QuakeIndex

Earthquake · reviewed by a seismologist

M 3.6mwr

Earthquake near Broken Bow, NE

No earthquake was likely felt in Broken Bow in the 24 hours to 7:24 am CST (13:24 UTC). The last one was M 5.0, 622 km (387 mi) S, at 5:21 am CDT on 23 July 2026, estimated intensity II (weak) in town; 499 felt reports to USGS. Every earthquake near Broken Bow

This page: a magnitude 3.6 earthquake was recorded 40 km (25 mi) west of Broken Bow, NE, at 12:09 am CDT on 26 July 2018 (05:09 UTC), 1.2 km deep. 8 people have reported feeling it to USGS.

USGS: 7 km SE of Arnold, Nebraska

12:09 am CDT, Jul 26, 2018 · · 1.2 km deep · released about 3.8 tons of TNT

10 km30 km60 km120 km N Logan County 32 kmCuster County 33 kmBlaine County 62 kmThomas County 62 kmDawson County 63 kmLincoln County 64 kmLoup County 77 kmMcPherson County 88 kmValley County 97 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
12:09 am CDT on 26 July 2018 ()
Where
40 km (25 mi) west of Broken Bow, NE · earthquakes near Broken Bow
Magnitude
M 3.6 (mwr)
Depth
1.2 km below the surface
Felt
8 reports · strongest reported intensity IV
Measured shaking
intensity IV (ShakeMap)
Nearest
Logan County, 32 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 886 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 339 km (211 mi) from the epicentre. In Broken Bow, 40 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: Broken Bow 40 km, intensity III. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 3.8 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.6 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 45,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 2,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,400× the energy of this one
  4. This earthquake M 3.6 about 3.8 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 7.9× 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 4.1 on 2018-06-30 — about 5.6 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 41.3812, -100.1229. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Logan County, NE 32 km (20 mi) NW earthquakes near Logan County
Custer County, NE 33 km (21 mi) E earthquakes near Custer County
Blaine County, NE 62 km (39 mi) N earthquakes near Blaine County
Thomas County, NE 62 km (39 mi) NNW earthquakes near Thomas County
Dawson County, NE 63 km (39 mi) SSE earthquakes near Dawson County
Lincoln County, NE 64 km (40 mi) SW earthquakes near Lincoln County

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

Aftershocks so far

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

  1. 3.0 10 km S of Arnold, Nebraska
  2. 2.1 5 km S of Arnold, Nebraska
  3. 2.6 8 km SE of Arnold, Nebraska
  4. 2.5 13 km WNW of Callaway, Nebraska
  5. 2.6 7 km WSW of Arnold, Nebraska
  6. 2.6 6 km SE of Arnold, Nebraska
  7. 2.7 4 km E of Arnold, Nebraska

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.