kansas
  5. 1.8 4 km NW of Bluff City, Kansas
  6. 1.7 1 km SW of Anthony, Kansas
  7. 1.7 6 km NNE of Bluff City, Kansas
  8. 2.6 4 km NNE of Cherokee, Oklahoma
  9. 1.9 5 km WSW of Freeport, Kansas
  10. 2.5 0 km W of Wakita, Oklahoma
  11. 1.7 5 km SSW of Bluff City, Kansas
  12. 1.5 9 km W of Bluff City, Kansas
  13. 2.6 4 km SSE of Manchester, Oklahoma
  14. 1.7 6 km NNE of Bluff City, Kansas
  15. 2.5 2 km SW of Cherokee, Oklahoma

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.