Magnitude 5.7 Earthquake Shakes Central Japan, Injuring at Least 22

Central Japan was shaken awake early on Sunday. A magnitude 5.7 earthquake struck western Shizuoka Prefecture at 1:04 a.m. local time on November 8 (16:04 UTC on November 7), at a depth of about 40 kilometres, the Japan Meteorological Agency (JMA) said. The U.S. Geological Survey measured the same event at magnitude 5.5 and placed it 18 kilometres north of Hamamatsu, Shizuoka, at a depth of 38 kilometres.

The quake shattered store windows, knocked items from shelves and sent people fleeing from buildings across a wide area around Aichi Prefecture, including Hamamatsu, the historic capitals of Kyoto and Nara, and Yamanashi Prefecture, home to Mount Fuji, according to local media reports compiled by the Associated Press. At least 22 people were injured. There was no threat of a tsunami.

It was Japan's second notable earthquake in three days, but a very different one from Friday's magnitude 6.1 offshore quake southeast of Hasaki: that event struck far out in the Pacific and hurt no one, while Sunday's struck on land, under a densely populated region.

Strong enough to set records. The strongest shaking reached upper 5 on Japan's seven-level seismic intensity scale in Chita, in neighbouring Aichi Prefecture, with lower 5 recorded in Seto in Aichi, Urugi Village in Nagano, Ena in Gifu and Hamamatsu in Shizuoka, the JMA reported.

An upper-5 reading had not been observed in Aichi since March 1997 — 29 years ago. In western Shizuoka itself, it was the strongest shaking since record-keeping began in 1919, a span of 107 years, according to the JMA figures reported on Sunday. The USGS classified both the fatality risk and the economic impact of the earthquake as GREEN, its lowest alert category, in its automated PAGER assessment.

At least 22 people were injured, according to Japanese media reports, and officials were still gathering information on the damage through Sunday. Counts moved as the morning went on: an emergency official in Aichi Prefecture reported 16 cases of mostly minor injuries, while authorities in Shizuoka said at least three women sought emergency medical care, including a woman in her nineties who injured her shoulder falling from her bed during the shaking.

Individual cases reported by fire departments included a woman in her fifties in Tokoname who was taken to hospital with a fractured ankle, and a man in his forties and a woman in her eighties in Toyota who fell, struck their heads and reached hospital conscious. In Higashiura, parts of the town lost their water supply and water was seen gushing from manholes. Train services were disrupted as operators checked lines after the shaking.

No deaths were reported. The Japanese government set up an emergency liaison office to assess the situation and coordinate the response.

No. The JMA identified no tsunami threat from this earthquake and issued no tsunami warning. The quake was centred on land in western Shizuoka at roughly 40 kilometres deep, and smaller aftershocks were reported after the main tremor.

At an early-morning news conference held shortly after 3 a.m., the JMA urged residents in the areas that shook strongly to stay alert for further earthquakes of up to upper-5 intensity for about a week, with the likelihood of a large earthquake particularly high over the next two to three days. Agency official Ebita Ayataka also warned that strong shaking combined with rain raises the risk of falling rocks and landslides.

The agency separately assessed the link between Sunday's quake and the long-feared Nankai Trough megaquake as low, saying the pattern of this earthquake differs from that scenario.

WorldEye's earthquake tracker plots the latest USGS-catalogued earthquakes on the same live globe as the site's 74,229 cameras, so a felt event like Sunday's can be checked against the sequence around it — including Friday's offshore magnitude 6.1 and the smaller aftershocks that follow a land event like this one.

For official word in Japan, the JMA's seismic intensity reports remain the reference: its magnitude, intensity readings and aftershock guidance are what the figures in this story are drawn from.