Earthquake · reviewed by a seismologist
M 4.9mww
2 km SW of Sakai, Japan
- When
- Magnitude
- M 4.9 (mww)
- Depth
- 71 km below the surface
- Felt
- 27 reports · strongest reported intensity IV
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 42 minutes ago
This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 27 people have reported feeling it to USGS.
How big was it?
This earthquake released about 340 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.9 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 500× the energy of this one
- Mineral, Virginia 2011 M 5.8 22× the energy of this one
- Magna, Utah 2020 M 5.7 16× the energy of this one
- This earthquake M 4.9 about 340 tons of TNT
- Around the size people start to feel M 3.0 this one released 710× 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.
Revisions
USGS refines a solution as more stations report. Every change we have seen is listed here.
| What changed | From | To | When |
|---|---|---|---|
| felt reports | 24 | 27 | |
| felt reports | 23 | 24 | |
| felt reports | 22 | 23 | |
| felt reports | 16 | 22 | |
| felt reports | 11 | 16 | |
| felt reports | 9 | 11 | |
| reported intensity | not reported | 4.3 | |
| felt reports | not reported | 9 |
Where
Epicentre 36.0809, 139.7782. 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.
On USGS
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.