Riser ships encase the drill bit in a pipe, allowing the driller to protect against accidental oil spills, to flush out debris, and to keep the hole from collapsing. The new ship's primary mission is to investigate earthquake zones off the coast of Japan. But in the back of everyone's mind lies that holy grail, the mantle, which a vessel of this magnitude could conceivably reach. The world's ocean drilling community has once again made going to the mantle an explicit goal, and the operating costs of the vessel will likely come from the United States and other interested countries. Within 15 years, scientists hope to drill through a complete slice of oceanic crust.
Geologists have mantle rocks sitting in their labs.
Last year, for example, Australian geochemists announced that they'd stumbled on rocks that originated 435 miles beneath the Earth's surface. An undisturbed sample taken from within the Earth would reveal more about the real composition of the mantle. Naysayers argue that the Japanese ship will never reach the mantle with riser technology, which has never taken the oil industry so far down. While the ship will be complete in 2004 and will immediately start drilling shallow holes, Japanese researchers estimate they won't finish the equipment for going to the mantle until 2012. The drilling itself would then take a solid two years.