Chikyu's journey to the center of the earth

Japan has recently launched the $540 million Chikyu ship to better understand how the underlying crustal plates are interacting with the Japanese archipelago.

Japanese people are living in a very dangerous place, with their archipelago sitting on the top of at least three active tectonic plates. So you can understand why they want to study the earth's mantle to learn more about the interaction between these crustal plates. They recently launched the $540 million Chikyu ship -- Chikyu meaning Earth in Japanese -- just for that purpose. According to Scientific American, this humongous vessel is weighing 57,500 tons for a length of 210 meters. And the top of its derrick, which will be able to dig through 7,000 meters of crust, will rise 112 meters above the waterline. This ship will start its exploration operations in October as part of the Integrated Ocean Drilling Program.

Here are some short excerpts from the Scientific American article.

In July technicians in a Nagasaki port completed the final outfitting of the Chikyu (Japanese for planet "Earth") and handed over the colossal 57,500-ton, 210-meter-long white ship to CDEX. The Chikyu, to start crew training around Hokkaido this fall, is being deployed as part of the Integrated Ocean Drilling Program, a long-term effort begun in 2003 and whose main participants are Japan, the U.S. and the European Union.

Below is a picture of the Chikyu ship (Credit:

The Chikyu ship

Here are more details from Scientific American.

Besides being the most sophisticated laboratory on the seas, the science vessel boasts the tallest drilling derrick at 112 meters above the waterline and a drill pipe that is 9.5 kilometers long -- 22 times the height of the Empire State Building. This borer is expected to cut through some 7,000 meters of crust when the Chikyu, which cost about $540 million, is floating in seas up to 2,500 meters deep.

Below is a diagram showing the top of the Chikyu exploration ship (Credit: Japan Agency for Marine-Earth Science and Technology).

A diagram of the Chikyu ship

And for more information about Chikyu, you should pay a visit to the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) web site. Here are some links to the Chikyu home page, its specifications, the drilling process and a photo gallery.

Finally, you might want to read this presentation about the Chikyu deep-sea drilling vessel (PDF format, 4 pages, 146 KB), from which the diagram above was extracted.

Sources: Tim Hornyak, Scientific American, September 26, 2005; and various web sites

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