JAMSTEC developed the deep sea scientific drilling vessel CHIKYU to drill the sea floor, recover core samples, and analyze these on board to obtain important scientific information. The most important of these information, previously targeted by Integrated Ocean Drilling Program (IODP), includes the studies of deep biosphere, environmental change, and solid earth cycle. CHIKYU was delivered to JAMSTEC in July 2005 and the shakedown, training, System Integration Tests (SITs) were initiated shortly thereafter. JAMSTEC will start the scientific drilling operation for IODP beginning in September 2007. The first site for drilling is planned at the Nankai Trough where the subduction plate boundary was the source of many great earthquakes repeatedly. This paper describes basic characteristics of CHIKYU and the planned functions, summarizes soon to be completed SIT results and lists the planned technological enhancements for CHIKYU.
The original concept for scientific ocean drilling was born at one academic association breakfast from a casual remark made by Prof. Walter Munk of Scripps Institution of Oceanography. Professor Munk's remark was taken a step further at the first International Oceanographic Congress in 1959. During the conference Roger Revelle announced the Mohole Project, a plan for the world's first deep sea drilling operation to penetrate through the Moholovicic Discontinuity in the Eastern Pacific Ocean. They prepared a 3,000 tons class vessel, CUSSI, modified the vessel and equipped it with the drilling equipments, and drilled to a penetration of 171 m sediments and 6 m basalt at the 3,560 m water depth. However, the full Mohole project objectives were not achieved until another research idea of the paleo-environment utilizing ocean drilling operation and the implementation of the next Deep Sea Drilling Project (DSDP) with a 10,000 tons class vessel, Glomar Challenger in 1968.