Saturday, March 31, 2012

Projected Tokyo quake to hit top intensity over wider area; science ministry

A powerful inland earthquake expected to occur in the Tokyo metropolitan area is likely to register 7 on the 7-point Japanese intensity scale over the largest area if it hits near the Tokyo-Chiba border, according to a science ministry research team estimate.

The team of experts set up by the Education, Culture, Sports, Science and Technology Ministry announced the estimate on March 30.

The estimate has prompted the national government to review its damage projections for such a massive disaster, as well as its disaster-prevention measures, and will pressure local bodies in the region to reconsider their quake preparedness.

Team member and University of Tokyo professor Kazuki Koketsu urges all areas in the region to be prepared for a powerful quake, regardless of the estimate.

"The estimate was made based on various assumed conditions, so the distribution of the intensity scales will shift a great deal if those conditions are changed," he says. "Not only areas where strong vibrations are expected but also all areas in southern Kanto should be prepared for a powerful quake."

The team, comprised mainly of University of Tokyo's Earthquake Research Institute researchers, surveyed the subsurface structure of the metropolitan area using seismometers at 296 locations in Tokyo and its vicinity. Read More