QuakeIndex

mining explosion · reviewed by a seismologist

M 3.0ml

Earthquake near Grand Rapids, MN

No earthquake was likely felt in Grand Rapids in the 24 hours to 5:52 am CST (11:52 UTC). The last one was M 3.3, 128 km (79 mi) ENE, at 10:41 am CDT on 30 April 2026, estimated intensity II (weak) in town. Every earthquake near Grand Rapids

No: USGS classifies this as a mining explosion, not an earthquake. A magnitude 3.0 mining explosion was recorded 19 km (12 mi) east-southeast of Grand Rapids, MN, at 12:27 pm CDT on 19 May 2021 (17:27 UTC), less than 1 km deep.

USGS: 7 km N of Warba, Minnesota

12:27 pm CDT, May 19, 2021 · · 0.0 km deep · released about 950 lb of TNT

10 km30 km60 km120 km N Itasca County 41 kmAitkin County 67 kmSt. Louis County 72 kmCarlton County 81 kmCass County 84 kmCrow Wing County 99 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
12:27 pm CDT on 19 May 2021 ()
Where
19 km (12 mi) east-southeast of Grand Rapids, MN · earthquakes near Grand Rapids
Magnitude
M 3.0 (ml)
Depth
0.0 km below the surface
Felt
no reports yet
Nearest
Itasca County, 41 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1937 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 73 km (45 mi) from the epicentre. In Grand Rapids, 19 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.

Earthquakes near other towns within 30 km: Coleraine, Cohasset, Keewatin.

USGS catalogues this as mining explosion, not an earthquake.

How big was it?

This earthquake released about 950 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 350,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 16,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 11,000× the energy of this one
  4. This earthquake M 3.0 about 950 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 47.1966, -93.2823. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Itasca County, MN 41 km (25 mi) NW earthquakes near Itasca County
Aitkin County, MN 67 km (42 mi) S earthquakes near Aitkin County
St. Louis County, MN 72 km (45 mi) NE earthquakes near St. Louis County
Carlton County, MN 81 km (50 mi) SE earthquakes near Carlton County
Cass County, MN 84 km (52 mi) WSW earthquakes near Cass County
Crow Wing County, MN 99 km (61 mi) SW earthquakes near Crow Wing County

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

Aftershocks so far

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

  1. 2.9 7 km S of Buhl, Minnesota
  2. 3.0 3 km N of Chisholm, Minnesota
  3. 3.1 5 km NW of Hibbing, Minnesota
  4. 3.2 3 km NW of Buhl, Minnesota

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.