1923 Great Kanto Earthquake
The 1923 Great Kanto Earthquake is the last major earthquake to hit the Tokyo area. At a magnitude of 7.9 - some reports say as much as 8.3 - it flattened the majority of Tokyo as well as surrounding areas.
However, not all the damage came directly from the earthquake itself. It was coming up to lunchtime on that fateful 1st of September and many people were preparing their food over open fires. At that time, the majority of buildings were made from wood and, as a result, fire spread quickly from house to house, ensuring the destruction of the city.
The Imperial Hotel Remains Standing
One of the few buildings to remain standing, after the dust had settled, was the Imperial Hotel Tokyo designed by Frank Lloyd Wright. This was one of the first buildings to be constructed to allow different sections of the walls to move independently from each other - and it worked. The Imperial Hotel was lucky enough to also have enough space around it so that it remained unaffected by the spreading fires. This is a section from a diary of a guest staying at the hotel at that time - it's an interesting read with some insights into the tragedies that people suffered that day.
What Causes Earthquakes in Tokyo?
The whole of Japan sits on an extremely active part of the earth's crust and the Tokyo area is no exception. The 1923 Great Kanto earthquake, along with the multitude of more minor earthquakes that occur daily, are caused by Tokyo's location on top of 3 tectonic plates - the Eurasion Plate, the Phillipine Plate and the Pacific Plate. The nature of these plates is that they dip underneath each other, so when one plate moves it pushes the others down or up.
For those of you who are interested, in contrast to the above, the San Andreas fault in California consists of 2 plates that rub sideways against each other creating a different kind of movement.
Types of Earthquake
Forgive me here, there is a technical name for what I am about to describe, but I can't for the life in me remember what it is, and the searches I've done are bringing back everything but the information I want!
Anyway - the shaking of the earth caused by an earthquake produces 2 kinds of movement. The most common type is a side-to-side movement which allows buildings and man made structures to sway. Of course, if the quake is strong enough, then the degree of sway may become too much, causing structural damage. The second, and most deadly kind of earthquake, is an up-and-down movement. This sudden jolting causes buildings to effectively jump in the air - how high depends again on the magnitude of the quake. Just as with gymnastics, you hope your building scores a perfect 10 and lands squarely back on it's foundations.
If anyone knows the names for these 2 types of movement, please let me know using the Contact Us form as it's really bugging me!
