Tuesday, April 3, 2012

Tokyo - Subduction

I'd heard a lot about the vast and grand city of Tokyo so I decided that that would be the first destination of my worldwide adventure.  Tokyo is in Japan which is located in the very eastern part of Asia, or more exactly, at 35.6833° N, 139.7667° E.  I left my hometown city of Seattle and caught a flight to Tokyo in the Sea-Tac international airport.  After roughly 14 hours I finally arrived in Tokyo at dusk.  As my plane started descending I watched the bright city's skyline and thought how it made Seattle look puny. I landed in the Narita International Airport and caught a taxi to my hotel.

Narita International Airport - http://tinyurl.com/7hs987e

Hotel Metropolitan - http://tinyurl.com/6tb95r3

I arrived at the elegant Hotel Metropolitan and I was eager to get straight to bed after a very long 14 hours in a plane.  In the morning I had a monstrous breakfast which consisted of fried eggs, pancakes, sausage and orange juice.  Next I wandered the busy and bustling streets of downtown Tokyo, as tourists do, feeling small and not exactly sure what to do and where to go.  I walked by the National Science Museum and decided to take a peek inside.  

National Science Museum, Tokyo - http://tinyurl.com/83zhmbb
There was so interesting stuff in that building. I could have spent the entire day there!  I learned many things but the most interesting thing that I learned was about Tokyo itself.  I learned that Tokyo's geographical location is right next to a subduction boundary.  I had always wondered how geographic features such as volcanoes and trenches were made and now I know.  In this case the oceanic Pacific Plate is subducting under the Okhotsk Plate (Tokyo is on the Okhotsk Plate).   


As depicted in the picture above, when two tectonic plates (one continental and one oceanic) move towards each other multiple things happen.  The denser, oceanic plate (the oceanic Pacific Plate in Tokyo's case) goes under the less dense, continental plate.  As the oceanic Pacific Plate sinks further and further into the earth it heats up more and more until much of it melts and turns into magma. 

Mount Meakan - http://tinyurl.com/745mgdn

This magma is very hot and less dense than its surroundings so it travels back to the surface of the earth.  This creates enough pressure to let the magma force itself through the other plate (the Okhotsk Plate in Tokyo's case).  This process is what creates volcanoes.

I decided to visit one of Japan's fabulous volcanoes, Mount Meakan (photo above). It's an active volcano an it's last eruption was on the 31st of March in 2006.  Am i ever glad that it didn't erupt when i was there!

Mount Meakan is one of the 108 active volcanoes in Japan.  47 volcanoes are remarkably active and on average there are about 15 volcanic events every year.  The most recent volcanic eruption in Japan was when Sakurajima erupted on the 26th of February in 2012.  Here's a video that depicts the eruption: http://www.youtube.com/watch?v=qMTQCUw8qCA

The dark blue in the photo above depicts the under-water trenches that are being created by the oceanic Pacific Plate subducting under the Okhotsk Plate - http://tinyurl.com/76c9ou2

Subduction zones also create impressive trenches.  The picture above shows a vast underwater trench created by the oceanic Pacific Plate subducting under the Okhotsk Plate.  Trenches are formed right where the continental plate starts to "overlap" the oceanic plate by subduction as I told you about before.  

Damage caused by earthquakes in Japan - http://tinyurl.com/7qbejyc

Unfortunately, where there are subduction zones, there are earthquakes.  These earthquakes are caused by the incredible amount of friction that is created by the two plates moving towards each other.  Earthquakes happen quite frequently, in fact a 4.4 Magnitude earthquake hit Hidaka-chiho Seibu, Japan just yesterday (April 21st, 2012).

Well enough of Tokyo and lovely Japan.  I decided that I love visiting these tectonic boundaries so off to my second destination, Los Angeles! 

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