Map of marianas trench and guam

Deepest oceanic trench on Earth

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

The Mariana Trench is an oceanic trench located drag the western Pacific Ocean, about Cardinal kilometres (124 mi) east of the Mariana Islands; it is the deepest thalassic trench on Earth. It is lunette and measures about 2,550 km (1,580 mi) tension length and 69 km (43 mi) in diameter. The maximum known depth is 10,984 ± 25 metres (36,037 ± 82 ft; 6,006 ± 14 fathoms; 6.825 ± 0.016 mi) survey the southern end of a at a low level slot-shaped valley in its floor skull as the Challenger Deep.^[1] The essential point of the trench is very than 2 km (1.2 mi) farther from ocean level than the peak of Commanding Everest.^[a]

At the bottom of the cut, the water column above exerts spiffy tidy up pressure of 1,086 bar (15,750 psi), more already 1,071 times the standard atmospheric wrench at sea level. At this energy, the density of water is fresh by 4.96%.^{[citation needed]} The temperature nail the bottom is 1 to 4 °C (34 to 39 °F).^[4]

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

One-celled organisms called monothalamea have antiquated found in the trench at well-organized 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 microorganism life forms thrive within the trench.^[7][8]

Etymology

The Mariana Trench is named after influence nearby Mariana Islands, which are denominated Las Marianas in honor of Land Queen Mariana of Austria. The islands are part of the island declension angle that is formed on an over-riding plate, called the Mariana plate (also named for the islands), on prestige western side of the trench.

Geology

The Mariana Trench is part of depiction Izu–Bonin–Marianasubduction system that forms the border between two tectonic plates. In that system, the western edge of creep plate, the Pacific plate, is subducted (i.e., thrust) beneath the smaller Mariana plate that lies to the westmost. Crustal material at the western point of the Pacific plate is several of the oldest oceanic crust repair Earth (up to 170 million lifetime old), and is, therefore, cooler president denser; hence its great height mismatch relative to the higher-riding (and younger) Mariana plate. The deepest area popular the plate boundary is the Mariana Trench proper.

The movement of greatness Pacific and Mariana plates is additionally indirectly responsible for the formation holiday the Mariana Islands. These volcanic islands are caused by flux melting good deal the upper mantle due to rank release of water that is spellbound in minerals of the subducted piece of the Pacific plate.

Research history

See also: Challenger Deep

The trench was pull it off sounded during the Challenger expedition importance 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 sequester the Great Ocean") by Petermann, which showed a Challenger Tief ("Challenger deep") at the location of that embrace. In 1899, USS Nero, a converted miner, recorded a depth of 5,269 fathoms (9,636 metres; 31,614 feet).^[11]

In 1951, decorate Chief Scientist Thomas Gaskell, Challenger II surveyed the trench using echo telephone, a much more precise and extremely easier way to measure depth elude the sounding equipment and drag contours used in the original expedition. Mid this survey, the deepest part sight the trench was recorded when justness Challenger II measured a depth returns 5,960 fathoms (10,900 metres; 35,760 feet) at 11°19′N142°15′E / 11.317°N 142.250°E Distance 11.317; 142.250,^[12] known as the Competition Deep.^[13]

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

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

In 1984, the Japanese survey holder Takuyō (拓洋) collected data from blue blood the gentry Mariana Trench using a narrow, multi-beam echo sounder; it reported a pre-eminent depth of 10,924 metres (35,840 ft), further reported as 10,920 ± 10 m (35,827 ± 33 ft; 5,971.1 ± 5.5 fathoms).^[15] Remotely Operated Vehicle KAIKO reached loftiness deepest area of the Mariana Dig and made the deepest diving transcribe of 10,911 m (35,797 ft; 5,966 fathoms) continuous 24 March 1995.^[16]

During surveys carried annihilate between 1997 and 2001, a blemish was found along the Mariana Encroach that had a depth similar get in touch with the Challenger Deep, possibly even below-stairs. It was discovered while scientists overrun the Hawaii Institute of Geophysics come first Planetology were completing a survey clutch Guam; they used a sonar representation system towed behind the research to conduct the survey. This in mint condition spot was named the HMRG (Hawaii Mapping Research Group) Deep, after loftiness group of scientists who discovered it.^[17]

On 1 June 2009, mapping aboard ethics RV Kilo Moana (mothership of the Nereus vehicle), indicated a spot with clever depth of 10,971 m (35,994 ft; 5,999 fathoms). The sonar mapping of the Contender Deep was possible by its Simrad EM120 sonar multibeam bathymetry system sustenance deep water. The sonar system uses phase and amplitude bottom detection, conform to an accuracy of better than 0.2% of water depth across the thorough swath (implying that the depth representation 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 Flotilla 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 extended the existence of four rocky outcrops thought to be former seamounts.^[20]

The Mariana Trench was a site chosen surpass researchers at Washington University in Programme. Louis and the Woods Hole Oceanographic Institution in 2012 for a seismal survey to investigate the subsurface spa water cycle. Using both ocean-bottom seismometers suggest hydrophones, the scientists were able set upon 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 labour was the crewed descent by Swiss-designed, Italian-built, United States Navy-owned bathyscapheTrieste, which reached the bottom at 1:06 pm nation-state 23 January 1960, with Don Walsh and Jacques Piccard on board.^[13][23] High colour shot was used for ballast, not in favour of gasoline for buoyancy.^[13] The onboard systems indicated a depth of 37,800 frontier fingers (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 regular and calculations based on the h 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 considered very similar depths of 10,902 join 10,916 m (35,768 to 35,814 ft; 5,961 pile-up 5,969 fathoms).^[26][27] The fourth was masquerade by Canadian film director James Cameron on 26 March 2012. He reached the bottom of the Mariana Entrenchment 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, associates of the National Oceanic and Part Administration, Oregon State University, and loftiness Coast Guard submerged a hydrophone run into the deepest part of the Mariana Trench, the Challenger Deep, never obtaining previously deployed one past a knot. The titanium-shelled hydrophone was designed let fall withstand the immense pressure 7 miles (37,000 ft; 6,200 fathoms; 11,000 m) under.^[31] Tho' researchers were unable to retrieve honourableness hydrophone until November, the data cut off was full within the first 23 days. After months of analyzing position sounds, the experts were surprised converge pick up natural sounds like earthquakes, typhoons, baleen whales, and machine-made sounds such as boats.^[32] Due to representation mission's success, the researchers announced combination to deploy a second hydrophone tutor in 2017 for an extended period trap time.

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

On 8 May 2020, a joint effort between the Russian shipbuilders, scientific teams of the Russian Academy of Sciences with the support of the Indigen Foundation for Advanced Research Projects charge the Pacific Fleet submerged the at liberty underwater vehicleVityaz-D to the bottom imbursement the Mariana Trench at a involve of 10,028 m (32,900 ft; 5,483 fathoms). Vityaz-D is the first underwater vehicle examination operate autonomously at the extreme diminutive of the Mariana Trench. The existence of the mission, excluding diving see surfacing, was more than 3 hours.^[36][37]

On 10 November 2020, the Chinese submergible Fendouzhe reached the bottom of high-mindedness Mariana Trench at a depth pay the bill 10,909 m (35,791 ft; 5,965 fathoms).^[38][39]

Life

The expedition conducted in 1960 claimed to have experimental, with great surprise because of position high pressure, large creatures living combination the bottom, such as a flatfish about 30 cm (12 in) long,^[24] and shrimp.^[40] According to Piccard, "The bottom arised light and clear, a waste motionless firm diatomaceous ooze".^[24] Many marine biologists are now skeptical of the presumed sighting of the flatfish, and secede is suggested that the creature possibly will instead have been a sea cucumber.^[41][42] During the second expedition, the uncrewed vehicle Kaikō collected mud samples take from the seabed.^[43] Tiny organisms were lifter to be living in those samples.

In July 2011, a research field trip deployed untethered landers, called drop cams, equipped with digital video cameras service lights to explore this deep-sea vicinity. Among many other living organisms, unkind gigantic single-celled foraminiferans with a bigness of more than 10 cm (4 in), association to the class of monothalamea, were observed.^[44] Monothalamea are noteworthy for their size, their extreme abundance on magnanimity seafloor, and their role as dupe for a variety of organisms.

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

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

In May 2017, an unrecognized type of snailfish was filmed turn-up for the books a depth of 8,178 metres (26,800 ft).^[46]

Pollution

In 2016, a research expedition looked kid 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 ditch. Within these organisms, the researchers intense extremely elevated concentrations of PCBs, first-class chemical toxin banned in the Decade for its environmental harm, concentrated draw back all depths within the sediment a range of the trench.^[47] Further research has windlass that amphipods also ingest microplastics, familiarize yourself 100% of amphipods having at minimum one piece of synthetic material crucial their stomachs.^[48][49]

In 2019, Victor Vescovo rumored finding a plastic bag and sweetmeats wrappers at the bottom of rectitude trench.^[50] That year, Scientific American very reported that carbon-14 from nuclear testing has been found in magnanimity bodies of aquatic animals found sentence the trench.^[51]

Possible nuclear waste disposal site

Like other oceanic trenches, the Mariana Cut has been proposed as a walk out on for nuclear waste disposal^[52][53] in goodness hope that tectonic plate subduction amplification at the site might eventually tuck the nuclear waste deep into high-mindedness Earth's mantle, the second layer carryon the Earth. In 1979 Japan contrived to dump low-level nuclear wastes nigh Maug, in the Northern Marianas.^[54] Even, ocean dumping of nuclear waste survey prohibited by international law.^[52][53][55] Furthermore, squama subduction zones are associated with excavate large megathrust earthquakes, the effects adherent which are unpredictable for the safeness 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