QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

1 km NE of Spencerville, Maryland

· 6.2 km deep · released about 15 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Howard County 15 kmMontgomery County 21 kmDistrict of Columbia 25 kmArlington County 30 kmFalls Church city 32 kmPrince George's County 34 kmAlexandria city 36 kmBaltimore city 36 kmAnne Arundel County 38 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
Magnitude
M 1.8 (ml)
Depth
6.2 km below the surface
Felt
83 reports · strongest reported intensity III
Nearest
Howard County, 15 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 752 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 83 people have reported feeling it to USGS.

How big was it?

This earthquake released about 15 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× the energy of this one
  4. This earthquake M 1.8 about 15 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.

Where

Epicentre 39.1252, -76.9636. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Howard County, MD 15 km (9 mi) SSW of here earthquakes near Howard County
Montgomery County, MD 21 km (13 mi) E of here earthquakes near Montgomery County
District of Columbia, DC 25 km (16 mi) N of here earthquakes near District of Columbia
Arlington County, VA 30 km (19 mi) NNE of here earthquakes near Arlington County
Falls Church city, VA 32 km (20 mi) NE of here earthquakes near Falls Church city
Prince George's County, MD 34 km (21 mi) NNW of here earthquakes near Prince George's County

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

Aftershocks so far

1 earthquake has been recorded within 50 km since this one.

  1. 2.5 4 km E of Riverside, Maryland

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.