QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

Earthquake near Helena, OK

No earthquake was likely felt in Helena in the 24 hours to 4:15 pm CST (22:15 UTC). The last one was M 3.4, 106 km (66 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 Helena

This page: a magnitude 1.6 earthquake was recorded 15 km (10 mi) west-southwest of Helena, OK, at 4:47 pm CDT on 30 June 2023 (21:47 UTC), 7.8 km deep.

USGS: 2 km SE of Aline, Oklahoma

51 km (32 mi) W of Enid, OK · 141 km (87 mi) NW of Oklahoma City, OK

4:47 pm CDT, Jun 30, 2023 · · 7.8 km deep · released about 6.8 lb of TNT

10 km30 km60 km120 km N Major County 22 kmAlfalfa County 28 kmWoods County 47 kmGarfield County 59 kmGrant County 66 kmBlaine County 68 kmKingfisher County 75 kmWoodward County 76 kmDewey County 78 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
4:47 pm CDT on 30 June 2023 ()
Where
15 km (10 mi) west-southwest of Helena, OK · earthquakes near Helena
Oklahoma today
every earthquake in Oklahoma in the last 24 hours
Magnitude
M 1.6 (ml)
Depth
7.8 km below the surface
Felt
no reports yet
Nearest
Major County, 22 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1227 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Helena, 15 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.

Earthquakes near other towns within 30 km: Fairview, Cherokee.

How big was it?

This earthquake released about 6.8 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,600,000× the energy of this one
  3. Around the size people start to feel M 3.0 140× the energy of this one
  4. This earthquake M 1.6 about 6.8 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 200,000 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 36.4915, -98.4280. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Major County, OK 22 km (14 mi) SSW earthquakes near Major County
Alfalfa County, OK 28 km (17 mi) NNE earthquakes near Alfalfa County
Woods County, OK 47 km (29 mi) NW earthquakes near Woods County
Garfield County, OK 59 km (36 mi) ESE earthquakes near Garfield County
Grant County, OK 66 km (41 mi) ENE earthquakes near Grant County
Blaine County, OK 68 km (42 mi) S earthquakes near Blaine County

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

Aftershocks so far

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

  1. 1.7 16 km SSE of Waynoka, Oklahoma
  2. 1.7 4 km N of Nescatunga, Oklahoma
  3. 1.6 3 km SE of Meno, Oklahoma
  4. 2.1 7 km S of Meno, Oklahoma
  5. 1.9 6 km NNW of Ames, Oklahoma
  6. 1.7 3 km NNE of Okeene, Oklahoma
  7. 1.5 3 km NNE of Okeene, Oklahoma
  8. 2.1 3 km NNE of Okeene, Oklahoma
  9. 1.6 3 km N of Okeene, Oklahoma
  10. 1.7 8 km WSW of Waynoka, Oklahoma
  11. 2.3 8 km N of Nash, Oklahoma
  12. 1.5 6 km ENE of Avard, Oklahoma
  13. 1.7 10 km WNW of Dacoma, Oklahoma
  14. 1.8 17 km SE of Waynoka, Oklahoma
  15. 1.9 7 km E of Nescatunga, 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.