QuakeIndex

Earthquake · reviewed by a seismologist

M 3.2mwr

Earthquake near Detroit Beach, MI

No earthquake was likely felt in Detroit Beach in the 24 hours to 11:52 am EST (16:52 UTC). The last one was M 2.7, 22 km (14 mi) NW, at 5:32 pm EDT on 4 May 2026, estimated intensity III (weak) in town; 222 felt reports to USGS. Every earthquake near Detroit Beach

This page: a magnitude 3.2 earthquake was recorded 2 km (1 mi) south-southeast of Detroit Beach, MI, at 6:55 pm EDT on 21 August 2020 (22:55 UTC), 9.2 km deep. 2,157 people have reported feeling it to USGS.

USGS: 2 km SSE of Detroit Beach, Michigan

55 km (34 mi) SSW of Detroit, MI · 35 km (22 mi) S of Taylor, MI

6:55 pm EDT, Aug 21, 2020 · · 9.2 km deep · released about 1,900 lb of TNT

10 km30 km60 km120 km N Monroe County 14 kmLucas County 28 kmWayne County 42 kmOttawa County 48 kmWashtenaw County 58 kmLenawee County 63 kmSandusky County 64 kmWood County 66 kmFulton County 76 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
6:55 pm EDT on 21 August 2020 ()
Where
2 km (1 mi) south-southeast of Detroit Beach, MI · earthquakes near Detroit Beach
Magnitude
M 3.2 (mwr)
Depth
9.2 km below the surface
Felt
2,157 reports · strongest reported intensity V
Measured shaking
intensity IV (ShakeMap)
Nearest
Monroe County, 14 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1022 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 190 km (118 mi) from the epicentre. In Detroit Beach, 2 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: Woodland Beach, Monroe, South Monroe, West Monroe, Luna Pier, Carleton.

How big was it?

This earthquake released about 1,900 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 180,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 7,900× the energy of this one
  3. Magna, Utah 2020 M 5.7 5,600× the energy of this one
  4. This earthquake M 3.2 about 1,900 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 2× 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

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 41.9125, -83.3179. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Monroe County, MI 14 km (9 mi) W earthquakes near Monroe County
Lucas County, OH 28 km (18 mi) SSW earthquakes near Lucas County
Wayne County, MI 42 km (26 mi) N earthquakes near Wayne County
Ottawa County, OH 48 km (30 mi) SSE earthquakes near Ottawa County
Washtenaw County, MI 58 km (36 mi) NW earthquakes near Washtenaw County
Lenawee County, MI 63 km (39 mi) W earthquakes near Lenawee County

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

Aftershocks so far

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

  1. 2.7 8 km N of Maybee, Michigan
  2. 3.0 7 km SSE of Amherstburg, Canada
  3. 2.3 4 km SSE of Walbridge, Ohio
  4. 2.5 4 km WSW of Millbury, Ohio
  5. 2.6 3 km SSE of Walbridge, Ohio
  6. 2.4 5 km W of Luna Pier, Michigan

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.