ABISMO
Encyclopedia

ABISMO (Automatic Bottom Inspection and Sampling Mobile) is a remotely operated underwater vehicle (ROV) built by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) for exploration of the deep sea
Deep sea
The deep sea, or deep layer, is the lowest layer in the ocean, existing below the thermocline and above the seabed, at a depth of 1000 fathoms or more. Little or no light penetrates this part of the ocean and most of the organisms that live there rely for subsistence on falling organic matter...

. One of only two ROVs rated to 11,000-meters (the other one being Nereus
Nereus (underwater vehicle)
Nereus is a hybrid autonomous underwater vehicle built by the Woods Hole Oceanographic Institution . Constructed as a research vehicle to operate at depths of up to , it was designed to explore Challenger Deep, the deepest surveyed point in the global ocean...

, built and operated by the Woods Hole Oceanographic Institution
Woods Hole Oceanographic Institution
The Woods Hole Oceanographic Institution is a private, nonprofit research and higher education facility dedicated to the study of all aspects of marine science and engineering and to the education of marine researchers. Established in 1930, it is the largest independent oceanographic research...

), ABISMO is intended to be the permanent replacement for Kaikō
Kaiko
was a remotely operated underwater vehicle built by the Japan Agency for Marine-Earth Science and Technology for exploration of the deep sea. Kaikō was the second of only three vessels ever to reach the bottom of the Challenger Deep, as of 2010...

, a ROV that was lost at sea in 2003.

Challenger Deep

Bathymetric
Bathymetry
Bathymetry is the study of underwater depth of lake or ocean floors. In other words, bathymetry is the underwater equivalent to hypsometry. The name comes from Greek βαθύς , "deep", and μέτρον , "measure"...

 data obtained during the course of the expedition
Challenger expedition
The Challenger expedition of 1872–76 was a scientific exercise that made many discoveries to lay the foundation of oceanography. The expedition was named after the mother vessel, HMS Challenger....

 (December 1872 – May 1876) of the British Royal Navy
Royal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

 survey ship HMS Challenger
HMS Challenger (1858)
HMS Challenger was a steam-assisted Royal Navy Pearl-class corvette launched on 13 February 1858 at the Woolwich Dockyard. She was the flagship of the Australia Station between 1866 and 1870....

 enabled scientists to draw maps, which provided a rough outline of certain major submarine terrain features, such as the edge of the continental shelves
Continental shelf
The continental shelf is the extended perimeter of each continent and associated coastal plain. Much of the shelf was exposed during glacial periods, but is now submerged under relatively shallow seas and gulfs, and was similarly submerged during other interglacial periods. The continental margin,...

 and the Mid-Atlantic Ridge
Mid-Atlantic Ridge
The Mid-Atlantic Ridge is a mid-ocean ridge, a divergent tectonic plate boundary located along the floor of the Atlantic Ocean, and part of the longest mountain range in the world. It separates the Eurasian Plate and North American Plate in the North Atlantic, and the African Plate from the South...

. This discontinuous set of data points was obtained by the simple technique of taking soundings
Sounding line
A sounding line or lead line is a length of thin rope with a plummet, generally of lead, at its end. Regardless of the actual composition of the plummet, it is still called a "lead."...

 by lowering long lines from the ship to the seabed
Seabed
The seabed is the bottom of the ocean.- Ocean structure :Most of the oceans have a common structure, created by common physical phenomena, mainly from tectonic movement, and sediment from various sources...

. Among the many discoveries of the Challenger expedition was the identification of the Challenger Deep. This depression, located at the southern end of the Mariana Trench
Mariana Trench
The Mariana Trench or Marianas Trench is the deepest part of the world's oceans. It is located in the western Pacific Ocean, to the east of the Mariana Islands. The trench is about long but has a mean width of only...

 near the Mariana Islands
Mariana Islands
The Mariana Islands are an arc-shaped archipelago made up by the summits of 15 volcanic mountains in the north-western Pacific Ocean between the 12th and 21st parallels north and along the 145th meridian east...

 group, is the deepest surveyed
Surveying
See Also: Public Land Survey SystemSurveying or land surveying is the technique, profession, and science of accurately determining the terrestrial or three-dimensional position of points and the distances and angles between them...

 point of the World Ocean
World Ocean
The World Ocean, world ocean, or global ocean, is the interconnected system of the Earth's oceanic waters, and comprises the bulk of the hydrosphere, covering almost 71% of the Earth's surface, with a total volume of 1.332 billion cubic kilometres.The unity and continuity of the World Ocean, with...

. The Challenger scientists made the first recordings of its depth on 23 March 1875 at station 225. The reported depth was 4,475 fathom
Fathom
A fathom is a unit of length in the imperial and the U.S. customary systems, used especially for measuring the depth of water.There are 2 yards in an imperial or U.S. fathom...

s (8184 m) based on two separate soundings.

On 23 January 1960, Don Walsh
Don Walsh
Don Walsh is an American oceanographer, explorer and marine policy specialist. He and Jacques Piccard were aboard the bathyscaphe Trieste when it made a record maximum descent into the Mariana Trench on 23 January 1960, the deepest point of the world's ocean...

 and Jacques Piccard
Jacques Piccard
Jacques Piccard was a Swiss oceanographer and engineer, known for having developed underwater vehicles for studying ocean currents. He was one of only two people, along with Lt...

 were the first men to descend to the bottom of the Challenger Deep in the Trieste bathyscaphe
Bathyscaphe
A bathyscaphe is a free-diving self-propelled deep-sea submersible, consisting of a crew cabin similar to a bathysphere, but suspended below a float rather than from a surface cable, as in the classic bathysphere design....

. Though the initial report claimed the bathyscaphe had attained a depth of 37,800 feet, the maximum recorded depth was later calculated to be 10,911 meters. At this depth, the water column above exerts a barometric pressure of 108.6 megapascals (15,751.1 psi), over one thousand times the standard atmospheric pressure at sea level. However, even at this great depth and pressure, a small flounder
Flounder
The flounder is an ocean-dwelling flatfish species that is found in coastal lagoons and estuaries of the Northern Atlantic and Pacific Oceans.-Taxonomy:There are a number of geographical and taxonomical species to which flounder belong.*Western Atlantic...

-like fish was seen moving away from the spotlight of the bathyscaphe. Since then, no manned vessel has ever returned to the Challenger Deep.

In March 1995, Kaikō
Kaiko
was a remotely operated underwater vehicle built by the Japan Agency for Marine-Earth Science and Technology for exploration of the deep sea. Kaikō was the second of only three vessels ever to reach the bottom of the Challenger Deep, as of 2010...

became the second vessel ever to reach the bottom of the Challenger Deep
Challenger Deep
The Challenger Deep is the deepest known point in the oceans, with a depth of to by direct measurement from submersibles, and slightly more by sonar bathymetry . It is located at the southern end of the Mariana Trench near the Mariana Islands group...

, and the first craft to visit this location since the Trieste mission. The maximum depth measured on that dive was 10,911.4 meters, marking the deepest dive for an unmanned submersible to date. On 31 May 2009, Nereus became the third vessel to visit the bottom of the Challenger Deep
Challenger Deep
The Challenger Deep is the deepest known point in the oceans, with a depth of to by direct measurement from submersibles, and slightly more by sonar bathymetry . It is located at the southern end of the Mariana Trench near the Mariana Islands group...

, reaching a maximum recorded depth of 10,902 meters.

Kaikō

Between 1995 and 2003, Kaikō conducted more than 250 dives, collecting 350 biological species (including 180 different bacteria), some of which could prove to be useful in medical and industrial applications. Kaikō reached a maximum depth of 10,911.4 meters at the Challenger Deep on 24 March 1995, during its initial sea trials. Kaikō returned to Challenger Deep in February 1996, this time reaching a maximum depth of 10,898 meters. Kaikō made its last visit to Challenger Deep in May 1998. On 29 May 2003, Kaikō was lost at sea off the coast of Shikoku Island
Shikoku
is the smallest and least populous of the four main islands of Japan, located south of Honshū and east of the island of Kyūshū. Its ancient names include Iyo-no-futana-shima , Iyo-shima , and Futana-shima...

 during Typhoon Chan-Hom, when a steel secondary cable connecting it to its launcher at the ocean surface broke. In May 2004, JAMSTEC resumed its research operations, using a converted ROV as its vehicle. This ROV, formerly known as UROV 7K, was rechristened Kaikō7000II. The 7000 designation indicates that this vessel is rated for diving to a maximum depth of 7,000 meters.

RV Kairei

RV Kairei is a deep sea research vessel that served as the support ship for Kaikō, and for its replacement ROV, Kaikō7000II. It now serves as the support ship for ABISMO. Kairei uses ABISMO to conduct surveys and observations of oceanic plateau
Oceanic plateau
An oceanic plateau is a large, relatively flat submarine region that rises well above the level of the ambient seabed. While many oceanic plateaus are composed of continental crust, and often form a step interrupting the continental slope, some plateaus are undersea remnants of large igneous...

s, abyssal plain
Abyssal plain
An abyssal plain is an underwater plain on the deep ocean floor, usually found at depths between 3000 and 6000 metres. Lying generally between the foot of a continental rise and a mid-ocean ridge, abyssal plains cover more than 50% of the Earth’s surface. They are among the flattest, smoothest...

s, oceanic basin
Oceanic basin
Hydrologically, an oceanic basin may be anywhere on Earth that is covered by seawater, but geologically ocean basins are large geologic basins that are below sea level...

s, submarine volcano
Submarine volcano
Submarine volcanoes are underwater fissures in the Earth's surface from which magma can erupt. They are estimated to account for 75% of annual magma output. The vast majority are located near areas of tectonic plate movement, known as ocean ridges...

es, hydrothermal vent
Hydrothermal vent
A hydrothermal vent is a fissure in a planet's surface from which geothermally heated water issues. Hydrothermal vents are commonly found near volcanically active places, areas where tectonic plates are moving apart, ocean basins, and hotspots. Hydrothermal vents exist because the earth is both...

s, oceanic trench
Oceanic trench
The oceanic trenches are hemispheric-scale long but narrow topographic depressions of the sea floor. They are also the deepest parts of the ocean floor....

es and other underwater terrain features to a maximum depth of 11,000 meters. Kairei also conducts surveys of the structure of deep sub-bottoms with complicated geographical shapes in subduction zones using its on-board multi-channel reflection survey system.

Development of ABISMO

While the temporary replacement ROV (Kaikō7000II) has a remarkable performance record, it is only rated to 7,000 meters and cannot reach the deepest oceanic trenches. For this reason, JAMSTEC engineers began work on a new 11,000-meter class of ROV in April 2005. The project is called ABISMO (Automatic Bottom Inspection and Sampling Mobile), which translates to abyss in Spanish.

Like Kaikō, ABISMO consists of 4 major parts:
  1. electronic instruments aboard RV Kairei, the support ship
  2. Launcher (a sampling station)
  3. Vehicle (a sediment probe)
  4. Samplers (a gravity corer or Smith Macintyre type sampler)

Except for the sampler and the smaller size of the ROV itself, the system configuration is the same as for Kaikō. The launcher launches and recovers the ROV along with its sampler. Click here to see a photograph of ABISMO and its launcher, as well as RV Kairei, the support ship.

The lower part of the launcher is constructed of a stainless steel
Stainless steel
In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5 or 11% chromium content by mass....

 framework, within which the vehicle is stored. Pressure hulls
Submarine hull
The term light hull is used to describe the outer hull of a submarine, which houses the pressure hull, providing hydrodynamically efficient shape, but not holding pressure difference...

 for electronic devices, a winch
Winch
A winch is a mechanical device that is used to pull in or let out or otherwise adjust the "tension" of a rope or wire rope . In its simplest form it consists of a spool and attached hand crank. In larger forms, winches stand at the heart of machines as diverse as tow trucks, steam shovels and...

, a secondary cable drum
Cable reel
A cable reel is a round, drum-shaped object such as a spool used to carry various types of electrical wires. Cable reel which can also be termed as drums have been used for many years to transport electric cables, fiber optic cables and wire products...

 and two electric transformer
Transformer
A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer's coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic field...

s are located in the upper part of the launcher. The samplers include a gravity core sampler and a bottom grab sampler. There is also a docking system and an acoustic positioning system in the lower part of the launcher. The vehicle is hung in the launcher by the docking system. When the system detaches it and the cable drum feeds the secondary cable, the vehicle can dive down, and its position is measured by the acoustic positioning system. The position of the launcher is measured by RV Kairei, the support ship. The launcher also has a high-definition television
High-definition television
High-definition television is video that has resolution substantially higher than that of traditional television systems . HDTV has one or two million pixels per frame, roughly five times that of SD...

 (HDTV) camera with pan and tilt functions.

Initial sea trials of ABISMO were conducted in 2007. The craft successfully reached a planned depth of 9,760-meters, the deepest part of Izu-Ogasawara Trench
Izu-Ogasawara Trench
The , also known as Izu-Bonin Trench is an oceanic trench in the western Pacific Ocean. It stretches from Japan to the northernmost section of Mariana Trench. The Izu-Ogasawara Trench is an extension of the Japan Trench...

, where it collected core samples of sediment from the seabed. Plans are underway for a mission to the Challenger Deep.

See also

  • 1948: FNRS-2
    FNRS-2
    The FNRS-2 was the first bathyscaphe. It was created by Auguste Piccard. Work started in 1937 but was interrupted by World War II. The deep-diving submarine was finished in 1948. The bathyscaphe was named after the Belgian Fonds National de la Recherche Scientifique , the funding organization for...

  • 1953: Trieste (DSV-0)
    Bathyscaphe Trieste
    The Trieste is a Swiss-designed, Italian-built deep-diving research bathyscaphe with a crew of two, which reached a record maximum depth of about , in the deepest known part of the Earth's oceans, the Challenger Deep, in the Mariana Trench near Guam, on January 23, 1960, crewed by Jacques Piccard ...

  • 1964: Trieste II (DSV-1)
    Bathyscaphe Trieste II
    Trieste II ' was the successor to Trieste — the United States Navy's first bathyscaphe purchased from its Swiss designers. The original Trieste design was heavily modified by the Naval Electronics Laboratory in San Diego, California and built at the Mare Island Naval Shipyard...

  • 1964: Aluminaut
    Aluminaut
    Aluminaut was built in 1964 and was the world's first aluminum submarine. The 80-ton, 51 foot manned deep-ocean research submersible was built by Reynolds Metals Company, which was seeking to advertise the utility of aluminum...

  • 1964: Alvin (DSV-2)
    DSV Alvin
    Alvin is a manned deep-ocean research submersible owned by the United States Navy and operated by the Woods Hole Oceanographic Institution in Woods Hole, Massachusetts. The vehicle was built by General Mills' Electronics Group in the same factory used to manufacture breakfast cereal-producing...

  • 1984: Nautile
    Nautile
    The Nautile is a manned submersible owned by Ifremer, the French Research Institute for Exploitation of the Sea. Commissioned in 1984, the submersible can be operated at depths of up to ....

  • 1987: MIR
    MIR (submersible)
    Mir is a self-propelled Deep Submergence Vehicle. The project was initially developed by the USSR Academy of Sciences along with Design Bureau Lazurith. Later two vehicles were ordered from Finland...

  • 1990: Shinkai
    DSV Shinkai
    The Shinkai 6500 is a manned research submersible that can dive up to a depth of 6,500 m. It was completed in 1990 and has the greatest depth range of any manned research vehicle in the world. The only manned expedition to have gone deeper was the dive of the Trieste bathyscaphe in 1960. However,...

  • 1993: Kaikō
    Kaiko
    was a remotely operated underwater vehicle built by the Japan Agency for Marine-Earth Science and Technology for exploration of the deep sea. Kaikō was the second of only three vessels ever to reach the bottom of the Challenger Deep, as of 2010...

  • 1994: Explorer
    Explorer AUV
    Explorer Autonomous underwater vehicle is a Chinese AUV developed in the People's Republic of China , first entering service in November 1994, and it should not be confused with another two Anglo-American AUVs that share the same name: the American built by Woods Hole Oceanographic Institution,...

  • 2007: Nereus
    Nereus (underwater vehicle)
    Nereus is a hybrid autonomous underwater vehicle built by the Woods Hole Oceanographic Institution . Constructed as a research vehicle to operate at depths of up to , it was designed to explore Challenger Deep, the deepest surveyed point in the global ocean...

  • 2008: Sea Pole
    Sea Pole class bathyscaphe
    The Sea Pole class bathyscaphe is a class of little known bathyscaphe of the People's Republic of China , capable of diving up to 7,000 metres, covering 99.8% of the oceanic floor of the world...

  • Autonomous underwater vehicle
    Autonomous Underwater Vehicle
    An autonomous underwater vehicle is a robot which travels underwater without requiring input from an operator. AUVs constitute part of a larger group of undersea systems known as unmanned underwater vehicles, a classification that includes non-autonomous remotely operated underwater vehicles...

  • Bathymetry
    Bathymetry
    Bathymetry is the study of underwater depth of lake or ocean floors. In other words, bathymetry is the underwater equivalent to hypsometry. The name comes from Greek βαθύς , "deep", and μέτρον , "measure"...

  • Deep sea
    Deep sea
    The deep sea, or deep layer, is the lowest layer in the ocean, existing below the thermocline and above the seabed, at a depth of 1000 fathoms or more. Little or no light penetrates this part of the ocean and most of the organisms that live there rely for subsistence on falling organic matter...

  • Deep Submergence Vehicle
    Deep Submergence Vehicle
    A Deep Sea Submergence Vehicle is a deep diving manned submarine that is self-propelled. The term DSV is generally one used by the United States Navy, though several navies operate vehicles that can be accurately described as DSVs...

  • Diving chamber
    Diving chamber
    A diving chamber has two main functions:* as a simpler form of submersible vessel to take divers underwater and to provide a temporary base and retrieval system in the depths;...

  • Timeline of diving technology

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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