QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

Earthquake near Helena, OK

No earthquake was likely felt in Helena in the 24 hours to 10:09 am CST (16:09 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 3.1 earthquake was recorded 8 km (5 mi) west-southwest of Helena, OK, at 2:06 am CDT on 19 October 2016 (07:06 UTC), 6.6 km deep.

USGS: 8 km WSW of Helena, Oklahoma

45 km (28 mi) WNW of Enid, OK · 140 km (87 mi) NNW of Oklahoma City, OK

2:06 am CDT, Oct 19, 2016 · · 6.6 km deep · released about 1,300 lb of TNT

Every earthquake near Helena Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Alfalfa County 23 kmMajor County 29 kmWoods County 51 kmGarfield County 53 kmGrant County 59 kmBlaine County 72 kmKingfisher County 74 kmHarper County 78 kmWoodward County 83 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
2:06 am CDT on 19 October 2016 ()
Where
8 km (5 mi) west-southwest of Helena, OK · earthquakes near Helena
Oklahoma today
every earthquake in Oklahoma in the last 24 hours
Magnitude
M 3.1 (ml)
Depth
6.6 km below the surface
Felt
no reports yet
Nearest
Alfalfa County, 23 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3588 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 128 km (80 mi) from the epicentre. In Helena, 8 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: Helena 8 km, intensity III · Cherokee 26 km, intensity III · Fairview 30 km, intensity III · Alva 42 km, intensity III · Enid 45 km, intensity III · Okeene 45 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 250,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,900× the energy of this one
  4. This earthquake M 3.1 about 1,300 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.4× more

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 1,000 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 36.5225, -98.3547. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Alfalfa County, OK 23 km (14 mi) N earthquakes near Alfalfa County
Major County, OK 29 km (18 mi) SW earthquakes near Major County
Woods County, OK 51 km (32 mi) WNW earthquakes near Woods County
Garfield County, OK 53 km (33 mi) ESE earthquakes near Garfield County
Grant County, OK 59 km (36 mi) ENE earthquakes near Grant County
Blaine County, OK 72 km (45 mi) S earthquakes near Blaine County

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

Aftershocks so far

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

  1. 2.9 17 km SE of Waynoka, Oklahoma
  2. 2.5 12 km WSW of Cleo Springs, Oklahoma
  3. 2.7 16 km SE of Waynoka, Oklahoma
  4. 2.7 5 km N of Lambert, Oklahoma
  5. 2.6 16 km SSE of Waynoka, Oklahoma
  6. 3.0 17 km SSE of Waynoka, Oklahoma
  7. 2.6 17 km SSE of Waynoka, Oklahoma
  8. 3.0 17 km SSE of Waynoka, Oklahoma
  9. 2.9 17 km SSE of Waynoka, Oklahoma
  10. 2.9 17 km SSE of Waynoka, Oklahoma
  11. 2.5 4 km NNE of Lambert, Oklahoma
  12. 2.6 4 km NNE of Cherokee, Oklahoma
  13. 2.5 16 km SSE of Waynoka, Oklahoma
  14. 3.0 16 km SSE of Waynoka, Oklahoma
  15. 2.5 6 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.