Shaking intensity
- III
- IV
Strongest contour: Light (IV). Modelled by USGS ShakeMap; contours show where shaking was expected to reach each level, not damage.
Who felt it
People in the shaking
- IVLight1.7 million
- IIIWeak413,000
| Place | Population | Shaking |
|---|---|---|
| Tonosho | 13,000 | IV |
| Oarai | 16,000 | IV |
| Kamisu | 95,000 | IV |
| Itako | 27,000 | IV |
| Kashima | 67,000 | IV |
| Choshi | 58,000 | IV |
| Ibaraki | 31,000 | IV |
| Namegata | 32,000 | IV |
Past earthquakes here. A magnitude 6.6 earthquake 265 km s of this event struck Niigata, Japan on October 23, 2004 (UTC), with estimated population exposures of 347,000 at intensity VIII and 76,000 at intensity IX or greater, resulting in a reported 48 fatalities.
Local buildings. Overall, the population in this region resides in structures that are resistant to earthquake shaking, though vulnerable structures exist. The predominant vulnerable building types are heavy wood frame and reinforced/confined masonry construction.
Population and intensity modelled by USGS PAGER. Estimates, not a count of people affected.
Official source
View the USGS record ↗U.S. Geological Survey
Terremoto preserves this event snapshot for a stable public link. USGS remains the authoritative source for revisions and scientific details. Shaking contours and population estimates come from USGS ShakeMap and PAGER, which revise them as more data arrives.