Magnitude 5.5 Japan Earthquakes Shake Southern Ibaraki Prefecture

A magnitude 5.5 japan earthquakes event struck southern Ibaraki Prefecture at 7:46 p.m. on Tuesday, shaking a broad stretch of eastern Japan. Japan’s seismic intensity scale put the quake at lower 5, and there was no threat of a tsunami.

The quake occurred at a depth of 50 kilometers. Lower 5 shaking was felt in the city of Ota and the town of Chiyoda in Gunma Prefecture, and in the cities of Kazo and Honjo and the town of Misato in Saitama Prefecture.

Gunma And Saitama Shaking

The lower 5 readings placed the strongest shaking beyond southern Ibaraki Prefecture itself, with Ota and Chiyoda in Gunma and Kazo, Honjo and Misato in Saitama among the places that felt it most strongly. That made the quake a wider regional event, not just a local one near the epicenter.

Level 4 shaking and under was recorded across parts of eastern, western, central and north-eastern Japan. The spread reached far beyond the prefectures closest to the epicenter, giving residents in a wide area a clear sense of the quake’s range.

Southern Ibaraki Prefecture

Southern Ibaraki Prefecture was the center of the event, but the reported intensity shows how far the shaking traveled. Japan’s intensity scale separates the magnitude reading from the strength of shaking on the ground, and this quake registered lower 5 even as level 4 and below extended across multiple regions.

For people in the cities and towns named in Gunma and Saitama, the practical takeaway is immediate: the strongest shaking reported so far was lower 5, and the quake did not bring a tsunami threat. The latest fact on the ground is the footprint of the shaking itself, stretching from the epicenter region into a broad swath of Japan.