Quake risks rise in areas along Nankai Trough: report: VIDEO

Quake risks rise in areas along Nankai Trough: report

source www.japantimes.co.jp

The probability of a strong earthquake occurring in areas along the Nankai Trough within 30 years has risen by 1 to 2 percentage points, a new report has found.

A quake measuring lower 6 or stronger on the Japanese seismic intensity scale of 7 — as powerful as the March 2011 temblor that devastated parts of the Tohoku region — is forecast to hit Japan.

According to the 2016 seismic hazard map, issued by the government’s quake research committee Friday, the probability of a quake of this size hitting the Tokai through Shikoku regions increased by between 1 and 2 percentage points since the last report in 2014.

For quakes originating in ocean trenches and active faults, Chiba showed the highest probability among prefectural capital city government offices, at 85 percent. This was followed by 81 percent for Mito, Ibaraki Prefecture, and Yokohama.

The probability stood at 47 percent for Shinjuku, the point where the Tokyo Metropolitan Government offices are located.

In other findings, the probability of an earthquake occurring in prefectural capital cities along the Nankai Trough was 73 percent for Kochi, 71 percent for Tokushima, 68 percent for Shizuoka and 62 percent for Tsu, Mie Prefecture.

The hazard map was produced based on data as of Jan. 1 this year, meaning the powerful quakes that hit Kumamoto Prefecture and other areas of central Kyushu in April were not reflected in the data.

However, the science ministry plans to reinvestigate the Futagawa and Hinagu fault zones that caused the Kumamoto quakes over the next three years, with the findings to be included in the next report.

The probability of a huge Nankai Trough quake with a magnitude of 8 to 9 occurring in the next three decades is 60 to 70 percent, according to government modeling.

The report found there was also a slight increase in the probability of an earthquake occurring in Aomori Prefecture and the Pacific Ocean side of Hokkaido, along the Japan and Chishima ocean trenches.

The hazard map showed that the Kanto, Chubu and Kinki regions that cover the nation’s three major metropolitan areas of Tokyo, Nagoya and Osaka are vulnerable to shaking due to soft ground.

Naoshi Hirata, professor at the University of Tokyo and chief of the quake research committee, said that areas with a lower quake probability could be affected by strong shaking if a powerful quake occurred.

Learning lessons from the Kumamoto quakes, buildings need to be made quake-resistant and furniture firmly fixed, Hirata said.

http://www.japantimes.co.jp/news/2016/06/13/national/quake-risks-rise-in-areas-along-nankai-trough-report/#.V8gUv1uLTtQ

kcontents