Oceanic trenches are prominent, long, narrow topographic depressions of the ocean floor . They are typically 50 to 100 kilometers (30 to 60 mi) wide and 3 to 4 km (1.9 to 2.5 mi) below the level of the surrounding oceanic floor, but can be thousands of kilometers in length. There are about 50,000 km (31,000 mi) of oceanic trenches worldwide, mostly around the Pacific Ocean , but also in the eastern Indian Ocean and a few other locations. The greatest ocean depth measured is in the Challenger Deep of the Mariana Trench , at a depth of 10,994 m (36,070 ft) below sea level .
187-531: The Mariana Trench is an oceanic trench located in the western Pacific Ocean , about 200 kilometres (124 mi) east of the Mariana Islands ; it is the deepest oceanic trench on Earth. It is crescent-shaped and measures about 2,550 km (1,580 mi) in length and 69 km (43 mi) in width. The maximum known depth is 10,984 ± 25 metres (36,037 ± 82 ft; 6,006 ± 14 fathoms; 6.825 ± 0.016 mi) at
374-505: A trough deeper that Vitiaz 's record by 5 metres (16 ft) was detected. There is a possibility that a depth exceeding 11,000 metres (36,089 ft) with a horizontal scale less than the beam width of measurements exists in the Challenger Deep. Since each SeaBeam 2.7-degree beam width sonar ping expands to cover a circular area about 500 metres (1,640 ft) in diameter at 11,000 metres (36,089 ft) depth, dips in
561-551: A 12 kHz Precision Depth Recorder (PDR) with a single 60° beam. They mapped one, "possibly two", axial basins with a depth of 10,915 ± 20 m (35,810 ± 66 ft). Five dredges were hauled 27–31 March, all into or slightly north of the deepest depths of the western basin. Fisher noted that this survey of the Challenger Deep (western basin) had "provided nothing to support and much to refute recent claims of depths there greater than 10,915 ± 20 m (35,810 ± 66 ft)." While Fisher missed
748-613: A Kongsberg Maritime EM 122 multi-beam echosounder system coupled to positioning equipment that can determine latitude and longitude the team determined that the Challenger Deep has a maximum depth of 10,925 m (35,843 ft) at 11°19.945′N 142°12.123′E / 11.332417°N 142.202050°E / 11.332417; 142.202050 ( 11°19′57″N 142°12′07″E / 11.332417°N 142.20205°E / 11.332417; 142.20205 ), with an estimated vertical uncertainty of ±12 m (39 ft) at one standard deviation (≈ 68.3%) confidence level. The analysis of
935-399: A bending force (FPB) that supplies pressure during subduction, while the overriding plate exerts a force against the subducting plate (FTS). The slab pull force (FSP) is caused by the negative buoyancy of the plate driving the plate to greater depths. The resisting force from the surrounding mantle opposes the slab pull forces. Interactions with the 660-km discontinuity cause a deflection due to
1122-457: A brief transit of the area on Cruise #25. She returned in 1958, Cruise #27, to conduct a detailed single beam bathymetry survey involving over a dozen transects of the Deep, with an extensive examination of the western basin and a quick peek into the eastern basin. Fisher records a total of three Vityaz sounding locations on Fig.2 "Trenches" (1963), one within yards of the 142°11.5' E location, and
1309-484: A depth of 10,920 ± 5 m (35,827 ± 16 ft), located about 290 m (950 ft) southeast of the deepest site determined by the survey vessel Takuyo in 1984. The 2002 surveys of both the western and eastern basins were tight, with especially meticulous cross-gridding of the eastern basin with ten parallel tracks N–S and E–W less than 250 meters apart. On the morning of 17 October, ROV Kaikō dive #272 began and recovered over 33 hours later, with
1496-440: A depth of 10,951 m (35,928 ft) was located at approximately 23.75 nmi (44.0 km) to the east at 11°22′11″N 142°35′19″E / 11.369639°N 142.588582°E / 11.369639; 142.588582 in the eastern basin of the Challenger Deep. JAMSTEC returned Yokosuka to the Challenger Deep with cruise YK10-16, 21–28 November 2010. The chief scientist of this joint Japanese-Danish expedition
1683-627: A depth of 5,269 fathoms (9,636 metres; 31,614 feet). In 1951, under Chief Scientist Thomas Gaskell , Challenger II surveyed the trench using echo sounding , a much more precise and vastly easier way to measure depth than the sounding equipment and drag lines used in the original expedition. During this survey, the deepest part of the trench was recorded when the Challenger II measured a depth of 5,960 fathoms (10,900 metres; 35,760 feet) at 11°19′N 142°15′E / 11.317°N 142.250°E / 11.317; 142.250 , known as
1870-457: A difference in buoyancy. An increase in retrograde trench migration (slab rollback) (2–4 cm/yr) is a result of flattened slabs at the 660-km discontinuity where the slab does not penetrate into the lower mantle. This is the case for the Japan, Java and Izu–Bonin trenches. These flattened slabs are only temporarily arrested in the transition zone. The subsequent displacement into the lower mantle
2057-514: A global rate of about 3 km (1.2 sq mi) per year. A trench marks the position at which the flexed, subducting slab begins to descend beneath another lithospheric slab. Trenches are generally parallel to and about 200 km (120 mi) from a volcanic arc . Much of the fluid trapped in sediments of the subducting slab returns to the surface at the oceanic trench, producing mud volcanoes and cold seeps . These support unique biomes based on chemotrophic microorganisms. There
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#17327662746282244-492: A maximum depth of 10,030 ± 10 m (32,907 ± 33 ft), and thus established that the Challenger Deep was about 800 metres (2,600 ft) deeper than the Philippine Trench. The 1959 Stranger surveys of the Challenger Deep and of the Philippine Trench informed the U.S. Navy as to the appropriate site for Trieste 's record dive in 1960. The Proa Expedition, Leg 2 , returned Fisher to
2431-417: A maximum depth of 10,915 ± 10 m (35,810 ± 33 ft) at 11°20.0′N 142°11.8′E / 11.3333°N 142.1967°E / 11.3333; 142.1967 . Discrepancies between the geographical location (lat/long) of Stranger 's deepest depths and those from earlier expeditions ( Challenger II 1951; Vityaz 1957 and 1958) "are probably due to uncertainties in fixing
2618-421: A maximum depth of 10,920 ± 10 m (35,827 ± 33 ft) below sea level . A subsequent study revised the value to 10,935 ± 6 m (35,876 ± 20 ft) at a 95% confidence interval ). However, both the precise geographic location and depth remain ambiguous, with contemporary measurements ranging from 10,903 to 11,009 m (35,771 to 36,119 ft). The depression
2805-463: A mile. The titanium-shelled hydrophone was designed to withstand the immense pressure 7 miles (37,000 ft; 6,200 fathoms; 11,000 m) under. Although researchers were unable to retrieve the hydrophone until November, the data capacity was full within the first 23 days. After months of analyzing the sounds, the experts were surprised to pick up natural sounds like earthquakes , typhoons , baleen whales , and machine-made sounds such as boats. Due to
2992-561: A new species of snailfish from the Northern slope of the Challenger Deep at 7,581 metres (24,872 ft), newly designated Pseudoliparis swirei . They also placed four or more CTD casts into the central and eastern basins of the Challenger Deep, as part of the World Ocean Circulation Experiment (WOCE). Tokyo University of Marine Science and Technology dispatched the research vessel Shinyo Maru to
3179-443: A newly developed gravimeter that could measure gravity from aboard a submarine. He proposed the tectogene hypothesis to explain the belts of negative gravity anomalies that were found near island arcs. According to this hypothesis, the belts were zones of downwelling of light crustal rock arising from subcrustal convection currents. The tectogene hypothesis was further developed by Griggs in 1939, using an analogue model based on
3366-464: A pair of rotating drums. Harry Hammond Hess substantially revised the theory based on his geological analysis. World War II in the Pacific led to great improvements of bathymetry, particularly in the western Pacific. In light of these new measurements, the linear nature of the deeps became clear. There was a rapid growth of deep sea research efforts, especially the widespread use of echosounders in
3553-411: A quick but thorough depth survey of the Challenger Deep, 11–13 January 1998, under chief scientist Kantaro Fujioka. Tracking largely along the trench axis of 070–250° they made five 80-km bathymetric survey tracks, spaced about 15 km apart, overlapping their SeaBeam 2112-004 (which now allowed sub-bottom profiling penetrating as much as 75 m below the bottom) while gaining gravity and magnetic data covering
3740-591: A spot was found along the Mariana Trench that had a depth similar to the Challenger Deep, possibly even deeper. It was discovered while scientists from the Hawaii Institute of Geophysics and Planetology were completing a survey around Guam ; they used a sonar mapping system towed behind the research ship to conduct the survey. This new spot was named the HMRG (Hawaii Mapping Research Group) Deep , after
3927-582: A survey of the Marianas Trench between Guam and Ulithi atoll, using seismic-sized bomb-soundings and recorded a maximum depth of 5,663 fathoms (33,978 ft; 10,356 m). The depth was beyond Challenger II 's echo sounder capability to verify, so they resorted to using a taut wire with "140 lbs of scrap iron", and documented a depth of 5,899 fathoms (35,394 ft; 10,788 m). The Senior Scientist aboard Challenger II , Thomas Gaskell , recalled: [I]t took from ten past five in
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#17327662746284114-733: A third at 11°20.0′N 142°07′E / 11.3333°N 142.117°E / 11.3333; 142.117 , all with 11,034 ± 50 m (36,201 ± 164 ft) depth. The depths were considered statistical outliers , and a depth greater than 11,000 m has never been proven. Taira reports that if Vityaz 's depth was corrected with the same methodology used by the Japanese RV Hakuho Maru expedition of December 1992, it would be presented as 10,983 ± 50 m (36,033 ± 164 ft), as opposed to modern depths from multibeam echosounder systems greater than 10,900 metres (35,800 ft) with
4301-523: A transverse line across the Challenger Deep on 1 December 1992. The center CTD was located at 11°22.78′N 142°34.95′E / 11.37967°N 142.58250°E / 11.37967; 142.58250 , in the eastern basin, at 10,989 metres (36,053 ft) by the SeaBeam depth recorder and 10,884 metres (35,709 ft) by the CTD. The other two CTDs were cast 19.9 km to the north and 16.1 km to
4488-537: A trench, sedimentation also takes place from landslides on the tectonically steepened inner slope, often driven by megathrust earthquakes . The Reloca Slide of the central Chile trench is an example of this process. Convergent margins are classified as erosive or accretionary, and this has a strong influence on the morphology of the inner slope of the trench. Erosive margins, such as the northern Peru-Chile, Tonga-Kermadec, and Mariana trenches, correspond to sediment-starved trenches. The subducting slab erodes material from
4675-490: A trip to New Zealand waters (YK13-09), with the return cruise identified as YK13-12. The project name was QUELLE2013; and the cruise title was: "In situ experimental & sampling study to understand abyssal biodiversity and biogeochemical cycles". They spent one day on the return trip at the Challenger Deep to obtain DNA/RNA on the large amphipods inhabiting the Deep ( Hirondellea gigas ). Hideki Kobayashi (Biogeos, JAMSTEC) and
4862-513: A volcanic arc) are diagnostic of convergent plate boundaries and their deeper manifestations, subduction zones . Here, two tectonic plates are drifting into each other at a rate of a few millimeters to over 10 centimeters (4 in) per year. At least one of the plates is oceanic lithosphere , which plunges under the other plate to be recycled in the Earth's mantle . Trenches are related to, but distinct from, continental collision zones, such as
5049-664: Is Fais Island (one of the outer islands of Yap ), 287 km (178 mi) southwest, and Guam , 304 km (189 mi) to the northeast. Detailed sonar mapping of the western, center and eastern basins in June 2020 by the DSSV Pressure Drop combined with manned descents revealed that they undulate with slopes and piles of rocks above a bed of pelagic ooze . This conforms with the description of Challenger Deep as consisting of an elongated seabed section with distinct sub-basins or sediment-filled pools. Over many years,
5236-426: Is a relatively small slot-shaped depression in the bottom of a considerably larger crescent-shaped oceanic trench , which itself is an unusually deep feature in the ocean floor. The Challenger Deep consists of three basins, each 6 to 10 km (3.7 to 6.2 mi ) long, 2 km (1.2 mi) wide, and over 10,850 m (35,597 ft) in depth, oriented in echelon from west to east, separated by mounds between
5423-613: Is a site chosen by researchers at Washington University in St. Louis and the Woods Hole Oceanographic Institution in 2012 for a seismic survey to investigate the subsurface water cycle . Using both ocean-bottom seismometers and hydrophones , the scientists are able to map structures as deep as 97 kilometres (318,000 ft; 53,000 fathoms; 60 miles) beneath the surface. As of 2022, 22 crewed descents and seven uncrewed descents have been achieved. The first
5610-413: Is broken by bending faults that give the outer trench slope a horst and graben topography. The formation of these bending faults is suppressed where oceanic ridges or large seamounts are subducting into the trench, but the bending faults cut right across smaller seamounts. Where the subducting slab is only thinly veneered with sediments, the outer slope will often show seafloor spreading ridges oblique to
5797-493: Is by frontal accretion, in which sediments are scraped off the downgoing plate and emplaced at the front of the accretionary prism. As the accretionary wedge grows, older sediments further from the trench become increasingly lithified , and faults and other structural features are steepened by rotation towards the trench. The other mechanism for accretionary prism growth is underplating (also known as basal accretion ) of subducted sediments, together with some oceanic crust , along
Mariana Trench - Misplaced Pages Continue
5984-476: Is caused by slab pull forces, or the destabilization of the slab from warming and broadening due to thermal diffusion. Slabs that penetrate directly into the lower mantle result in slower slab rollback rates (~1–3 cm/yr) such as the Mariana arc, Tonga arcs. As sediments are subducted at the bottom of trenches, much of their fluid content is expelled and moves back along the subduction décollement to emerge on
6171-595: Is concern that plastic debris is accumulating in trenches and threatening these communities. There are approximately 50,000 km (31,000 mi) of convergent plate margins worldwide. These are mostly located around the Pacific Ocean, but are also found in the eastern Indian Ocean , with a few shorter convergent margin segments in other parts of the Indian Ocean, in the Atlantic Ocean, and in
6358-470: Is especially important when sounding in deep water, as the resulting footprint of an acoustic pulse gets large once it reaches a distant sea floor. Further, sonar operation is affected by variations in sound speed , particularly in the vertical plane. The speed is determined by the water's bulk modulus , mass , and density . The bulk modulus is affected by temperature, pressure , and dissolved impurities (usually salinity ). In 1875, during her transit from
6545-545: Is named after the British Royal Navy survey ships HMS Challenger , whose expedition of 1872–1876 first located it, and HMS Challenger II , whose expedition of 1950–1952 established its record-setting depth. The first descent by any vehicle was by the bathyscaphe Trieste in January 1960. As of July 2022 , there were 27 people who have descended to the Challenger Deep . The Challenger Deep
6732-471: Is not available). Yayanos noted: "The lasting impression from this cruise comes from the thoughts of the revolutionary things that Seabeam data can do for deep biology." On 22 August 1988, the U.S. Navy-owned 1,000-ton research vessel Moana Wave (AGOR-22), operated by the Hawaii Institute of Geophysics (HIG), University of Hawaii , under the direction of chief scientist Robert C. Thunell from
6919-477: Is part of China's national marine research fleet but is owned by a Shanghai marine technology company. CAS' Institute of Deep-sea Science and Engineering sponsored Tansuo-1 's return to the Challenger Deep 20 January – 5 February 2017 (cruise TS03) with baited traps for the capture of fish and other macrobiology near the Challenger and Sirena Deeps. On 29 January they recovered photography and samples of
7106-602: Is reflected in the deep trenches of the western Pacific. Here the bottoms of the Marianas and the Tonga–Kermadec trenches are up to 10–11 kilometers (6.2–6.8 mi) below sea level. In the eastern Pacific, where the subducting oceanic lithosphere is much younger, the depth of the Peru-Chile trench is around 7 to 8 kilometers (4.3 to 5.0 mi). Though narrow, oceanic trenches are remarkably long and continuous, forming
7293-411: Is roughened by localized mass wasting . Cascadia has practically no bathymetric expression of the outer rise and trench, due to complete sediment filling, but the inner trench slope is complex, with many thrust ridges. These compete with canyon formation by rivers draining into the trench. Inner trench slopes of erosive margins rarely show thrust ridges. Accretionary prisms grow in two ways. The first
7480-541: Is the deepest known point of the seabed of Earth , located in the western Pacific Ocean at the southern end of the Mariana Trench , in the ocean territory of the Federated States of Micronesia . The GEBCO Gazetteer of Undersea Feature Names indicates that the feature is situated at 11°22.4′N 142°35.5′E / 11.3733°N 142.5917°E / 11.3733; 142.5917 and has
7667-494: Is the first underwater vehicle to operate autonomously at the extreme depths of the Mariana Trench. The duration of the mission, excluding diving and surfacing, was more than 3 hours. On 10 November 2020, the Chinese submersible Fendouzhe reached the bottom of the Mariana Trench at a depth of 10,909 m (35,791 ft; 5,965 fathoms). The expedition conducted in 1960 claimed to have observed, with great surprise because of
Mariana Trench - Misplaced Pages Continue
7854-677: Is the forearc basin of the Lesser Antilles subduction zone . Also not a trench is the New Caledonia trough, which is an extensional sedimentary basin related to the Tonga-Kermadec subduction zone . Additionally, the Cayman Trough, which is a pull-apart basin within a transform fault zone, is not an oceanic trench. Trenches, along with volcanic arcs and Wadati–Benioff zones (zones of earthquakes under
8041-405: Is the process where species grow larger than their shallow-water relatives. In May 2017, an unidentified type of snailfish was filmed at a depth of 8,178 metres (26,800 ft). In 2016, a research expedition looked at the chemical makeup of crustacean scavengers collected from the range of 7,841–10,250 m (25,725–33,629 ft; 4,288–5,605 fathoms) within the trench. Within these organisms,
8228-649: The Admiralty Islands in the Bismarck Archipelago to Yokohama in Japan, the three-masted sailing corvette HMS Challenger attempted to make landfall at Spanish Marianas (now Guam ), but was set to the west by "baffling winds" preventing her crew from "visiting either the Carolines or the Ladrones ." Their altered path took them over the undersea canyon which later became known as
8415-638: The Challenger Deep . In 1957, the Soviet vessel Vityaz reported a depth of 11,034 m (36,201 ft; 6,033 fathoms) at a location dubbed the Mariana Hollow . In 1962, the surface ship M.V. Spencer F. Baird recorded a maximum depth of 10,915 m (35,810 ft; 5,968 fathoms) using precision depth gauges . In 1984, the Japanese survey vessel Takuyō (拓洋) collected data from
8602-534: The Earth's mantle , the second layer of the Earth. In 1979 Japan planned to dump low-level nuclear wastes near Maug, in the Northern Marianas. However, ocean dumping of nuclear waste is prohibited by international law. Furthermore, plate subduction zones are associated with very large megathrust earthquakes , the effects of which are unpredictable for the safety of long-term disposal of nuclear wastes within
8789-498: The Himalayas . Unlike in trenches, in continental collision zones continental crust enters a subduction zone. When buoyant continental crust enters a trench, subduction comes to a halt and the area becomes a zone of continental collision. Features analogous to trenches are associated with collision zones . One such feature is the peripheral foreland basin , a sediment-filled foredeep . Examples of peripheral foreland basins include
8976-615: The Makran Trough. Some trenches are completely buried and lack bathymetric expression as in the Cascadia subduction zone , which is completely filled with sediments. Despite their appearance, in these instances the fundamental plate-tectonic structure is still an oceanic trench. Some troughs look similar to oceanic trenches but possess other tectonic structures. One example is the Lesser Antilles Trough, which
9163-694: The Polytechnic University of Marche , Italy (UNIVPM) were investigating the dynamics in virus/ prokaryotes interactions in the Mariana Trench. From 16–19 December 2014, the Schmidt Ocean Institute 's 2,024-ton research vessel Falkor , under chief scientist Douglas Bartlett from the Scripps Institution of Oceanography, deployed four different untethered instruments into the Challenger Deep for seven total releases. Four landers were deployed on 16 December into
9350-472: The Scripps Institution of Oceanography . Data has also suggested that microbial life forms thrive within the trench. The Mariana Trench is named after the nearby Mariana Islands , which are named Las Marianas in honor of Spanish Queen Mariana of Austria . The islands are part of the island arc that is formed on an over-riding plate, called the Mariana plate (also named for the islands), on
9537-498: The University of South Carolina , transited northwesterly across the central basin of the Challenger Deep, conducting a single-beam bathymetry track by their 3.5 kHz narrow (30-degs) beam echosounder with a Precision Depth Recorder. In addition to sonar bathymetry, they took 44 gravity cores and 21 box cores of bottom sediments. The deepest echosoundings recorded were 10,656 to 10,916 metres (34,961–35,814 ft), with
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#17327662746289724-648: The floodplains of the Ganges River and the Tigris-Euphrates river system . Trenches were not clearly defined until the late 1940s and 1950s. The bathymetry of the ocean was poorly known prior to the Challenger expedition of 1872–1876, which took 492 soundings of the deep ocean. At station #225, the expedition discovered Challenger Deep , now known to be the southern end of the Mariana Trench . The laying of transatlantic telegraph cables on
9911-473: The hadopelagic ecosystem . 11°21′N 142°12′E / 11.350°N 142.200°E / 11.350; 142.200 Oceanic trench Oceanic trenches are a feature of the Earth's distinctive plate tectonics . They mark the locations of convergent plate boundaries , along which lithospheric plates move towards each other at rates that vary from a few millimeters to over ten centimeters per year. Oceanic lithosphere moves into trenches at
10098-444: The shear stresses at the base of the overriding plate. As slab rollback velocities increase, circular mantle flow velocities also increase, accelerating extension rates. Extension rates are altered when the slab interacts with the discontinuities within the mantle at 410 km and 660 km depth. Slabs can either penetrate directly into the lower mantle , or can be retarded due to the phase transition at 660 km depth creating
10285-526: The "11-K camera system" lander for sediment cores and water samples to "Station C" at the deepest depth, i.e. 11°22.19429′N 142°25.7574′E / 11.36990483°N 142.4292900°E / 11.36990483; 142.4292900 , at 10,903 metres (35,771 ft). The other stations were investigated with the "Multi-core" lander, both to the backarc northward, and to the Pacific Plate southward. The 11,000-meter capable crawler-driven ROV ABIMSO
10472-606: The "Marianas Deep" (sic) in October 1951. Using their newly improved echo sounder, they ran survey lines at right angles to the axis of the trench and discovered "a considerable area of a depth greater than 5,900 fathoms (35,400 ft; 10,790 m)" – later identified as the Challenger Deep's western basin. The greatest depth recorded was 5,940 fathoms (35,640 ft; 10,863 m), at 11°19′N 142°15′E / 11.317°N 142.250°E / 11.317; 142.250 . Navigational accuracy of several hundred meters
10659-483: The 142°30.00' longitude line, about 30 nmi east of the earlier DY37II cruise survey (see Xiangyanghong 09 above). In November 2016 sonar mapping of the Challenger Deep area was conducted by the Royal Netherlands Institute for Sea Research (NIOZ)/ GEOMAR Helmholtz Centre for Ocean Research Kiel aboard the 8,554-ton Deep Ocean Research Vessel Sonne . The results were reported in 2017. Using
10846-410: The 16-beam Seabeam "Classic". This allowed chief scientist Yayanos an opportunity to transit the Challenger Deep with the most modern depth-sounding equipment available. During the pre-midnight hours of 21 April 1986, the multibeam echosounder produced a map of the Challenger Deep bottom with a swath of about 5–7 miles wide. The maximum depth recorded was 10,804 metres (35,446 ft) (location of depth
11033-479: The 1950s and 1960s. These efforts confirmed the morphological utility of the term "trench." Important trenches were identified, sampled, and mapped via sonar. The early phase of trench exploration reached its peak with the 1960 descent of the Bathyscaphe Trieste to the bottom of the Challenger Deep. Following Robert S. Dietz ' and Harry Hess ' promulgation of the seafloor spreading hypothesis in
11220-429: The 1998–1999 surveys include the first recognition that the Challenger Deep consists of three "right-stepping en echelon individual basins bounded by the 10,500 metres (34,400 ft) depth contour line. The size of [each of] the deeps are almost identical, 14–20 km long, 4 km wide". They concluded with the proposal "that these three individual elongated deeps constitute the 'Challenger Deep', and [we] identify them as
11407-588: The 1999 Kairei cruise shows that the greatest depths in the eastern, central, and western depressions are 10,920 ± 10 m (35,827 ± 33 ft), 10,894 ± 14 m (35,741 ± 46 ft), and 10,907 ± 13 m (35,784 ± 43 ft), respectively, which supports the results of the previous survey. In 2002 Kairei revisited the Challenger Deep 16–25 October 2002, as cruise KR02-13 (a cooperative Japan-US-South Korea research program) with chief scientist Jun Hashimoto in charge; again with Kazuyoshi Hirata managing
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#173276627462811594-560: The 37th China Cruise Dayang (DY37II) sponsored by the National Deep Sea Center, Qingdao and the Institute of Deep-Sea Science and Engineering, Chinese Academy of Sciences (Sanya, Hainan), to the Challenger Deep western basin area (11°22' N, 142°25' E) 4 June – 12 July 2016. As the mother ship for China's manned deep submersible Jiaolong , the expedition carried out an exploration of the Challenger Deep to investigate
11781-481: The CAS 3,300-ton research vessel Shiyan 3 deployed 33 broadband seismometers onto both the backarc northwest of the Challenger Deep, and onto the near southern Pacific Plate to the southeast, at depths of up to 8,137 m (26,696 ft). This cruise was part of a $ 12 million Chinese-U.S. initiative, led by co-leader Jian Lin of the Woods Hole Oceanographic Institution ; a 5-year effort (2017–2021) to image in fine detail
11968-583: The Challenger Deep from her home port of Sanya, Hainan Island. On 12 July 2016, the ROV Haidou-1 dived to a depth of 10,767 metres (35,325 ft) in the Challenger Deep area. They also cast a free-drop lander, 9,000 metres (29,528 ft) rated free-drop ocean-floor seismic instruments (deployed to 7,731 metres (25,364 ft)), obtained sediment core samples, and collected over 2000 biological samples from depths ranging from 5,000 to 10,000 metres (16,404–32,808 ft). The Tansuo 01 operated along
12155-504: The Challenger Deep in 12 km (7.5 mi) sidesteps, covering more than 90 nmi (166.7 km) north into the backarc with overlapping swaths from their SeaBeam 2000 12 kHz multi-beam echosounder and MR1 towed system. They also gathered magnetic and gravity information, but no seismic data. Their primary survey instrument was the MR1 towed sonar, a shallow-towed 11/12 kHz bathymetric sidescan sonar developed and operated by
12342-507: The Challenger Deep on 12–13 April 1962 aboard the Scripps research vessel Spencer F. Baird (formerly the steel-hulled US Army large tug LT-581 ) and employed a Precision Depth Recorder (PDR) to verify the extreme depths previously reported. They recorded a maximum depth of 10,915 metres (35,810 ft) (location not available). Additionally, at location "H-4" in the Challenger Deep, the expedition cast three taut-wire soundings: on 12 April,
12529-563: The Challenger Deep with multibeam ensonification. Under chief scientist Hideo Nishida, they used CTD temperature and salinity data from the top 4,500 metres (14,764 ft) of the water column to correct depth measurements, and later conferred with Scripps Institution of Oceanography (including Fisher), and other GEBCO experts to confirm their depth correction methodology. They employed a combination of NAVSAT , LORAN-C and OMEGA systems for geodetic positioning with accuracy better than 400 metres (1,300 ft). The deepest location recorded
12716-557: The Challenger Deep, mainly with biological objectives. "Echo soundings were carried out primarily with a 3.5 kHz single-beam system, with a 12 kHz echosounder operated in addition some of the time" (the 12 kHz system was activated for testing on 16 January). A benthic lander was put into the western basin ( 11°19.7′N 142°09.3′E / 11.3283°N 142.1550°E / 11.3283; 142.1550 ) on 13 January, bottoming at 10,663 metres (34,984 ft) and recovered 50 hours later in damaged condition. Quickly repaired, it
12903-521: The Challenger Deep. Depth soundings were taken by Baillie-weighted marked rope, and geographical locations were determined by celestial navigation (to an estimated accuracy of two nautical miles). One of their samples was taken within fifteen miles of the deepest spot in all of Earth's oceans. On 23 March 1875, at sample station number #225, HMS Challenger recorded the bottom at 4,475 fathoms (26,850 ft ; 8,184 m ) deep, (the deepest sounding of her three-plus-year eastward circumnavigation of
13090-404: The Challenger Deep. A 6-hour descent into the western basin anchored the array at 10,854.7 ± 8.9 m (35,613 ± 29 ft) of water depth, at 11°20.127′N 142°12.0233′E / 11.335450°N 142.2003883°E / 11.335450; 142.2003883 , about 1 km northeast of Sumner 's deepest depth, recorded in 2010. After 16 weeks, the moored array
13277-565: The Chilean trench. The north Chile portion of the trench, which lies along the Atacama Desert with its very slow rate of weathering, is sediment-starved, with from 20 to a few hundred meters of sediments on the trench floor. The tectonic morphology of this trench segment is fully exposed on the ocean bottom. The central Chile segment of the trench is moderately sedimented, with sediments onlapping onto pelagic sediments or ocean basement of
13464-652: The Cook Expedition, Leg 6 with chief scientist Patricia Fryer of the University of Hawaii from Guam on 10 February 2001 to the Challenger Deep for a survey titled "Subduction Factory Studies in the Southern Mariana", including HMR-1 sonar mapping, magnetics, gravity measurements, and dredging in the Mariana arc region. They covered all three basins, then tracked 120-nautical-mile-long (222.2 km) lines of bathymetry East-West, stepping northward from
13651-526: The Deep from east to west, collecting single beam bathymetry, magnetic and gravity measurements, and employed the air guns along the trench axis, and well into the backarc and forearc , from 13 to 15 March 1976. Thence they proceeded south to the Ontong Java Plateau . All three deep basins of the Challenger Deep were covered, but Kana Keoki recorded a maximum depth of 7,800 m (25,591 ft). Seismic information developed from this survey
13838-628: The Earth's third deepest site (the Sirena Deep only 150 nautical miles east of the Challenger Deep), which would remain undiscovered for another 122 years. Seventy-five years later, the 1,140-ton British survey vessel HMS Challenger II , on her three-year westward circumnavigation of Earth, investigated the extreme depths southwest of Guam reported in 1875 by her predecessor, HMS Challenger . On her southbound track from Japan to New Zealand (May–July 1951), Challenger II conducted
14025-466: The Earth) at 11°24′N 143°16′E / 11.400°N 143.267°E / 11.400; 143.267 – and confirmed it with a second sounding at the same location. The serendipitous discovery of Earth's deepest depression by history's first major scientific expedition devoted entirely to the emerging science of oceanography , was incredibly good fortune, and especially notable when compared to
14212-515: The East, Central and West Deep. The deepest depth we obtained during the swath mapping is 10,938 metres (35,886 ft) in the West Deep (11°20.34' N, 142°13.20 E)." The depth was "obtained during swath mapping ... confirmed in both N–S and E-W swaths." Speed of sound corrections were from XBT to 1,800 metres (5,900 ft), and CTD below 1,800 metres (5,900 ft). The cross track survey of
14399-574: The Guam-based 1,930-ton US Coast Guard Cutter Sequoia (WLB 215) hosted a team of researchers, under chief scientist Robert P. Dziak, from the NOAA Pacific Marine Environmental Laboratory (PMEL), the University of Washington , and Oregon State University, in deploying PMEL's "Full-Ocean Depth Mooring", a 45-meter-long moored deep-ocean hydrophone and pressure sensor array into the western basin of
14586-473: The HMRG Deep/Sirena Deep at 10,714 ± 20 m (35,151 ± 66 ft) are centered at/near 12°03.94′N 142°34.866′E / 12.06567°N 142.581100°E / 12.06567; 142.581100 , approximately 2.65 km from Fisher's 25 March 1975 10,015 metres (32,858 ft) dredge haul. On Scripps Institution of Oceanography's INDOPAC Expedition Leg 3 ,
14773-646: The Hawaii Mapping Research Group (HMRG), a research and operational group within University of Hawaii's School of Ocean and Earth Science and Technology (SOEST) and the Hawaii Institute of Geophysics and Planetology (HIGP). The MR1 is full-ocean-depth capable, providing both bathymetry and sidescan data. Leg 7 of the Cook Expedition continued the MR-1 survey of the Mariana Trench backarc from 4 March to 12 April 2001 under chief scientist Sherman Bloomer of Oregon State University . In May/June 2009,
14960-447: The Mariana Trench from 20 January to 5 February 2017 with baited traps for the capture of fish and other macrobiology near the Challenger and Sirena Deeps. On 29 January they recovered photography and samples of a new species of snailfish from the Northern slope of the Challenger Deep at 7,581 metres (24,872 ft), which has been newly designated Pseudoliparis swirei . Water samples were collected at Challenger Deep from 11 layers of
15147-471: The Mariana Trench using a narrow, multi-beam echo sounder; it reported a maximum depth of 10,924 metres (35,840 ft), also reported as 10,920 ± 10 m (35,827 ± 33 ft; 5,971.1 ± 5.5 fathoms). Remotely Operated Vehicle KAIKO reached the deepest area of the Mariana Trench and made the deepest diving record of 10,911 m (35,797 ft; 5,966 fathoms) on 24 March 1995. During surveys carried out between 1997 and 2001,
15334-566: The Mediterranean. They are found on the oceanward side of island arcs and Andean-type orogens . Globally, there are over 50 major ocean trenches covering an area of 1.9 million km or about 0.5% of the oceans. Trenches are geomorphologically distinct from troughs . Troughs are elongated depressions of the sea floor with steep sides and flat bottoms, while trenches are characterized by a V-shaped profile. Trenches that are partially infilled are sometimes described as troughs, for example
15521-898: The NOAA accepted maximum of 10,995 ± 10 m (36,073 ± 33 ft) in the western basin. The first definitive verification of both the depth and location of the Challenger Deep (western basin) was determined by Dr. R. L. Fisher from the Scripps Institution of Oceanography , aboard the 325-ton research vessel Stranger . Using explosive soundings, they recorded 10,850 ± 20 m (35,597 ± 66 ft) at/near 11°18′N 142°14′E / 11.300°N 142.233°E / 11.300; 142.233 in July 1959. Stranger used celestial and LORAN-C for navigation. LORAN-C navigation provided geographical accuracy of 460 m (1,509 ft) or better. According to another source RV Stranger using bomb-sounding surveyed
15708-606: The ROV Kaikō team. On this survey, the size of each of the three basins was refined to 6–10 km long by about 2 km wide and in excess of 10,850 m (35,597 ft) deep. In marked contrast to the Kairei surveys of 1998 and 1999, the detailed survey in 2002 determined that the deepest point in the Challenger Deep is located in the eastern basin around 11°22.260′N 142°35.589′E / 11.371000°N 142.593150°E / 11.371000; 142.593150 , with
15895-580: The ROV working at the bottom of the western basin for 26 hours (vicinity of 11°20.148' N, 142°11.774 E at 10,893 m (35,738 ft)). Five Kaikō dives followed on a daily basis into the same area to service benthic landers and other scientific equipment, with dive #277 recovered on 25 October. Traps brought up large numbers of amphipods (sea fleas), and cameras recorded holothurians ( sea cucumbers ), White polychaetes (bristle worms), tube worms, and other biological species. During its 1998, 1999 surveys, Kairei
16082-562: The US Navy-owned 3,064-ton twin-hulled research vessel Kilo Moana (T-AGOR 26) was sent to the Challenger Deep area to conduct research. Kilo Moana is civilian-crewed and operated by SOEST. It is equipped with two multibeam echosounders with sub-bottom profiler add-ons (the 191-beam 12 kHz Kongsberg Simrad EM120 with SBP-1200, capable of accuracies of 0.2–0.5% of water depth across the entire swath), gravimeter , and magnetometer . The EM-120 uses 1 by 1 degree sonar-emissions at
16269-747: The annual American Geophysical Union fall meeting. Using a Kongsberg Maritime EM 122 multi-beam echosounder system coupled to positioning equipment that can determine latitude and longitude up to 50 cm (20 in) accuracy, from thousands of individual soundings around the deepest part the CCOM/JHC team preliminary determined that the Challenger Deep has a maximum depth of 10,994 m (36,070 ft) at 11°19′35″N 142°11′14″E / 11.326344°N 142.187248°E / 11.326344; 142.187248 , with an estimated vertical uncertainty of ±40 m (131 ft) at two standard deviations (i.e. ≈ 95.4%) confidence level. A secondary deep with
16456-464: The application of differing sound velocity profiles, which are essential for accurate depth determination. Sonne used CTD casts about 1.6 km west of the deepest sounding to near the bottom of the Challenger Deep that were used for sound velocity profile calibration and optimization. Likewise, the impact of using different projections, datum and ellipsoids during data acquisition can cause positional discrepancies between surveys. In December 2016,
16643-479: The area of the Southeast Pacific, there have been several rollback events resulting in the formation of numerous back-arc basins. Interactions with the mantle discontinuities play a significant role in slab rollback. Stagnation at the 660-km discontinuity causes retrograde slab motion due to the suction forces acting at the surface. Slab rollback induces mantle return flow, which causes extension from
16830-406: The basins 200 to 300 m (660 to 980 ft) higher. The three basins feature extends about 48 km (30 mi) west to east if measured at the 10,650 m (34,941 ft) isobath . Both the western and eastern basins have recorded depths (by sonar bathymetry) in excess of 10,920 m (35,827 ft), while the center basin is slightly less deep. The closest land to the Challenger Deep
17017-533: The bottom of the Mariana Trench in the submersible vessel Deepsea Challenger , diving to a depth of 10,908 m (35,787 ft; 5,965 fathoms). In July 2015, members of the National Oceanic and Atmospheric Administration, Oregon State University, and the Coast Guard submerged a hydrophone into the deepest part of the Mariana Trench, the Challenger Deep, never having previously deployed one past
17204-410: The bottom of the trench. That year, Scientific American also reported that carbon-14 from nuclear bomb testing has been found in the bodies of aquatic animals found in the trench. Like other oceanic trenches, the Mariana Trench has been proposed as a site for nuclear waste disposal in the hope that tectonic plate subduction occurring at the site might eventually push the nuclear waste deep into
17391-466: The bottom that are less than that size would be difficult to detect from a sonar-emitting platform seven miles above. For most of 1995 and into 1996, the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) employed the 4,439-ton Research Vessel Yokosuka to conduct the testing and workup of the 11,000-meter remotely-operated vehicle (ROV) Kaikō , and the 6,500 meter ROV Shinkai. It
17578-414: The bottom, they recovered some 90 individual Hirondellea gigas . JAMSTEC deployed Kairei to the Challenger Deep again 11–17 January 2014, under the leadership of chief scientist Takuro Nunora. The cruise identifier was KR14-01, titled: "Trench biosphere expedition for the Challenger Deep, Mariana Trench". The expedition sampled at six stations transecting the central basin, with only two deployments of
17765-450: The bottom. In the first successful retrieval of a live animal from the Challenger Deep, on 21 November 1980 in the western basin at 11°18.7′N 142°11.6′E / 11.3117°N 142.1933°E / 11.3117; 142.1933 , Yayanos recovered a live amphipod from about 10,900 meters depth with a pressurized trap. Once again, other than a brief look into the eastern basin, all bathymetric and biological investigations were into
17952-406: The buoyancy at the phase transition (F660). The unique interplay of these forces is what generates slab rollback. When the deep slab section obstructs the down-going motion of the shallow slab section, slab rollback occurs. The subducting slab undergoes backward sinking due to the negative buoyancy forces causing a retrogradation of the trench hinge along the surface. Upwelling of the mantle around
18139-459: The central basin at a depth of 10,285 metres (33,743 ft). The benthic lander was not recovered and may remain on the bottom in the vicinity of 11°20.1′N 142°25.2′E / 11.3350°N 142.4200°E / 11.3350; 142.4200 . Free traps and pressure-retaining traps were put down at eight locations from 13 to 19 January into the western basin, at depths ranging from 7,353 to 10,715 metres (24,124–35,154 ft). Both
18326-511: The central basin, near where Trieste dived in 1960 (vicinity 11°18.5′N 142°15.5′E / 11.3083°N 142.2583°E / 11.3083; 142.2583 , and where Challenger II , in 1950, recorded 10,863 ± 35 m (35,640 ± 115 ft). At the far western end of the western basin (about 142°11'E), the Stranger recorded 10,850 ± 20 m (35,597 ± 66 ft), some 6 km south of
18513-429: The central basin. On 13 April, the final cast recorded 5,297 fathoms (corrected for wire angle) 9,687 metres (31,781 ft) at 11°17.5′N 142°11′E / 11.2917°N 142.183°E / 11.2917; 142.183 (the western basin). They were chased off by a hurricane after only two days on-site. Once again, Fisher entirely missed the eastern basin of the Challenger Deep, which later proved to contain
18700-417: The central basin: the baited video-equipped lander Leggo for biologics; the lander ARI to 11°21.5809′N 142°27.2969′E / 11.3596817°N 142.4549483°E / 11.3596817; 142.4549483 for water chemistry; and the probes Deep Sound 3 and Deep Sound 2 . Both Deep Sound probes recorded acoustics floating at 9,000 metres (29,528 ft) depth, until Deep Sound 3 imploded at
18887-648: The chief scientist, Dr. Joseph L. Reid, and oceanographer Arnold W. Mantyla made a hydrocast of a free vehicle (a special-purpose benthic lander (or "baited camera") for measurements of water temperature and salinity) on 27 May 1976 into the western basin of the Challenger Deep, "Station 21", at 11°19.9′N 142°10.8′E / 11.3317°N 142.1800°E / 11.3317; 142.1800 at about 10,840 metres (35,560 ft) depth. On INDOPAC Expedition Leg 9 , under chief scientist A. Aristides Yayanos, Thomas Washington spent nine days from 13–21 January 1977 conducting an extensive and detailed investigation of
19074-508: The class of monothalamea , were observed. Monothalamea are noteworthy for their size, their extreme abundance on the seafloor, and their role as hosts for a variety of organisms. In December 2014, a new species of snailfish was discovered at a depth of 8,145 m (26,722 ft; 4,454 fathoms), breaking the previous record for the deepest living fish seen on video. During the 2014 expedition, several new species were filmed, including huge amphipods known as supergiants. Deep-sea gigantism
19261-432: The corrected depth was 10,989 metres (36,053 ft), and at 11°22.0′N 142°34.0′E / 11.3667°N 142.5667°E / 11.3667; 142.5667 the depth was 10,927 metres (35,850 ft); both in the eastern basin. This may demonstrate that the basins might not be flat sedimentary pools but rather undulate with a difference of 50 metres (160 ft) or more. Taira revealed, "We considered that
19448-549: The cruise, Jiaolong regularly deployed gas-tight samplers to collect water near the sea bottom. In a test of navigational proficiency, Jiaolong used an Ultra-Short Base Line (USBL) positioning system at a depth more than 6,600 metres (21,654 ft) to retrieve sampling bottles. From 22 June to 12 August 2016 (cruises 2016S1 and 2016S2), the Chinese Academy of Sciences' 6,250-ton submersible support ship Tansuo 1 (meaning: to explore) on her maiden voyage deployed to
19635-559: The deepest depths. The Scripps Institution of Oceanography deployed the 1,490-ton Navy-owned, civilian-crewed research vessel Thomas Washington (AGOR-10) to the Mariana Trench on several expeditions from 1975 to 1986. The first of these was the Eurydice Expedition, Leg 8 which brought Fisher back to the Challenger Deep's western basin from 28–31 March 1975. Thomas Washington established geodetic positioning by ( SATNAV ) with Autolog Gyro and EM Log. Bathymetrics were by
19822-412: The density of water is increased by 4.96%. The temperature at the bottom is 1 to 4 °C (34 to 39 °F). In 2009, the Mariana Trench was established as a US National Monument , Mariana Trench Marine National Monument . One-celled organisms called monothalamea have been found in the trench at a record depth of 10.6 km (35,000 ft; 6.6 mi) below the sea surface by researchers from
20009-486: The depth of 8,620 metres (28,281 ft) (about 2,200 metres (7,218 ft) above the bottom) at 11°21.99′N 142°27.2484′E / 11.36650°N 142.4541400°E / 11.36650; 142.4541400 . The Deep Sound 2 recorded the implosion of Deep Sound 3 , providing a unique recording of an implosion within the Challenger Deep depression. In addition to the loss of the Deep Sound 3 by implosion,
20196-414: The discovery of the deepest basin of the world's oceans. In August 1957, the Soviet 3,248-ton Vernadsky Institute of Geochemistry research vessel Vityaz recorded a maximum depth of 11,034 ± 50 m (36,201 ± 164 ft) at 11°20.9′N 142°11.5′E / 11.3483°N 142.1917°E / 11.3483; 142.1917 in the western basin of the Challenger Deep during
20383-405: The early 1960s and the plate tectonic revolution in the late 1960s, the oceanic trench became an important concept in plate tectonic theory. Oceanic trenches are 50 to 100 kilometers (30 to 60 mi) wide and have an asymmetric V-shape, with the steeper slope (8 to 20 degrees) on the inner (overriding) side of the trench and the gentler slope (around 5 degrees) on the outer (subducting) side of
20570-442: The eastern basin again was missed by this expedition. From 20 to 30 November 1980, Thomas Washington was on site at the western basin of the Challenger Deep, as part of Rama Expedition Leg 7 , again with chief-scientist Dr. A. A. Yayanos. Yayanos directed Thomas Washington in arguably the most extensive and wide-ranging of all single-beam bathymetric examinations of the Challenger Deep ever undertaken, with dozens of transits of
20757-438: The eastern basin of the Challenger Deep (for the third time), he did report a deep depression about 150 nautical miles east of the western basin. The 25 March dredge haul at 12°03.72′N 142°33.42′E / 12.06200°N 142.55700°E / 12.06200; 142.55700 encountered 10,015 metres (32,858 ft), which pre-shadowed by 22 years the discovery of HMRG Deep/ Sirena Deep in 1997. The deepest waters of
20944-587: The entire Challenger Deep: western, central, and eastern basins. Kairei returned in May 1998, cruise KR98-05, with ROV Kaikō , under the direction of chief scientist Jun Hashimoto with both geophysical and biological goals. Their bathymetric survey from 14–26 May was the most intensive and thorough depth and seismic survey of the Challenger Deep performed to date. Each evening, Kaikō deployed for about four hours of bottom time for biological-related sampling, plus about seven hours of vertical transit time. When Kaikō
21131-563: The entire swath (implying that the depth figure is accurate to ± 22 metres (72 ft; 12 fathoms)). In 2011, it was announced at the American Geophysical Union Fall Meeting that a US Navy hydrographic ship equipped with a multibeam echosounder conducted a survey which mapped the entire trench to 100 m (330 ft; 55 fathoms) resolution. The mapping revealed the existence of four rocky outcrops thought to be former seamounts . The Mariana Trench
21318-480: The evening until twenty to seven, that is an hour and a half, for the iron weight to fall to the sea-bottom. It was almost dark by the time the weight struck, but great excitement greeted the reading... In New Zealand, the Challenger II team gained the assistance of the Royal New Zealand Dockyard, "who managed to boost the echo sounder to record at the greatest depths". They returned to
21505-640: The exhumation of ophiolites . Slab rollback is not always a continuous process suggesting an episodic nature. The episodic nature of the rollback is explained by a change in the density of the subducting plate, such as the arrival of buoyant lithosphere (a continent, arc, ridge, or plateau), a change in the subduction dynamics, or a change in the plate kinematics. The age of the subducting plates does not have any effect on slab rollback. Nearby continental collisions have an effect on slab rollback. Continental collisions induce mantle flow and extrusion of mantle material, which causes stretching and arc-trench rollback. In
21692-463: The first cast was to 5,078 fathoms (corrected for wire angle) 9,287 metres (30,469 ft) at 11°23′N 142°19.5′E / 11.383°N 142.3250°E / 11.383; 142.3250 in the central basin (Up until 1965, US research vessels recorded soundings in fathoms). The second cast, also on 12 April, was to 5,000 fathoms at 11°20.5′N 142°22.5′E / 11.3417°N 142.3750°E / 11.3417; 142.3750 in
21879-696: The first person to dive into Challenger Deep more than once. On 8 May 2020, a joint project between the Russian shipbuilders, scientific teams of the Russian Academy of Sciences with the support of the Russian Foundation for Advanced Research Projects and the Pacific Fleet submerged the autonomous underwater vehicle Vityaz-D to the bottom of the Mariana Trench at a depth of 10,028 m (32,900 ft; 5,483 fathoms). Vityaz-D
22066-433: The free traps and the pressure-retaining traps brought up good sample amphipods for study. While the ship briefly visited the area of the eastern basin, the expedition did not recognize it as potentially the deepest of the three Challenger Deep basins. Thomas Washington returned briefly to the Challenger Deep on 17–19 October 1978 during Mariana Expedition Leg 5 under chief scientist James W. Hawkins. The ship tracked to
22253-424: The geological, biological, and chemical characteristics of the hadal zone . The diving area for this leg was on the southern slope of the Challenger Deep, at depths from about 6,300 to 8,300 metres (20,669 to 27,231 ft). The submersible completed nine piloted dives on the northern backarc and south area ( Pacific plate ) of the Challenger Deep to depths from 5,500 to 6,700 metres (18,045 to 21,982 ft). During
22440-404: The greatest depth at 11°22′N 142°25′E in the central basin. This was the first indication that all three basins contained depths in excess of 10,900 metres (35,800 ft). The 3,987-ton Japanese research vessel Hakuhō Maru , an Ocean Research Institute – University of Tokyo sponsored ship, on cruise KH-92-5 cast three Sea-Bird SBE-9 ultra-deep CTD (conductivity-temperature-depth) profilers in
22627-453: The greatest depth was at 11°20.0′N 142°11.8′E / 11.3333°N 142.1967°E / 11.3333; 142.1967 . All of the 10,900-plus m recordings were in the western basin. The 10,455 metres (34,301 ft) depth was furthest east at 142°26.4' E (in the central basin), about 17 km west of the eastern basin. Again, focused efforts on the known areas of extreme depths (the western and central basins) were so tight that
22814-424: The greatest depths in the eastern, central, and western depressions are 10,922 ± 74 m (35,833 ± 243 ft), 10,898 ± 62 m (35,755 ± 203 ft), and 10,908 ± 36 m (35,787 ± 118 ft), respectively, making the eastern depression the deepest of the three. In 1999, Kairei revisited the Challenger Deep during cruise KR99-06. The results of
23001-495: The grid point has an uncertainty of ±50 to 100 m (164 to 328 ft), depending on along-track or across-track direction. This depth (59 m (194 ft)) and position (about 410 m (1,345 ft) to the northeast) measurements differ significantly from the deepest point determined by the Gardner et al. (2014) study. The observed depth discrepancy with the 2010 sonar mapping and Gardner et al 2014 study are related to
23188-568: The group of scientists who discovered it. On 1 June 2009, mapping aboard the RV ; Kilo Moana (mothership of the Nereus vehicle), indicated a spot with a depth of 10,971 m (35,994 ft; 5,999 fathoms). The sonar mapping of the Challenger Deep was possible by its Simrad EM120 sonar multibeam bathymetry system for deep water. The sonar system uses phase and amplitude bottom detection, with an accuracy of better than 0.2% of water depth across
23375-416: The high pressure, large creatures living at the bottom, such as a flatfish about 30 cm (12 in) long, and shrimp . According to Piccard, "The bottom appeared light and clear, a waste of firm diatomaceous ooze". Many marine biologists are now skeptical of the supposed sighting of the flatfish, and it is suggested that the creature may instead have been a sea cucumber . During the second expedition,
23562-485: The higher-riding (and younger) Mariana plate. The deepest area at the plate boundary is the Mariana Trench proper. The movement of the Pacific and Mariana plates is also indirectly responsible for the formation of the Mariana Islands . These volcanic islands are caused by flux melting of the upper mantle due to the release of water that is trapped in minerals of the subducted portion of the Pacific plate . The trench
23749-539: The horst and graben ridges. Trench morphology is strongly modified by the amount of sedimentation in the trench. This varies from practically no sedimentation, as in the Tonga-Kermadec trench, to completely filled with sediments, as with the Cascadia subduction zone. Sedimentation is largely controlled by whether the trench is near a continental sediment source. The range of sedimentation is well illustrated by
23936-462: The inner slope as mud volcanoes and cold seeps . Methane clathrates and gas hydrates also accumulate in the inner slope, and there is concern that their breakdown could contribute to global warming . The fluids released at mud volcanoes and cold seeps are rich in methane and hydrogen sulfide , providing chemical energy for chemotrophic microorganisms that form the base of a unique trench biome . Cold seep communities have been identified in
24123-451: The inner trench slopes of the western Pacific (especially Japan ), South America, Barbados, the Mediterranean, Makran, and the Sunda trench. These are found at depths as great as 6,000 meters (20,000 ft). The genome of the extremophile Deinococcus from Challenger Deep has sequenced for its ecological insights and potential industrial uses. Because trenches are the lowest points in
24310-556: The lander ARI failed to respond upon receiving its instruction to drop weights, and was never recovered. On 16/17 December, Leggo was returned to the central basin baited for amphipods. On the 17th, RV Falkor relocated 17 nms eastward to the eastern basin, where they again deployed both the Leggo (baited and with its full camera load), and the Deep Sound 2 . Deep Sound 2 was programmed to drop to 9,000 metres (29,528 ft) and remain at that depth during its recording of sounds within
24497-683: The lander's mackerel bait and with sample amphipods. Falknor departed the Challenger Deep on 19 December en route the Marianas Trench Marine National Monument to the Sirena Deep. RV Falkor had both a Kongsberg EM302 and EM710 multibeam echosounder for bathymetry, and an Oceaneering C-Nav 3050 global navigation satellite system receiver, capable of calculating geodetic positioning with an accuracy better than 5 cm (2.0 in) horizontally and 15 cm (5.9 in) vertically. From 10 to 13 July 2015,
24684-403: The largest linear depressions on earth. An individual trench can be thousands of kilometers long. Most trenches are convex towards the subducting slab, which is attributed to the spherical geometry of the Earth. The trench asymmetry reflects the different physical mechanisms that determine the inner and outer slope angle. The outer slope angle of the trench is determined by the bending radius of
24871-600: The location where Vityaz recorded 11,034 ± 50 m (36,201 ± 164 ft) in 1957–1958. Fisher stated: "differences in the Vitiaz [sic] and Stranger – Challenger II depths can be attributed to the [sound] velocity correction function used". After investigating the Challenger Deep, Stranger proceeded to the Philippine Trench and transected the trench over twenty times in August 1959, finding
25058-460: The lower part of the overriding slab, reducing its volume. The edge of the slab experiences subsidence and steepening, with normal faulting. The slope is underlain by relative strong igneous and metamorphic rock, which maintains a high angle of repose. Over half of all convergent margins are erosive margins. Accretionary margins, such as the southern Peru-Chile, Cascadia, and Aleutians, are associated with moderately to heavily sedimented trenches. As
25245-479: The mission's success, the researchers announced plans to deploy a second hydrophone in 2017 for an extended period of time. Victor Vescovo achieved a new record descent to 10,928 m (35,853 ft; 5,976 fathoms) on 28 April 2019 using the DSV Limiting Factor , a Triton 36000/2 model manufactured by Florida-based Triton Submarines . He dived four times between 28 April and 5 May 2019, becoming
25432-579: The next two decades. The Yokosuka employed a 151-beam SeaBeam 2112 12 kHz multibeam echosounder, allowing search swaths 12–15 km in width at 11,000 metres (36,089 ft) depth. The depth accuracy of Yokosuka 's Seabeam was about 0.1% of water depth (i.e. ± 110 metres (361 ft) for 11,000 metres (36,089 ft) depth). The ship's dual GPS systems attained geodetic positioning within double digit meter (100 metres (328 ft) or better) accuracy. Cruise KR98-01 sent JAMSTEC's two-year-old 4,517-ton Deep Sea Research Vessel RV Kairei south for
25619-471: The northernmost Sumatra subduction zone, which is buried under 6 kilometers (3.7 mi) of sediments. Sediments are sometimes transported along the axis of an oceanic trench. The central Chile trench experiences transport of sediments from source fans along an axial channel. Similar transport of sediments has been documented in the Aleutian trench. In addition to sedimentation from rivers draining into
25806-430: The ocean floor, there is concern that plastic debris may accumulate in trenches and endanger the fragile trench biomes. Recent measurements, where the salinity and temperature of the water was measured throughout the dive, have uncertainties of about 15 m (49 ft). Older measurements may be off by hundreds of meters. (*) The five deepest trenches in the world Challenger Deep The Challenger Deep
25993-433: The researchers found extremely elevated concentrations of PCBs , a chemical toxin banned in the 1970s for its environmental harm, concentrated at all depths within the sediment of the trench. Further research has found that amphipods also ingest microplastics , with 100% of amphipods having at least one piece of synthetic material in their stomachs. In 2019, Victor Vescovo reported finding a plastic bag and candy wrappers at
26180-597: The rock layers in and around the Challenger Deep. The newly launched 4,800-ton research vessel (and mothership for the Rainbow Fish series of deep submersibles), the Zhang Jian departed Shanghai on 3 December. Their cruise was to test three new deep-sea landers, one uncrewed search submersible and the new Rainbow Fish 11,000-meter manned deep submersible, all capable of diving to 10,000 meters. From 25 to 27 December, three deep-sea landing devices descended into
26367-500: The sea surface. Each 1 degree beam width sonar ping expands to cover a circular area about 192 metres (630 ft) in diameter at 11,000 metres (36,089 ft) depth. Whilst mapping the Challenger Deep the sonar equipment indicated a maximum depth of 10,971 m (35,994 ft) at an undisclosed position. Navigation equipment includes the Applanix POS MV320 V4, rated at accuracies of 0.5–2 m. RV Kilo Moana
26554-413: The seafloor between the continents during the late 19th and early 20th centuries provided further motivation for improved bathymetry. The term trench , in its modern sense of a prominent elongated depression of the sea bottom, was first used by Johnstone in his 1923 textbook An Introduction to Oceanography . During the 1920s and 1930s, Felix Andries Vening Meinesz measured gravity over trenches using
26741-403: The search for, and investigation of, the location of the maximum depth of the world's oceans has involved many different vessels, and continues into the twenty-first century. The accuracy of determining geographical location, and the beamwidth of (multibeam) echosounder systems, limits the horizontal and vertical bathymetric sensor resolution that hydrographers can obtain from onsite data. This
26928-481: The shallow parts of the subduction decollement. The Franciscan Group of California is interpreted as an ancient accretionary prism in which underplating is recorded as tectonic mélanges and duplex structures. Frequent megathrust earthquakes modify the inner slope of the trench by triggering massive landslides. These leave semicircular landslide scarps with slopes of up to 20 degrees on the headwalls and sidewalls. Subduction of seamounts and aseismic ridges into
27115-429: The ships' positions". Stranger 's north-south zig-zag survey passed well to the east of the eastern basin southbound, and well to the west of the eastern basin northbound, thus failed to discover the eastern basin of the Challenger Deep. The maximum depth measured near longitude 142°30'E was 10,760 ± 20 m (35,302 ± 66 ft), about 10 km west of the eastern basin's deepest point. This
27302-455: The slab can create favorable conditions for the formation of a back-arc basin. Seismic tomography provides evidence for slab rollback. Results demonstrate high temperature anomalies within the mantle suggesting subducted material is present in the mantle. Ophiolites are viewed as evidence for such mechanisms as high pressure and temperature rocks are rapidly brought to the surface through the processes of slab rollback, which provides space for
27489-427: The slab subducts, sediments are "bulldozed" onto the edge of the overriding plate, producing an accretionary wedge or accretionary prism . This builds the overriding plate outwards. Because the sediments lack strength, their angle of repose is gentler than the rock making up the inner slope of erosive margin trenches. The inner slope is underlain by imbricated thrust sheets of sediments. The inner slope topography
27676-466: The slab with respect to the mantle modified by the geometry of the slab itself. The extension in the overriding plate, in response to the subsequent subhorizontal mantle flow from the displacement of the slab, can result in formation of a back-arc basin. Several forces are involved in the process of slab rollback. Two forces acting against each other at the interface of the two subducting plates exert forces against one another. The subducting plate exerts
27863-439: The sonar survey offered a 100 by 100 metres (328 ft × 328 ft) grid resolution at bottom depth, so small dips in the bottom that are less than that size would be difficult to detect from the 0.5 by 1 degree sonar-emissions at the sea surface. Each 0.5-degree beam width sonar ping expands to cover a circular area about 96 metres (315 ft) in diameter at 11,000 metres (36,089 ft) depth. The horizontal position of
28050-487: The south and west of the eastern basin, and recorded depths between 5,093 and 7,182 metres (16,709–23,563 ft). Another miss. On Mariana Expedition Leg 8 , under chief scientist Yayanos, Thomas Washington was again involved, from 12–21 December 1978, with an intensive biological study of the western and central basins of the Challenger Deep. Fourteen traps and pressure-retaining traps were put down to depths ranging from 10,455 to 10,927 metres (34,301–35,850 ft);
28237-514: The south. Hakuhō Maru was equipped with a narrow beam SeaBeam 500 multi-beam echosounder for depth determination, and had an Auto-Nav system with inputs from NAVSAT/NNSS , GPS, Doppler Log, EM log and track display, with a geodetic positioning accuracy approaching 100 metres (330 ft). When conducting CTD operations in the Challenger deep, they used the SeaBeam as a single beam depth recorder. At 11°22.6′N 142°35.0′E / 11.3767°N 142.5833°E / 11.3767; 142.5833
28424-418: The southern end of a small slot-shaped valley in its floor known as the Challenger Deep . The deepest point of the trench is more than 2 km (1.2 mi) farther from sea level than the peak of Mount Everest . At the bottom of the trench, the water column above exerts a pressure of 1,086 bar (15,750 psi), more than 1,071 times the standard atmospheric pressure at sea level. At this pressure,
28611-416: The subducting plate. This is called trench rollback or hinge retreat (also hinge rollback ) and is one explanation for the existence of back-arc basins . Forces perpendicular to the slab (the portion of the subducting plate within the mantle) are responsible for steepening of the slab and, ultimately, the movement of the hinge and trench at the surface. These forces arise from the negative buoyancy of
28798-419: The subducting slab, as determined by its elastic thickness. Since oceanic lithosphere thickens with age, the outer slope angle is ultimately determined by the age of the subducting slab. The inner slope angle is determined by the angle of repose of the overriding plate edge. This reflects frequent earthquakes along the trench that prevent oversteepening of the inner slope. As the subducting plate approaches
28985-509: The subducting slab, but the trench morphology is still clearly discernible. The southern Chile segment of the trench is fully sedimented, to the point where the outer rise and slope are no longer discernible. Other fully sedimented trenches include the Makran Trough, where sediments are up to 7.5 kilometers (4.7 mi) thick; the Cascadia subduction zone, which is completed buried by 3 to 4 kilometers (1.9 to 2.5 mi) of sediments; and
29172-434: The team deployed a benthic lander on 23 November 2013 with eleven baited traps (three bald, five covered by insulating materials, and three automatically sealed after nine hours) into the central basin of the Challenger Deep at 11°21.9082′N 142°25.7606′E / 11.3651367°N 142.4293433°E / 11.3651367; 142.4293433 , depth 10,896 metres (35,748 ft). After an eight-hour, 46-minute stay at
29359-450: The trench may increase aseismic creep and reduce the severity of earthquakes. Contrariwise, subduction of large amounts of sediments may allow ruptures along the subduction décollement to propagate for great distances to produce megathrust earthquakes. Trenches seem positionally stable over time, but scientists believe that some trenches—particularly those associated with subduction zones where two oceanic plates converge—move backward into
29546-399: The trench, it bends slightly upwards before beginning its plunge into the depths. As a result, the outer trench slope is bounded by an outer trench high . This is subtle, often only tens of meters high, and is typically located a few tens of kilometers from the trench axis. On the outer slope itself, where the plate begins to bend downwards into the trench, the upper part of the subducting slab
29733-474: The trench. The bottom of the trench marks the boundary between the subducting and overriding plates, known as the basal plate boundary shear or the subduction décollement . The depth of the trench depends on the starting depth of the oceanic lithosphere as it begins its plunge into the trench, the angle at which the slab plunges, and the amount of sedimentation in the trench. Both starting depth and subduction angle are greater for older oceanic lithosphere, which
29920-414: The trench. On 19 December Leggo landed at 11°22.11216′N 142°35.250996′E / 11.36853600°N 142.587516600°E / 11.36853600; 142.587516600 at a uncorrected depth of 11,168 metres (36,640 ft) according to its pressure sensor readings. This reading was corrected to 10,929 metres (35,856 ft) depth. Leggo returned with good photography of amphipods feeding on
30107-424: The trench. The first Rainbow Fish lander took photographs, the second took sediment samples, and the third took biological samples. All three landers reached over 10,000 meters, and the third device brought back 103 amphipods. Cui Weicheng, director of Hadal Life Science Research Center at Shanghai Ocean University , led the team of scientists to carry out research at the Challenger Deep in the Mariana Trench. The ship
30294-433: The uncrewed vehicle Kaikō collected mud samples from the seabed . Tiny organisms were found to be living in those samples. In July 2011, a research expedition deployed untethered landers, called drop cams, equipped with digital video cameras and lights to explore this deep-sea region. Among many other living organisms, some gigantic single-celled foraminiferans with a size of more than 10 cm (4 in), belonging to
30481-488: The water from hydrothermal vents, white smokers, and hot spots. Kyoko OKINO from the Ocean Research Institute, University of Tokyo, was principal investigator for this aspect of the cruise. The second goal of the cruise was to deploy a new "10K free fall camera system" called Ashura , to sample sediments and biologics at the bottom of the Challenger Deep. The principal investigator at the Challenger Deep
30668-430: The western basin, and ranging far into the backarc of the Challenger Deep (northward), with significant excursions into the Pacific Plate (southward) and along the trench axis to the east. They hauled eight dredges in the western basin to depths ranging from 10,015 to 10,900 metres (32,858–35,761 ft), and between hauls, cast thirteen free vertical traps. The dredging and traps were for biological investigation of
30855-498: The western basin. On Leg 3 of the Hawaii Institute of Geophysics' (HIG) expedition 76010303, the 156-foot (48 m) research vessel Kana Keoki departed Guam primarily for a seismic investigation of the Challenger Deep area, under chief scientist Donald M. Hussong. The ship was equipped with air guns (for seismic reflection soundings deep into the Earth's mantle ), magnetometer , gravimeter , 3.5 kHz and 12 kHz sonar transducers, and precision depth recorders. They ran
31042-600: The western side of the trench. The Mariana Trench is part of the Izu–Bonin–Mariana subduction system that forms the boundary between two tectonic plates . In this system, the western edge of one plate, the Pacific plate , is subducted (i.e., thrust) beneath the smaller Mariana plate that lies to the west. Crustal material at the western edge of the Pacific plate is some of the oldest oceanic crust on Earth (up to 170 million years old), and is, therefore, cooler and denser; hence its great height difference relative to
31229-493: The world's oceans. Technological advances such as improved multi-beam sonar would be the driving force in uncovering the mysteries of the Challenger Deep into the future. The Scripps research vessel Thomas Washington 's returned to the Challenger Deep in 1986 during the Papatua Expedition, Leg 8 , mounting one of the first commercial multi-beam echosounders capable of reaching into the deepest trenches, i.e.
31416-400: Was 10,920 ± 10 m (35,827 ± 33 ft) at 11°22.4′N 142°35.5′E / 11.3733°N 142.5917°E / 11.3733; 142.5917 ; for the first time documenting the eastern basin as the deepest of the three en echelon pools. In 1993, GEBCO recognized the 10,920 ± 10 m (35,827 ± 33 ft) report as the deepest depth of
31603-537: Was Hiroshi Kitazato of the Institute of Biogeosciences, JAMSTEC. The cruise was titled "Biogeosciences at the Challenger Deep: relict organisms and their relations to biogeochemical cycles". The Japanese teams made five deployments of their 11,000-meter camera system (three to 6,000 meters – two into the central basin of the Challenger Deep) which returned with 15 sediment cores, video records and 140 scavenging amphipod specimens. The Danish Ultra Deep Lander System
31790-513: Was Taishi Tsubouchi of JAMSTEC. The lander Ashura made two descents: on the first, 6 July 2009, Ashura bottomed at 11°22.3130′N 142°25.9412′E / 11.3718833°N 142.4323533°E / 11.3718833; 142.4323533 at 10,867 metres (35,653 ft). The second descent (on 10 July 2009) was to 11°22.1136′N 142°25.8547′E / 11.3685600°N 142.4309117°E / 11.3685600; 142.4309117 at 10,897 metres (35,751 ft). The 270 kg Ashura
31977-509: Was a two-part program: surveying three hydrothermal vent sites in the southern Mariana Trough backarc basin near 12°57'N, 143°37'E about 130 nmi northeast of the central basin of the Challenger Deep, using the autonomous underwater vehicle Urashima . AUV Urashima dives #90–94, were to a maximum depth of 3500 meters, and were successful in surveying all three sites with a Reson SEABAT7125AUV multibeam echosounder for bathymetry, and multiple water testers to detect and map trace elements spewed into
32164-496: Was again put down on the 15th to 10,559 metres (34,642 ft) depth at 11°23.3′N 142°13.8′E / 11.3883°N 142.2300°E / 11.3883; 142.2300 . It was recovered on the 17th with excellent photography of amphipods (shrimp) from the Challenger Deep's western basin. The benthic lander was put down for the third and last time on the 17th, at 11°20.1′N 142°25.2′E / 11.3350°N 142.4200°E / 11.3350; 142.4200 , in
32351-668: Was also used as the support ship of the hybrid remotely operated underwater vehicle (HROV) Nereus that dived three times to the Challenger Deep bottom during the May/June 2009 cruise and did not confirm the sonar established maximum depth by its support ship. Cruise YK09-08 brought the JAMSTEC 4,429-ton research vessel Yokosuka back to the Mariana Trough and to the Challenger Deep June–July 2009. Their mission
32538-577: Was an important gap in information, as the eastern basin was later reported as deeper than the other two basins. Stranger crossed the center basin twice, measuring a maximum depth of 10,830 ± 20 m (35,531 ± 66 ft) in the vicinity of 142°22'E. At the western end of the central basin (approximately 142°18'E), they recorded a depth of 10,805 ± 20 m (35,449 ± 66 ft). The western basin received four transects by Stranger , recording depths of 10,830 ± 20 m (35,531 ± 66 ft) toward
32725-514: Was attained by celestial navigation and LORAN-A . As Gaskell explained, the measurement was not more than 50 miles from the spot where the nineteenth-century Challenger found her deepest depth [...] and it may be thought fitting that a ship with the name Challenger should put the seal on the work of that great pioneering expedition of oceanography. The term "Challenger Deep" came into use after this 1951–52 Challenger circumnavigation, and commemorates both British ships of that name involved with
32912-534: Was employed by Ronnie Glud et al on four casts, two into the central basin of the Challenger Deep and two to 6,000 m some 34 nmi west of the central basin. The deepest depth recorded was on 28 November 2010 – camera cast CS5 – 11°21.9810′N 142°25.8680′E / 11.3663500°N 142.4311333°E / 11.3663500; 142.4311333 }, at a corrected depth of 10,889.6 metres (35,727 ft) (the central basin). With JAMSTEC Cruises YK13-09 and YK13-12, Yokosuka hosted chief scientist Hidetaka Nomaki for
33099-460: Was equipped with a GPS satellite-based radionavigation system. The United States government lifted the GPS selective availability in 2000, so during its 2002 survey, Kairei had access to non-degraded GPS positional services and achieved single-digit meter accuracy in geodetic positioning. The 2.516-ton research vessel Melville , at the time operated by the Scripps Institution of Oceanography, took
33286-583: Was equipped with multiple baited traps, a HTDV video camera, and devices to recover sediment, water, and biological samples (mostly amphipods at the bait, and bacteria and fungus from the sediment and water samples). On 7 October 2010, further sonar mapping of the Challenger Deep area was conducted by the US Center for Coastal & Ocean Mapping /Joint Hydrographic Center (CCOM/JHC) aboard the 4.762-ton Sumner . The results were reported in December 2011 at
33473-449: Was estimated from a conversion of pressure measured and calculations based on the water density from sea surface to seabed. This was followed by the uncrewed ROVs Kaikō in 1996 and Nereus in 2009. The first three expeditions directly measured very similar depths of 10,902 to 10,916 m (35,768 to 35,814 ft; 5,961 to 5,969 fathoms). The fourth was made by Canadian film director James Cameron on 26 March 2012. He reached
33660-538: Was first sounded during the Challenger expedition in 1875 using a weighted rope, which recorded a depth of 4,475 fathoms (8,184 metres; 26,850 feet). In 1877, a map was published called Tiefenkarte des Grossen Ozeans ("Depth map of the Great Ocean") by Petermann, which showed a Challenger Tief ("Challenger deep") at the location of that sounding. In 1899, USS Nero , a converted collier , recorded
33847-555: Was instrumental in gaining an understanding of the subduction of the Pacific Plate under the Philippine Sea Plate . In 1977, Kana Keoki returned to the Challenger Deep area for wider coverage of the forearc and backarc. The Hydrographic Department, Maritime Safety Agency, Japan (JHOD) deployed the newly commissioned 2,600-ton survey vessel Takuyo (HL 02) to the Challenger Deep 17–19 February 1984. Takuyo
34034-472: Was not until February 1996, during Yokosuka 's cruise Y96-06, that Kaikō was ready for its first full depth dives. On this cruise, JAMSTEC established an area of the Challenger Deep (11°10'N to 11°30'N, by 141°50'E to 143°00'E – which later was recognized as containing three separate pools/basins en echelon, each with depths in excess of 10,900 m (35,761 ft)) toward which JAMSTEC expeditions would concentrate their investigations for
34221-404: Was onboard for servicing, Kairei conducted bathymetric surveys and observations. Kairei gridded a survey area about 130 km N–S by 110 km E–W. Kaikō made six dives (#71–75) all to the same location, (11°20.8' N, 142°12.35' E), near the 10,900 metres (35,800 ft) bottom contour line in the western basin. The regional bathymetric map made from the data obtained in 1998 shows that
34408-478: Was recovered on 2–4 November 2015. "Observed sound sources included earthquake signals (T phases), baleen and odontocete cetacean vocalizations, ship propeller sounds, airguns, active sonar and the passing of a Category 4 typhoon." The science team described their results as "the first multiday, broadband record of ambient sound at Challenger Deep, as well as only the fifth direct depth measurement". The 3,536-ton research vessel Xiangyanghong 09 deployed on Leg II of
34595-433: Was sent to 7,646 m depth about 20 nmi due north of the central basin (ABISMO dive #21) specifically to identify possible hydrothermal activity on the north slope of the Challenger Deep, as suggested by findings from Kairei cruise KR08-05 in 2008. AMISMO 's dives #20 and #22 were to 7,900 meters about 15 nmi north of the deepest waters of the central basin. Italian researchers under the leadership of Laura Carugati from
34782-455: Was the crewed descent by Swiss-designed, Italian-built, United States Navy -owned bathyscaphe Trieste , which reached the bottom at 1:06 pm on 23 January 1960, with Don Walsh and Jacques Piccard on board. Iron shot was used for ballast , with gasoline for buoyancy . The onboard systems indicated a depth of 37,800 feet (11,521 m; 6,300 fathoms), but this was later revised to 35,814 feet (10,916 m; 5,969 fathoms). The depth
34969-427: Was the first Japanese ship to be equipped with the new narrowbeam SeaBeam multi-beam sonar echosounder , and was the first survey ship with multi-beam capability to survey the Challenger Deep. The system was so new that JHOD had to develop their own software for drawing bathymetric charts based on the SeaBeam digital data. In just three days, they tracked 500 miles of sounding lines, and covered about 140 km of
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