October 23, 2006 Earthquake: Izu Islands, Japan
A magnitude 6.4 earthquake struck Izu Islands, Japan on October 23, 2006 at 21:17:19 UTC, 11 km below the surface. It caused a tsunami.
Map
Where it struck, with the other significant earthquakes within 200 km. Circles are sized and colored by magnitude; select one for its page.
The earthquake
- Date
- October 23, 2006
- Time
- 21:17:19 UTC
- Place
- Izu Islands, Japan
- Magnitude
- 6.4 (Mw)
- Focal depth
- 11 km (7 mi)
- Tsunami
- Yes: the tsunami it caused
- Epicenter
- 29.351° N, 140.270° E
- Country
- Japan
- Region
- East Asia
- USGS record
- The USGS’s page for this earthquake
The toll
The record gives no deaths, injuries or damage for this earthquake.
What happened
The USGS’s account of the effects of this earthquake.
Recorded (2 JMA) in Chichijima-retto and (1 JMA) on Aoga-shima. Also recorded (1 JMA) in Chiba and Miyagi Prefectures, Honshu.
From the USGS event page for usp000evvx. U.S. Geological Survey text and figures are in the public domain.
Magnitude estimates
The magnitudes the USGS catalog lists for this earthquake, by scale and by who computed them. NCEI’s own scales are in the table above.
| Mag. | Scale | Computed by | Notes |
|---|---|---|---|
| 6.4 | Mwb, body-wave moment | USGS National Earthquake Information Center | Preferred · Reviewed |
| 6.37 | Mw, moment | ISC-GEM global catalog | Final · ±0.1 |
| 6.4 | Mwc, centroid moment | Global CMT project | Preliminary |
| 6.31 | Me, energy | Choy, USGS energy magnitude | Reviewed |
What the record says
NCEI’s account, from the sources it cites.
Recorded (2 JMA) in Chichijima-retto and (1 JMA) on Aoga-shima. Also recorded (1 JMA) in Chiba and Miyagi Prefectures, Honshu. (reference #13456)
Sources NCEI cites
The publications NCEI lists for this record. The numbers match the “reference #” notes in its account above.
- #13456 U.S. Geological Survey (2017 to present). Earthquake Hazards Program, Advanced National Seismic System (ANSS) Comprehensive Catalog of Earthquake Events and Products.
Other significant earthquakes nearby
Within 200 km, the deadliest first.
More
Significant earthquakes of 2006The 2000sEvery quake the USGS located in 2006Recent earthquakes near hereThis day in weather history
Sources
Significant earthquakes from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-10-01. NCEI earthquake 10734. The written accounts and the magnitude estimates are from the USGS earthquake catalog, event usp000evvx, matched to this record by time, place and magnitude.