The fierce earthquake that struck Niigata and Nagano prefectures Monday reminded both the government and the public of the need to make Japan more resilient toward earthquakes. The magnitude-6.8 quake was focused about 60 km southwest of the city of Niigata and some 17 km below the bottom of the Sea of Japan. Its maximum intensity registered an upper 6 on the Japanese scale of 7. It did not occur in a submarine trench where the Pacific tectonic plate slips under the continental tectonic plate; instead, a strain in the continental plate caused a fault to slip.
In March, a similar, magnitude-6.9 quake also occurred in the Sea of Japan, seriously impacting the Noto Peninsula in Ishikawa Prefecture. In October 2004, the inland area of Niigata Prefecture had been hit by a magnitude-6.8 quake of the same type. It must be remembered that strains in the continental plate are said to exist in many parts of Japan.
Most of the nine deaths in the latest quake occurred when people were pinned down by structures or furniture. More than 800 houses were flattened or damaged and about 980 people injured. Although 1981 regulations stipulate that buildings must withstand a quake of upper-6 intensity, a quarter of Japan's houses are estimated to lack such resistance. The central and local governments should provide necessary subsidies to make houses quake-proof. Fastening furniture in place is also important.