is a Japanese

scientific drilling Scientific drilling into the Earth is a way for scientists to probe the Earth's sediments, crust, and upper mantle. In addition to rock samples, drilling technology can unearth samples of connate fluids and of the subsurface biosphere, mostly mi ...

ship built for the

Integrated Ocean Drilling Program The Integrated Ocean Drilling Program (IODP) was an international marine research program. The program used heavy drilling equipment mounted aboard ships to monitor and sample sub-seafloor environments. With this research, the IODP documented e ...

(IODP). The vessel is designed to ultimately

drill A drill is a tool used for making round holes or driving fasteners. It is fitted with a bit, either a drill or driver chuck. Hand-operated types are dramatically decreasing in popularity and cordless battery-powered ones proliferating due to ...

beneath the seabed, where the

Earth's crust Earth's crust is Earth's thin outer shell of rock, referring to less than 1% of Earth's radius and volume. It is the top component of the lithosphere, a division of Earth's layers that includes the crust and the upper part of the mantle. The ...

is much thinner, and into the

Earth's mantle Earth's mantle is a layer of silicate rock between the crust and the outer core. It has a mass of 4.01 × 1024 kg and thus makes up 67% of the mass of Earth. It has a thickness of making up about 84% of Earth's volume. It is predominantly so ...

, deeper than any other hole drilled in the ocean thus far. While the planned depth of the hole is significantly less than the Russian

Kola Superdeep Borehole The Kola Superdeep Borehole (russian: Кольская сверхглубокая скважина, translit=Kol'skaya sverkhglubokaya skvazhina) SG-3 is the result of a scientific drilling project of the Soviet Union in the Pechengsky Distric ...

(which reached depth on land), the scientific results are expected to be much more interesting since the regions targeted by ''Chikyū'' include some of the most seismically-active regions of the world. Other deep holes have been drilled by the drill ship JOIDES Resolution during the Deep Sea Drilling Project and the Ocean Drilling Program.

Operation

The Japanese part of the IODP program is called , Japanese for "Earth Discovery". ''Chikyū'' is operated by the Centre for Deep Earth Research (CDEX), a subdivision of the

Japan Agency for Marine-Earth Science and Technology Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

(JAMSTEC). JAMSTEC also operates the DSV Shinkai,

Earth Simulator The is a series of supercomputers deployed at Japan Agency for Marine-Earth Science and Technology Yokohama Institute of Earth Sciences. Earth Simulator (first generation) The first generation of Earth Simulator, developed by the Japanese g ...

supercomputer and other marine scientific research projects. CDEX is responsible for the services to support activities including on-board staffing, data management for core samples and logging; implements engineering site surveys; and conducts engineering developments. CDEX contracts with the Mantle Quest Japan Company for the navigation of the ship. The ''Chikyū Hakken'' program is part of an international scientific collaborative effort with scientists from the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

, ECORD, a consortium consisting of several European countries and Canada, China,

South Korea South Korea, officially the Republic of Korea (ROK), is a country in East Asia, constituting the southern part of the Korea, Korean Peninsula and sharing a Korean Demilitarized Zone, land border with North Korea. Its western border is formed ...

, Australia and New Zealand (ANZIC), and

India India, officially the Republic of India ( Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the ...

Design

D/V ''Chikyū'' was built by the

Mitsui Engineering & Shipbuilding () is a Japanese company. It is listed on the Nikkei 225. Mitsui E&S is one of the companies of the Mitsui Group. Established in 1917 as the Shipbuilding Division of Mitsui & Co. with the first shipyard at Tamano. In 1937 the shipyards bec ...

and launched on 18 January 2002 in

Nagasaki, Nagasaki is the capital and the largest city of Nagasaki Prefecture on the island of Kyushu in Japan. It became the sole port used for trade with the Portuguese and Dutch during the 16th through 19th centuries. The Hidden Christian Sites in the ...

. The ship was outfitted by the

Mitsubishi Heavy Industries is a Japanese multinational engineering, electrical equipment and electronics corporation headquartered in Tokyo, Japan. MHI is one of the core companies of the Mitsubishi Group and its automobile division is the predecessor of Mitsubishi Moto ...

and delivered to JAMSTEC on 29 July 2005. The hull of the ship is long, in width, high, and has an approximate gross tonnage of about . The ship has a draft of and a maximum cruising speed of . The amidships derrick is above sea level, and the

top drive A top drive is a mechanical device on a drilling rig that provides clockwise torque to the drill string to drill a borehole. It is an alternative to the rotary table and kelly drive. It is located at the swivel's place below the traveling block and ...

has a lifting capacity of . Its complement of 150 crew are divided between 100 operators and 50 science personnel, with at sea crew changes handled by

helicopter A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attribut ...

transfer. Key innovations include a

GPS The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of the global navigation satellite sy ...

system and six adjustable computer controlled

azimuth thruster An azimuth thruster is a configuration of marine propellers placed in pods that can be rotated to any horizontal angle (azimuth), making a rudder unnecessary. These give ships better maneuverability than a fixed propeller and rudder system. Ty ...

s ( in diameter) that enable precise positioning to maintain a stable platform during deep water drilling. The maximum drilling water depth for riser drilling is and can support a drill string up to long. The helipad can serve very large helicopters transporting as many as 30 persons per landing.

History

The D/V ''Chikyū'' was built for deep-sea geological scientific research, which now includes not only research of

earthquake An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, from ...

-generating zones in the

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surf ...

's crust but also hydrothermal ventsThe Deep Hot Biosphere Drilling
, Deep Hot Biosphere hydrothermal vents. and

subsea Subsea technology involves fully submerged ocean equipment, operations, or applications, especially when some distance offshore, in deep ocean waters, or on the seabed. The term ''subsea'' is frequently used in connection with oceanography, mari ...

methane hydrate Methane clathrate (CH4·5.75H2O) or (8CH4·46H2O), also called methane hydrate, hydromethane, methane ice, fire ice, natural gas hydrate, or gas hydrate, is a solid clathrate compound (more specifically, a clathrate hydrate) in which a large amou ...

research. On 16 November 2007 ''Chikyū'' began drilling the transect as planned, reaching at the site of a future deep subsea floor observatory. The first stage of four NanTroSEIZE Stages was completed in February 2008. The whole project was envisioned to be completed by 2012. The ship was damaged by the

2011 Tōhoku earthquake and tsunami The occurred at 14:46 JST (05:46 UTC) on 11 March. The magnitude 9.0–9.1 (M) undersea megathrust earthquake had an epicenter in the Pacific Ocean, east of the Oshika Peninsula of the Tōhoku region, and lasted approximately six m ...

on 11 March 2011. The ship was moored off the coast of

Hachinohe, Aomori is a city located in Aomori Prefecture, Japan. , the city had an estimated population of 221,459, and a population density of 725 persons per km2 in 96,092 households, making it Aomori Prefecture's second largest city by population. The city ...

, but was cut loose by the tsunami and collided with a pier of Hachinohe port. One of the six stabilizers was damaged and a hole was made in the bottom. Local preliminary school children who were visiting the ship at the time of the earthquake spent one night on board and were rescued by

Japan Self-Defense Forces The Japan Self-Defense Forces ( ja, 自衛隊, Jieitai; abbreviated JSDF), also informally known as the Japanese Armed Forces, are the unified ''de facto''Since Article 9 of the Japanese Constitution outlaws the formation of Military, armed f ...

helicopters next day. The ship was repaired at a dock in

Shingū, Wakayama 270px, Shingū city hall 270px, Shingū city aerial photograph 270px, Shingū Castle ruins is a city located in Wakayama Prefecture, Japan. , the city had an estimated population of 27,491 in 14649 households and a population density of 110 ...

and returned to service in June 2011.

World record

According to the IODP, on 27 April 2012, ''Chikyū'' drilled to a depth of below sea level, setting a new world record for deep-sea drilling. This record has since been surpassed by the ill-fated ''

Deepwater Horizon ''Deepwater Horizon'' was an ultra-deepwater, Dynamic positioning, dynamically positioned, Semi-submersible platform, semi-submersible offshore drilling Oil platform, rig owned by Transocean and operated by BP. On 20 April 2010, while drilling ...

'' mobile offshore drilling unit, operating on the Tiber prospect in the Mississippi Canyon Field, United States Gulf of Mexico, when it achieved a world record for total length for a vertical drilling string of . The previous record was held by the U.S. vessel ''

Glomar Challenger ''Glomar Challenger'' was a deep sea research and scientific drilling vessel for oceanography and marine geology studies. The drillship was designed by Global Marine Inc. (now Transocean Inc.) specifically for a long term contract with the Americ ...

'', which in 1978 drilled to below sea level in the

Mariana Trench The Mariana Trench is an oceanic trench located in the western Pacific Ocean, about east of the Mariana Islands; it is the deepest oceanic trench on Earth. It is crescent-shaped and measures about in length and in width. The maximum know ...

. On 6 September 2012 Scientific deep sea drilling vessel ''Chikyū'' set a new world record by drilling down and obtaining rock samples from deeper than 2,111 meters below the seafloor off the Shimokita Peninsula of Japan in the northwest Pacific Ocean. In addition, the 27 April 2012 drilling set a record for the depth of water for drilling of . That record still stands.

In popular culture

The D/V ''Chikyū'' is featured and plays a pivotal role in the 2006 film ''

Sinking of Japan is a 2006 Japanese ''tokusatsu'' disaster film directed by Shinji Higuchi. It is an adaptation of the novel '' Japan Sinks'' and a remake of its earlier film adaptation ''Tidal Wave'', both released in the year 1973. It stars Tsuyoshi Kusanagi, ...

''.

References

External links

The Biggest Dig: Japan builds a ship to drill to the earth's mantle
– Scientific American (September 2005)

Official Page for Integrated Ocean Drilling Program

JAMSTEC.

JAMSTEC.

IODP Riser Vessel homepage

T-Limit Expedition
{{DEFAULTSORT:Chikyu Science and technology in Japan Structure of the Earth 2002 ships Japan Agency for Marine-Earth Science and Technology Drillships