QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8mb_lg

Earthquake near Alva, OK

No earthquake was likely felt in Alva in the 24 hours to 7:37 am CST (13:37 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 2.8 earthquake was recorded 24 km (15 mi) southeast of Alva, OK, at 4:20 am CST on 2 March 2019 (10:20 UTC), 5.0 km deep. 4 people have reported feeling it to USGS.

USGS: 4 km WSW of Lambert, Oklahoma

4:20 am CST, Mar 2, 2019 · · 5.0 km deep · released about 480 lb of TNT

10 km30 km60 km120 km N Alfalfa County 15 kmWoods County 36 kmMajor County 39 kmGrant County 62 kmBarber County 65 kmGarfield County 68 kmHarper County 68 kmWoodward County 77 kmBlaine 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
4:20 am CST on 2 March 2019 ()
Where
24 km (15 mi) southeast of Alva, OK · earthquakes near Alva
Oklahoma today
every earthquake in Oklahoma in the last 24 hours
Magnitude
M 2.8 (mb_lg)
Depth
5.0 km below the surface
Felt
4 reports · strongest reported intensity III
Nearest
Alfalfa County, 15 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2738 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 62 km (39 mi) from the epicentre. In Alva, 24 km away, the estimate is intensity III (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 14 km, intensity III · Helena 22 km, intensity III · Alva 24 km, intensity III · Fairview 44 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 480 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 32,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 22,000× the energy of this one
  3. Around the size people start to feel M 3.0 2× the energy of this one
  4. This earthquake M 2.8 about 480 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

The largest earthquake within 50 km since 2016 was M 5.1 on 2016-02-13 — about 2,800 times the energy of this one.

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 36.6611, -98.4647. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Alfalfa County, OK 15 km (9 mi) ENE earthquakes near Alfalfa County
Woods County, OK 36 km (23 mi) WNW earthquakes near Woods County
Major County, OK 39 km (24 mi) S earthquakes near Major County
Grant County, OK 62 km (38 mi) ENE earthquakes near Grant County
Barber County, KS 65 km (41 mi) NNW earthquakes near Barber County
Garfield County, OK 68 km (42 mi) ESE earthquakes near Garfield County

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

Aftershocks so far

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

  1. 2.1 7 km SW of Avard, Oklahoma
  2. 1.8 10 km ESE of Lambert, Oklahoma
  3. 2.1 10 km ESE of Lambert, Oklahoma
  4. 2.3 7 km ENE of Nescatunga, Oklahoma
  5. 2.2 7 km ENE of Nescatunga, Oklahoma
  6. 2.6 10 km ESE of Lambert, Oklahoma
  7. 2.5 4 km SE of Cleo Springs, Oklahoma
  8. 2.3 9 km NE of Quinlan, Oklahoma
  9. 2.3 8 km W of Fairview, Oklahoma
  10. 1.7 1 km SE of Meno, Oklahoma
  11. 1.5 Oklahoma
  12. 2.2 7 km E of Nescatunga, Oklahoma
  13. 1.6 7 km E of Nescatunga, Oklahoma
  14. 1.7 13 km SSE of Waynoka, Oklahoma
  15. 2.3 5 km NNW of Ames, 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.