Maps and Diagrams

When the Linear No-Threshold (LNT) model (details of this in the book) is applied to a 20 millisievert radiation dose exposure it shows that young girls are five times more susceptible to radiation, and an infant girl seven times more susceptible than a 30-year-old adult male. Young girls are nearly twice as vulnerable as young boys (the reason for this discrepancy is not currently understood).

Japan has the misfortune to be located in the most seismically active area of the planet. Four crustal plates meet near or under the Japanese Archipelago. The Izu Peninsula sits on top of the Philippine Plate. The area south of Mount Fuji sits on the Eurasian (Amurian) Plate, while the area to the north sits on the North American (Okhotsk) plate. To the east of Japan, the Pacific plate, roughly parallel to Japan’s eastern coast, is sliding under the North American plate. It was tension being released along these two plates that caused the devastating 2011 earthquake.

Though quakes in previous centuries have struck the Kanto every 60 to 70 years, there has been no major Tokyo quake since 1923, a situation that can be considered an anomaly. The numbers of minor earthquakes occurring near Tokyo has increased since 2011. Some Japanese seismologists believe these to be a precursor to the next large Tokyo earthquake.

The south of the Kanto region accounts for approximately one third of the nominal GNP of Japan, the world’s third largest economy. A list of the world’s hundred largest corporations, based on gross revenue, includes the following: Toyota, Japan Post Holding, NTT, Hitachi Ltd, Honda Motor Company, Nissan, Panasonic, Sony, Nippon Life Insurance and Toshiba, each one with headquarters in Tokyo. 



As can be seen in the map above, the National Diet Building where both houses of government meet, all major ministries, as well as the headquarters of many Global 500 companies and the Tokyo Stock Exchange, are located on a dozen square kilometres of land to the east and southeast of the Imperial Palace.