QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

Earthquake near Baltimore, MD

No earthquake was likely felt in Baltimore in the 24 hours to 4:57 am EST (09:57 UTC). The last one was M 2.5, 23 km (14 mi) WSW, at 5:17 pm EDT on 27 October 2025, estimated intensity II (weak) in town; 1,228 felt reports to USGS. Every earthquake near Baltimore

This page: a magnitude 1.5 earthquake was recorded 38 km (23 mi) west of Baltimore, MD, at 8:34 pm EDT on 29 October 2017 (00:34 UTC), 2.0 km deep.

USGS: 10 km NE of Laytonsville, Maryland

42 km (26 mi) N of Washington, DC · 19 km (12 mi) NE of Gaithersburg, MD

8:34 pm EDT, Oct 29, 2017 · · 2.0 km deep · released about 5.7 lb of TNT

10 km30 km60 km120 km N Howard County 11 kmMontgomery County 21 kmCarroll County 32 kmFrederick County 37 kmBaltimore city 38 kmBaltimore County 42 kmDistrict of Columbia 42 kmArlington County 45 kmFalls Church city 45 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
8:34 pm EDT on 29 October 2017 ()
Where
38 km (23 mi) west of Baltimore, MD · earthquakes near Baltimore
Magnitude
M 1.5 (ml)
Depth
2.0 km below the surface
Felt
no reports yet
Nearest
Howard County, 11 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2008 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Baltimore, 38 km away, the estimate is intensity I (not felt). 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: Sykesville, Damascus, Highland, Mount Airy, Olney, Ashton-Sandy Spring.

How big was it?

This earthquake released about 5.7 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,900,000× the energy of this one
  3. Around the size people start to feel M 3.0 170× the energy of this one
  4. This earthquake M 1.5 about 5.7 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 39.2795, -77.0512. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Howard County, MD 11 km (7 mi) ESE earthquakes near Howard County
Montgomery County, MD 21 km (13 mi) SW earthquakes near Montgomery County
Carroll County, MD 32 km (20 mi) N earthquakes near Carroll County
Frederick County, MD 37 km (23 mi) NW earthquakes near Frederick County
Baltimore city, MD 38 km (24 mi) E earthquakes near Baltimore city
Baltimore County, MD 42 km (26 mi) ENE earthquakes near Baltimore County

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

Aftershocks so far

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

  1. 2.5 4 km E of Riverside, Maryland
  2. 1.8 1 km NE of Spencerville, Maryland
  3. 2.3 0 km WSW of Rockville, Maryland
  4. 2.0 4 km ESE of Sykesville, Maryland
  5. 1.7 0 km S of Woodlawn, Maryland
  6. 2.1 Clarksville, Maryland
  7. 1.6 1 km NNW of Irvington, Maryland
  8. 2.6 2 km SE of Woodlawn, 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.