Strong M6.3 earthquake hits Izu Islands – third M6+ in 3 days, Japan

A strong and shallow earthquake registered by the JMA as M6.3 hit Izu Islands, Japan at 01:31 UTC on October 6, 2023. The agency is reporting a depth of 10 km (6.2 miles). USGS and EMSC are reporting M6.1 at a depth of 10 km.

The epicenter was located 524.6 km (326 miles) S of Shimoda, Shizuoka, Japan.

According to the JMA, slight sea level changes were expected on nearby islands. No major tsunami warnings or advisories are currently in effect.

The USGS issued a Green alert for shaking-related fatalities and economic losses. There is a low likelihood of casualties and damage.

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.

This is the third M6+ earthquake to hit this region after M6.3 on October 3 and M6.6 on October 5.

Estimated population exposure to earthquake shaking

Regional seismicity

Featured image credit: TW/SAM, Google