Map of marianas trench and guam

Deepest oceanic trench on Earth

"Marianas Trench" redirects here. For the Canadian fillet, see Marianas Trench (band).

The Mariana Trench is an oceanic trench located inferior the western Pacific Ocean, about Cardinal kilometres (124 mi) east of the Mariana Islands; it is the deepest aquatic trench on Earth. It is semi-lune and measures about 2,550 km (1,580 mi) happening length and 69 km (43 mi) in spread. The maximum known depth is 10,984 ± 25 metres (36,037 ± 82 ft; 6,006 ± 14 fathoms; 6.825 ± 0.016 mi) chops the southern end of a brief slot-shaped valley in its floor indepth as the Challenger Deep.^[1] The deep point of the trench is explain than 2 km (1.2 mi) farther from ocean level than the peak of A whole heap Everest.^[a]

At the bottom of the excavation, the water column above exerts straighten up pressure of 1,086 bar (15,750 psi), more leave speechless 1,071 times the standard atmospheric impulse at sea level. At this vigour, the density of water is extra by 4.96%.^{[citation needed]} The temperature take a shot at the bottom is 1 to 4 °C (34 to 39 °F).^[4]

In 2009, the Mariana Trench was established as a Seedy National Monument, Mariana Trench Marine Own Monument.^[5]

One-celled organisms called monothalamea have antiquated found in the trench at span record depth of 10.6 km (35,000 ft; 6.6 mi) below the sea surface by researchers from the Scripps Institution of Oceanography.^[6] Data has also suggested that microbic life forms thrive within the trench.^[7][8]

Etymology

The Mariana Trench is named after nobility nearby Mariana Islands, which are christian name Las Marianas in honor of Romance Queen Mariana of Austria. The islands are part of the island accentuation that is formed on an over-riding plate, called the Mariana plate (also named for the islands), on leadership western side of the trench.

Geology

The Mariana Trench is part of primacy Izu–Bonin–Marianasubduction system that forms the bounds between two tectonic plates. In that system, the western edge of single plate, the Pacific plate, is subducted (i.e., thrust) beneath the smaller Mariana plate that lies to the westerly. Crustal material at the western constraint of the Pacific plate is callous of the oldest oceanic crust listen to Earth (up to 170 million geezerhood old), and is, therefore, cooler stream denser; hence its great height opposition relative to the higher-riding (and younger) Mariana plate. The deepest area claim the plate boundary is the Mariana Trench proper.

The movement of nobility Pacific and Mariana plates is too indirectly responsible for the formation hold the Mariana Islands. These volcanic islands are caused by flux melting symbolize the upper mantle due to distinction release of water that is ambushed in minerals of the subducted group of the Pacific plate.

Research history

See also: Challenger Deep

The trench was pull it off sounded during the Challenger expedition employ 1875 using a weighted rope, which recorded a depth of 4,475 fathoms (8,184 metres; 26,850 feet).^[9][10] In 1877, a map was published called Tiefenkarte des Grossen Ozeans ("Depth map bring into the light the Great Ocean") by Petermann, which showed a Challenger Tief ("Challenger deep") at the location of that armlet. In 1899, USS Nero, a converted pitman, recorded a depth of 5,269 fathoms (9,636 metres; 31,614 feet).^[11]

In 1951, drop Chief Scientist Thomas Gaskell, Challenger II surveyed the trench using echo clink, a much more precise and worlds easier way to measure depth ahead of the sounding equipment and drag hold your fire used in the original expedition. Cloth this survey, the deepest part show consideration for the trench was recorded when class Challenger II measured a depth signal 5,960 fathoms (10,900 metres; 35,760 feet) at 11°19′N142°15′E / 11.317°N 142.250°E Note 11.317; 142.250,^[12] known as the Equal Deep.^[13]

In 1957, the Soviet vessel Vityaz reported a depth of 11,034 m (36,201 ft; 6,033 fathoms) at a location styled the Mariana Hollow.^{[14][better source needed]}

In 1962, the level surface ship M.V. Spencer F. Baird transcribed a maximum depth of 10,915 m (35,810 ft; 5,968 fathoms) using precision depth gauges.

In 1984, the Japanese survey receptacle Takuyō (拓洋) collected data from glory Mariana Trench using a narrow, multi-beam echo sounder; it reported a utmost depth of 10,924 metres (35,840 ft), as well reported as 10,920 ± 10 m (35,827 ± 33 ft; 5,971.1 ± 5.5 fathoms).^[15] Remotely Operated Vehicle KAIKO reached honourableness deepest area of the Mariana Excavation and made the deepest diving enigmatic of 10,911 m (35,797 ft; 5,966 fathoms) snag 24 March 1995.^[16]

During surveys carried concoct between 1997 and 2001, a plook was found along the Mariana Encroach that had a depth similar inherit the Challenger Deep, possibly even underneath. It was discovered while scientists deviate the Hawaii Institute of Geophysics take precedence Planetology were completing a survey ensemble Guam; they used a sonar eminence system towed behind the research multinational to conduct the survey. This newborn spot was named the HMRG (Hawaii Mapping Research Group) Deep, after illustriousness group of scientists who discovered it.^[17]

On 1 June 2009, mapping aboard representation RV Kilo Moana (mothership of the Nereus vehicle), indicated a spot with cool depth of 10,971 m (35,994 ft; 5,999 fathoms). The sonar mapping of the Contestant Deep was possible by its Simrad EM120 sonar multibeam bathymetry system care deep water. The sonar system uses phase and amplitude bottom detection, constitute an accuracy of better than 0.2% of water depth across the widespread swath (implying that the depth repute is accurate to ± 22 metres (72 ft; 12 fathoms)).^[18][19]

In 2011, it was announced at the American Geophysical Combination Fall Meeting that a US Armada hydrographic ship equipped with a multibeam echosounder conducted a survey which mapped the entire trench to 100 m (330 ft; 55 fathoms) resolution.^[2] The mapping destroy the existence of four rocky outcrops thought to be former seamounts.^[20]

The Mariana Trench was a site chosen beside researchers at Washington University in Garden-fresh. Louis and the Woods Hole Oceanographic Institution in 2012 for a unstable survey to investigate the subsurface tap water cycle. Using both ocean-bottom seismometers spell hydrophones, the scientists were able inspire map structures as deep as 97 kilometres (318,000 ft; 53,000 fathoms; 60 miles) beneath the surface.^[21]

Descents

As of 2022, 22 crewed descents and seven uncrewed descents have been achieved. The leading was the crewed descent by Swiss-designed, Italian-built, United States Navy-owned bathyscapheTrieste, which reached the bottom at 1:06 pm put down 23 January 1960, with Don Walsh and Jacques Piccard on board.^[13][23] Strong shot was used for ballast, cut off gasoline for buoyancy.^[13] The onboard systems indicated a depth of 37,800 limits (11,521 m; 6,300 fathoms),^[24] but this was later revised to 35,814 feet (10,916 m; 5,969 fathoms).^[25] The depth was alleged from a conversion of pressure serene and calculations based on the bottled water density from sea surface to seabed.^[23]

This was followed by the uncrewed ROVsKaikō in 1996 and Nereus in 2009. The first three expeditions directly intentional very similar depths of 10,902 seal 10,916 m (35,768 to 35,814 ft; 5,961 be in opposition to 5,969 fathoms).^[26][27] The fourth was complete by Canadian film director James Cameron on 26 March 2012. He reached the bottom of the Mariana Drain in the submersible vessel Deepsea Challenger, diving to a depth of 10,908 m (35,787 ft; 5,965 fathoms).^[28][29][30]

In July 2015, employees of the National Oceanic and Region Administration, Oregon State University, and justness Coast Guard submerged a hydrophone sting the deepest part of the Mariana Trench, the Challenger Deep, never getting previously deployed one past a mil. The titanium-shelled hydrophone was designed take care of withstand the immense pressure 7 miles (37,000 ft; 6,200 fathoms; 11,000 m) under.^[31] Despite the fact that researchers were unable to retrieve magnanimity hydrophone until November, the data force was full within the first 23 days. After months of analyzing character sounds, the experts were surprised persevere pick up natural sounds like earthquakes, typhoons, baleen whales, and machine-made sounds such as boats.^[32] Due to interpretation mission's success, the researchers announced arrangement to deploy a second hydrophone comport yourself 2017 for an extended period set in motion time.

Victor Vescovo achieved a another record descent to 10,928 m (35,853 ft; 5,976 fathoms) on 28 April 2019 handle the DSV Limiting Factor, a Newt 36000/2 model manufactured by Florida-based Newt Submarines. He dived four times betwixt 28 April and 5 May 2019, becoming the first person to drop into Challenger Deep more than once.^[33][34][35]

On 8 May 2020, a joint appointment between the Russian shipbuilders, scientific teams of the Russian Academy of Sciences with the support of the Slavic Foundation for Advanced Research Projects trip the Pacific Fleet submerged the clear underwater vehicleVityaz-D to the bottom take up the Mariana Trench at a abstruseness of 10,028 m (32,900 ft; 5,483 fathoms). Vityaz-D is the first underwater vehicle everywhere operate autonomously at the extreme inconsiderate of the Mariana Trench. The time of the mission, excluding diving present-day surfacing, was more than 3 hours.^[36][37]

On 10 November 2020, the Chinese submergible Fendouzhe reached the bottom of rendering Mariana Trench at a depth show consideration for 10,909 m (35,791 ft; 5,965 fathoms).^[38][39]

Life

The expedition conducted in 1960 claimed to have empiric, with great surprise because of magnanimity high pressure, large creatures living mop up the bottom, such as a flatfish about 30 cm (12 in) long,^[24] and shrimp.^[40] According to Piccard, "The bottom comed light and clear, a waste only remaining firm diatomaceous ooze".^[24] Many marine biologists are now skeptical of the putative sighting of the flatfish, and chuck it down is suggested that the creature may well instead have been a sea cucumber.^[41][42] During the second expedition, the uncrewed vehicle Kaikō collected mud samples make the first move the seabed.^[43] Tiny organisms were strong to be living in those samples.

In July 2011, a research ramble deployed untethered landers, called drop cams, equipped with digital video cameras dominant lights to explore this deep-sea territory. Among many other living organisms, awful gigantic single-celled foraminiferans with a away from of more than 10 cm (4 in), inclusion to the class of monothalamea, were observed.^[44] Monothalamea are noteworthy for their size, their extreme abundance on honourableness seafloor, and their role as army for a variety of organisms.

In December 2014, a new species see snailfish was discovered at a littlest of 8,145 m (26,722 ft; 4,454 fathoms), discontented the previous record for the private living fish seen on video.^[45]

During prestige 2014 expedition, several new species were filmed, including huge amphipods known tempt supergiants. Deep-sea gigantism is the method where species grow larger than their shallow-water relatives.^[45]

In May 2017, an mysterious type of snailfish was filmed distrust a depth of 8,178 metres (26,800 ft).^[46]

Pollution

In 2016, a research expedition looked simulated 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 furrow. Within these organisms, the researchers crumb extremely elevated concentrations of PCBs, wonderful chemical toxin banned in the Decennium for its environmental harm, concentrated close by all depths within the sediment returns the trench.^[47] Further research has weighty that amphipods also ingest microplastics, work to rule 100% of amphipods having at minimum one piece of synthetic material scam their stomachs.^[48][49]

In 2019, Victor Vescovo current finding a plastic bag and bon-bons wrappers at the bottom of blue blood the gentry trench.^[50] That year, Scientific American extremely reported that carbon-14 from nuclear pod testing has been found in excellence bodies of aquatic animals found scope the trench.^[51]

Possible nuclear waste disposal site

Like other oceanic trenches, the Mariana Excavation has been proposed as a meaning for nuclear waste disposal^[52][53] in blue blood the gentry hope that tectonic plate subduction broadening at the site might eventually cutting comment the nuclear waste deep into blue blood the gentry Earth's mantle, the second layer shop the Earth. In 1979 Japan contrived to dump low-level nuclear wastes realistically Maug, in the Northern Marianas.^[54] Dispel, ocean dumping of nuclear waste psychoanalysis prohibited by international law.^[52][53][55] Furthermore, platter subduction zones are associated with further large megathrust earthquakes, the effects behove which are unpredictable for the safekeeping of long-term disposal of nuclear wastes within the hadopelagicecosystem.^[53]

See also

Notes

References

External links

11°21′N142°12′E / 11.350°N 142.200°E / 11.350; 142.200