Japanese researchers say there is a 70 percent chance of a 7.0 magnitude or higher earthquake to strike the country's capital of Tokyo within the next four years. AFP reported the findings that followed research after the 9.0 magnitude Tohoku Earthquake in March, after which seismic activity in the Tokyo region increased noticeably. The prediction from the Japanese government is less disturbing -- a 70 percent chance of such an earthquake within the next 30 years.
Increased Seismic Activity in Tokyo
Researchers from the University of Tokyo stated that after the March 11 Tohoku Earthquake, Tokyo has seen a marked increase in small earthquakes ranging in magnitude from 3.0 to 6.0. The researchers hold this increase points to a higher probability of a large quake striking the city.
The Great Tokyo Earthquake
While the 9.0 earthquake wreaked havoc on the northern part of the country, Tokyo last saw massive death and destruction from an earthquake in 1923, according to the U.S. Geological Survey. That quake measured at 7.9 in magnitude. It caused massive destruction in Tokyo and Yokohama, and caused the partial or complete destruction of 694,000 homes. Firestorms that resulted from the quake were responsible for about 381,000 of the 694,000 homes destroyed. The Great Tokyo Earthquake of 1923 is among the top 10 most destructive earthquakes in the world.
Larger Population Today Than in 1923
The population of Tokyo in 1920 was about 3.7 million and the death toll from the Great Tokyo Earthquake was 142,800. In comparison, as of 2009, Tokyo had a population of almost 13 million. Tokyo is perhaps the most densely populated area in the country with almost 6,000 people per square kilometer, according to the Tokyo Metropolitan Government website.
Tokyo Sits on Three Tectonic Plates
According to Oregon State University's Volcano World website, Tokyo is on the convergence of three tectonic plates -- the Eurasian, the Pacific and the Philippine plates. Japan sees numerous earthquakes of all magnitudes as well as volcanic activity due to subduction of the Pacific and Philippine plates under the Eurasian plate.
Building Codes and Preparation Decreases Risk
A large earthquake would cause extensive damage to a city the size of Tokyo, but buildings in modern-day Japan are built to fare better. It was thanks to emphasis placed on emergency preparation and strict building codes that more lives were not lost after the Tohoku Earthquake.
The New York Times reported in March that emergency drills and building practices reduced the amount of destruction and the death toll from that earthquake and tsunami.
Tammy Lee Morris is certified as a Community Emergency Response Team (CERT) member and is a trained Skywarn Stormspotter through the National Weather Service. She has received interpretive training regarding the New Madrid Seismic Zone through EarthScope -- a program of the National Science Foundation. She researches and writes about earthquakes, volcanoes, tornadoes, weather and other natural phenomena.
- Nature & Environment
- Nature & Environment/Natural Phenomena
- Great Tokyo Earthquake