PAGSANJAN ACADEMY SCIENCE 10 THESIS R
THE DEEPEST POINT IN WORLD’S OCEANS
JUSTIN JESS D. PABILONIA
MS. GABRIELE RECTO
In this R.R.L, Im going to tell you the characteristics and the genuinity of this place.
The point of this is to express my opinion about this spectacular body of water.
Mariana Trench is a place where you want to visit but you’ll be a little scared about what will happen to you.
Mariana Trench is an adventurous, a little frightening because of the unusual creatures you’ll see but it will make your mind happy because of fascinating information and facts to feed your mind.
For those who don’t know what is Mariana Trench I will explain it in my main preview of my thesis about this body of water.
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 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 more dense; hence its great height difference relative to 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 release of water that is trapped in minerals of the subducted portion of the Pacific Plate.
The trench 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 (“Deep 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 a depth of 5,269 fathoms (9,636 metres; 31,614 feet).
In 1951, 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, known as the Challenger Deep.
In 1984, the Japanese survey vessel Takuyo collected data from 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 metres (35,830 ft) ±10 m (33 ft). Remotely Operated Vehicle KAIKO reached the deepest area of the Mariana Trench and made the deepest diving record of 10,911 metres (35,797 ft) on March 24, 1995.
Four descents have been achieved. The first was the manned 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 11,521 m (37,799 ft), but this was later revised to 10,916 m (35,814 ft). The depth 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 unmanned ROVs Kaik? 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). The fourth was made by Canadian film director James Cameron in 2012. On 26 March, he reached the bottom of the Mariana Trench in the submersible vessel Deepsea Challenger.
The expedition conducted in 1960 claimed to have observed, with great surprise because of 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, the unmanned vehicle Kaik? 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 dropcams, equipped with digital video and lights to explore this region of the deep sea. Amongst many other living organisms, some gigantic single-celled amoebas with a size of more than 10 cm (4 in), belonging to the class of xenophyophores were observed. Xenophyophores 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), breaking the previous record for the deepest living fish seen on video.
The Mariana Trench or Marianas Trench, located in the western Pacific Ocean approximately 200 kilometres (124 mi) east of the Mariana Islands, and is the deepest known point in the world’s oceans.
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infoplease.com – The Temperature in the Mariana Trench, read 2012-05-13
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Wikipedia- The Mariana Trench, Posted November 16, 2010.
The Deluxe Encyclopedia- Volume IX pp.176-178