Marine Ecosystems Research Department - jamstec japan agency ...

Japan Marine Science and Technology Center
Research Activities
OD21 Program Department
Outline of the Ocean Drilling in the 21st Century (OD21)
The Ocean Drilling in the st Century (OD) is the ultimate project seeking to comprehensively understand the
whole global system, and establishes a new era in earth and life science by verifying the mechanisms of crustal
movement, elucidating the dynamic evolution of the global environment, and exploring the unknown deep biosphere.
This analysis is accomplished by studying core samples, monitoring the boreholes, and drilling into seismogenic
zones, which are thought to cause major impacts such as earthquakes and tsunamis. With existing platforms, it
is almost impossible, or quite difficult, to drill directly into the zones. The OD intends to build and operate the
unique deep sea drilling vessel "CHIKYU", which is the first scientific drillship to be equipped with a riser system,
and has the most advanced scientific drilling capability in the world.
Meanwhile the Ocean Drilling Program (ODP) led by U.S. achieved outstanding results in the late th century,
such as the substantiation of plate tectonics, elucidation of the dynamic evolution of the global environment and discovery
of the new deep biosphere. From October onwards, the ODP will be integrated with the OD into the
Integrated Ocean Drilling Program (IODP) under the co-leadership of Japan and U.S. The IODP is an international
project which mainly utilizes two drilling vessels: one is the riser drilling vessel "CHIKYU" to be provided by
Japan, and the other is a non-riser drilling vessel to be provided by the U.S.
The IODP, operating unprecedented large-scale and powerful facilities including "CHIKYU", aims to achieve significant
advances in the geoscience and life science field for the st century, which will create a new wisdom for
all human beings. The IODP will also address themes that help to find solutions for world issues, such as reduction
of natural disasters, and through this, contribute to the further improvement of living standards for humankind.
Japan Marine Science and Technology Center (JAMSTEC) is the overall coordinating and promoting organization
for the IODP in Japan. The OD Program Office in JAMSTEC is responsible for the construction of
"CHIKYU" and development of associated technologies, setup of the "CHIKYU" operational structure, and arrangement
of the domestic/international supporting structures.
1. Development of Technologies for Exploration
of the Earth's Deep Interior
(1) Construction of Ultra Deep Water Drilling Vessel
The ultra deep water drilling vessel CHIKYU
(Figure , ), to be operated in OD, is a riser
drilling vessel, and is the first scientific drilling vessel
to apply mud circulation, a technology commonly
used for petroleum exploration. CHIKYU aims to penetrate
to a depth of , meters in the ocean floor up
to a water depth of , meters (, meters in the
future) all over the world, except icebound seas.
CHIKYU is equipped with facilities to collect continuous
cylindrical core samples of sedimentary rocks or
igneous rocks by drilling, to conduct various physical
and chemical measurements in boreholes, to analyze
obtained core samples and to interpret data on geological
formations. Standard outer diameter of core
samples obtained in the drilling is approximately
mm and it is comparable to that of the Ocean
Drilling Program (ODP). Table shows the major
specifications of CHIKYU.
As the objective of CHIKYU is scientific drilling, it
must be able to drill the seafloor of all sea areas in the
world. In order to achieve this, severe conditions are
set for the structural design of the vessel. Design condition
on the wind velocity is .m/s, and on the significant
wave height is equivalent to that expected
once in years, in the long-range wave data of the
Global Wave Statistics (published by the British
Maritime Technology). CHIKYU is also designed to
be able to carry out drilling operation safely and effectively
under harsh meteorological and oceanographic
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