QuakeIndex

Earthquake · reviewed by a seismologist

M 5.1mww

108 km ENE of Miyako, Japan

· 35 km deep · released about 670 tons of TNT

10 km30 km60 km120 km N
Distance rings around the epicentre, with the nearest towns at their true direction. Not a shaking map — see the USGS ShakeMap for that.
When
Magnitude
M 5.1 (mww)
Depth
35 km below the surface
Felt
1 report · strongest reported intensity II
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2 hours ago

This was a moderate earthquake. Shaking at this size can damage poorly built structures close to the epicentre. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 670 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 6.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 250× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11× the energy of this one
  3. Magna, Utah 2020 M 5.7 7.9× the energy of this one
  4. This earthquake M 5.1 about 670 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 1,400× 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 in our catalogue was M 4.4 on 2026-09-22.

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 39.8778, 143.1734. Map © OpenStreetMap contributors.

Aftershocks so far

No further earthquakes have been recorded within 50 km since this one.

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.

Revisions

USGS refines a solution as more stations report. Every change we have seen is listed here.

What changedFromToWhen
reported intensitynot reported2.2
felt reportsnot reported1

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.