Exploration of the ocean floor and the deepest dive. Where is the Mariana Trench? What is the Mariana Trench
The Mariana Trench is a fracture in the earth's crust located in the ocean. It is one of the famous objects in the world. Let's find out where the Mariana Trench is located on the map and what it is known for.
What it is?
The Mariana Trench is an oceanic trench, or a break in the earth's crust, located under water. It got its name from the nearby Mariana Islands. In the world this object is known as the most deep place. Depth Mariana Trench in meters – 10994. This is 2000 meters more than the most high mountain planets - Everest.
The British first learned about this depression in 1875 on the Challenger ship. At the same time, the first measurement of its depth was made, which was 8367 meters.
How was the Mariana Trench formed?
It represents the boundary between two lithospheric plates. Here there is a fault in the earth's crust, formed as a result of the movements of these plates. The depression is shaped like a V and its length in kilometers is 1,500.
Location
How to find the Mariana Trench on a world map? It is located in the Pacific Ocean, in its eastern part, between the Philippine and Mariana Islands. The coordinates of the deepest point of the depression are 11 degrees north latitude and 142 degrees east longitude.
Rice. 1. The Mariana Trench is located in the Pacific Ocean
Research
The enormous depth of the Mariana Trench determines the pressure at the bottom, which is 108.6 MPa. This is a thousand times more pressure on the Earth's surface. Naturally, conducting research in such conditions is extremely difficult. However, the secrets and mysteries of the deepest place in the world attract many scientists.
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As already mentioned, the first studies were carried out in 1875. But the equipment of that time did not allow not only to descend to the bottom of the depression, but even to accurately measure its depth. The first dive was carried out in 1960 - then the bathyscaphe “Trieste” sank to a depth of 10915 meters. This study contains many interesting facts, unfortunately, still have no explanation.
The devices recorded sounds reminiscent of the grinding of a saw on metal. With the help of monitors, unclear shadows were visible, with outlines reminiscent of dragons or dinosaurs. The recording was carried out for an hour, then the scientists decided to urgently raise the submersible to the surface. When the device was lifted, many damages were discovered on the metal, which at that time was considered super-strong. The cable was enormously long and 20 cm wide and was half sawn through. Who could have done this is still considered unknown.
Rice. 2. The bathyscaphe Trieste dived into the Mariana Trench
The German Haifish expedition also sank its bathyscaphe into the Mariana Trench. However, they only reached a depth of 7 km and then encountered some difficulties. Attempts to remove the device were unsuccessful. Turning on the infrared cameras, scientists saw a huge lizard holding the bathyscaphe. Whether this was true - today no one can say.
The deepest part of the depression was recorded in 2011 using a special robot diving to the bottom. It reached 10994 meters. This area was called the Challenger Deep.
Is there anyone who went down to the bottom of the Mariana Trench, other than robots and bathyscaphes? Such dives were carried out by several people:
- Don Walsh and Jacques Picard, research scientists, descended on the bathyscaphe Trieste in 1960 to a depth of 10,915 meters;
- James Cameron, an American director, made a solo dive to the very bottom of the Challenger Deep, collecting many samples, photographs and video materials.
In January 2017, he announced his desire to dive into the Mariana Trench famous traveler Fedor Konyukhov.
Who lives at the bottom of the depression
Despite the enormous depth and high pressure of the water column, the Mariana Trench is not uninhabited. Until recently, it was believed that life ceases at a depth of 6000 m and no animals are able to withstand the enormous pressure. In addition, at the level of 2000 m the passage of light stops and below there is only darkness.
Recent research has discovered that even below 6000 m there is life. So, who lives at the bottom of the Mariana Trench:
- worms up to one and a half meters long;
- crustaceans;
- shellfish;
- octopuses;
- sea stars;
- many bacteria.
All these inhabitants have adapted to withstand pressure and darkness, and therefore have specific shapes and colors.
Rice. 3. Mariana Trench Inhabitant
What have we learned?
So, we found out in which ocean the Mariana Trench is located - the deepest place in the world. Its depth significantly exceeds the height itself. big mountains peace. Despite the harsh conditions, the depression is inhabited by a diverse population. Until now, this place is a big mystery, which scientists from all over the world are trying to unravel.
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For the first time, people sank to the bottom of the Mariana Trench (depth - 11.5 km), the deepest oceanic trench known on Earth, using the bathyscaphe Trieste on January 23, 1960. They were US Navy Lieutenant Don Walsh and engineer Jacques Piccard. Since then and until recently, man has not descended to this depth.
Hollywood director James Cameron in a submersibleDeepseaChallenger
52 years later, the director of “Avatar” and “Titanic” James Cameron repeated this path to the deepest point of the ocean, who on March 25 successfully dived to the bottom of the Mariana Trench and returned to the surface. On a special vertical bathyscaphe Deepsea Challenger, two hours after the start of the dive, he reached the bottom at 7:52 am local time. He stayed there for three hours, photographing and collecting samples, after which he successfully returned to the surface.
BathyscapheDeepseaChallenge with James Cameron dives into the depths of the Pacific Ocean
The first people who sank to the bottom of the Mariana Trench stayed there for only 20 minutes, doing a minimal amount of work and seeing almost nothing except the mud and silt that rose from the dive. The past decades have not been in vain. Mr. Cameron's bathyscaphe was properly equipped - this was to be expected from a man who shot one of the most impressive feature films in stereoscopic form and many documentaries about the underwater world.
Deepsea Challenger was equipped with an array of stereoscopic cameras, an LED light tower, a sampling bottle, a robotic arm and a special device capable of capturing small underwater organisms using suction. The deep-sea vehicle itself was created in Australia and has a length of 7 meters and a weight of 11 tons. The compartment in which James Cameron huddled is a sphere with an internal diameter of just over a meter and only allows for a sitting position.
ApparatusDeepseaChallenge sank to the bottom at a speed3-4 knots
The director said in an interview with the BBC before the dive that it was his dream: “I grew up reading science fiction at a time when people lived in a science-fiction reality. People went to the moon, Cousteau studied the ocean. This is the environment in which I grew up, this is what I have appreciated since childhood.”
James Cameron greets ocean explorer Captain immediately after a dive navy USA Don Walsh
James Cameron in the hatchDeepseaChallenge prepares to dive
Another shot of filmmaker and ocean explorer Don Walsh (far right), who was, along with Jacques Piccard, the first man to reach the bottom of the Mariana Trench 52 years ago
James Cameron's Journey in One Minute Animation
In honor of which it, in fact, got its name. The depression is a crescent-shaped ravine on the ocean floor with a length of 2,550 km. with an average width of 69 km. According to the latest measurements (2014), the maximum depth of the Mariana Trench is 10,984 m. This point is located at the southern end of the trench and is called the “Challenger Deep”. Challenger Deep).
The trench was formed at the junction of two lithospheric tectonic plates - the Pacific and Philippine. The Pacific plate is older and heavier. Over the course of millions of years, it “crept” under the younger Philippine Plate.
Opening
The Mariana Trench was first discovered by a scientific expedition of a sailing ship. Challenger" This corvette, which was originally a warship, was converted into a scientific vessel in 1872 specifically for the Royal Society for the Advancement of Natural Sciences of London. The ship was equipped with biochemical laboratories, means for measuring depth, water temperature and soil sampling. That same year, in December, the ship set off for scientific research and spent three and a half years at sea, covering a distance of 70 thousand nautical miles. At the end of the expedition, which was recognized as one of the most scientifically successful since the famous geographical and scientific discoveries of the 16th century, over 4,000 new species of animals were described, in-depth studies of almost 500 underwater objects were carried out, and soil samples were taken from various parts of the world's oceans.
Against the backdrop of the important scientific discoveries made by Challenger, the discovery of an underwater trench especially stood out, the depth of which amazes the imagination of even contemporaries, not to mention scientists of the 19th century. True, initial depth measurements showed that its depth was just over 8,000 m, but even this value was enough to talk about the discovery of the deepest of known to man points on the planet.
The new trench was named the Mariana Trench - in honor of the nearby Mariana Islands, which in turn are named after Marianne of Austria, the Spanish queen, wife of King Philip IV of Spain.
Research into the Mariana Trench continued only in 1951. English hydrographic vessel Challenger II examined the trench using an echo sounder and found that its maximum depth was much greater than previously thought, amounting to 10,899 m. This point was given the name “Challenger Deep” in honor of the first expedition of 1872-1876.
Challenger Abyss
Challenger Abyss is a relatively small flat plain in the south of the Mariana Trench. Its length is 11 km and its width is about 1.6 km. Along its edges there are gentle slopes.
Its exact depth, which is called a meter per meter, is still unknown. This is due to the errors of the echo sounders and sonars themselves, the changing depth of the world's oceans, as well as the uncertainty that the bottom of the abyss itself remains motionless. In 2009, the American vessel RV Kilo Moana determined the depth to be 10,971 m with a probability of error of 22-55 m. Research in 2014 with improved multibeam echo sounders determined the depth to be 10,984. This is exactly what the value is recorded in reference books and is currently considered the closest to the real one.
Dives
Only four scientific vehicles visited the bottom of the Mariana Trench, and only two expeditions included people.
Project "Nekton"
The first descent into the Challenger Abyss took place in 1960 on a manned submersible " Trieste", named after the same name Italian city, where it was created. It was flown by an American US Navy Lieutenant Don Walsh and Swiss oceanographer Jacques Piccard. The device was designed by Jacques' father, Auguste Piccard, who already had experience in creating bathyscaphes.
Trieste made its first dive in 1953 in the Mediterranean Sea, where it reached a record depth of 3,150 m at that time. In total, the bathyscaphe made several dives between 1953 and 1957. and the experience of its operation has shown that it can dive to more serious depths.
Trieste was purchased by the US Navy in 1958 when the United States became interested in seabed exploration in the Pacific region, where some island states came de facto under its jurisdiction as the victorious country in World War II.
After some modifications, in particular further compaction of the outer part of the hull, Trieste began to be prepared for immersion in the Mariana Trench. Jacques Piccard remained the pilot of the bathyscaphe, since he had the most great experience control of Trier in particular and bathyscaphes in general. His companion was Don Walsh, a then-current US Navy lieutenant who served on a submarine and later became a famous scientist and naval specialist.
The project for the first dive to the bottom of the Mariana Trench received a code name Project "Nekton", although this name did not catch on among the people.
The dive began on the morning of January 23, 1960 at 8:23 local time. To a depth of 8 km. the apparatus descended at a speed of 0.9 m/s, and then slowed down to 0.3 m/s. The researchers saw the bottom only at 13:06. Thus, the time of the first dive was almost 5 hours. The submersible stayed at the very bottom for only 20 minutes. During this time, the researchers measured the density and temperature of the water (it was +3.3ºС), measured the radioactive background, and observed an unknown fish similar to a flounder and a shrimp that suddenly appeared at the bottom. Also, based on the measured pressure, the diving depth was calculated, which was 11,521 m, which was later adjusted to 10,916 m.
While at the bottom of the Challenger Abyss we explored and had time to refresh ourselves with chocolate.
After this, the bathyscaphe was freed from ballast and the ascent began, which took less time - 3.5 hours.
Submersible "Kaiko"
Kaiko (Kaikō) - the second of four devices that reached the bottom of the Mariana Trench. But he visited there twice. This uninhabited remote-controlled underwater vehicle was created by the Japan Agency for Marine Science and Technology (JAMSTEC) and was intended to study the deep seabed. The device was equipped with three video cameras, as well as two manipulator arms controlled remotely from the surface.
He made more than 250 dives and made enormous contributions to science, but his most famous journey he committed in 1995, diving to a depth of 10,911 m into the Challenger Deep. It took place on March 24 and samples of benthic extremophile organisms were brought to the surface - this is the name given to animals capable of surviving in the most extreme environmental conditions.
Kayko returned to the Challenger Deep again a year later, in February 1996, and took samples of soil and microorganisms from the bottom of the Mariana Trench.
Unfortunately, Kaiko was lost in 2003 after the cable connecting it to the carrier vessel broke.
Deep-sea submersible "Nereus"
Unmanned remote-controlled deep-sea vehicle " Nereus"(English) Nereus) closes the trio of devices that reached the bottom of the Mariana Trench. His dive took place in May 2009. Nereus reached a depth of 10,902 m. He was sent to the site of the very first expedition to the bottom of the Challenger Abyss. He stayed at the bottom for 10 hours, broadcasting video to the mother ship live from his cameras, after which he collected water and soil samples and successfully returned to the surface.
The device was lost in 2014 during a dive into the Kermadec Trench at a depth of 9,900 m.
Deepsea Challenger
The last dive to the bottom of the Mariana Trench was made by the famous Canadian director James Cameron, inscribing itself not only in the history of cinema, but also in the history of great research. It happened on March 26, 2012 on a single-seat submersible Deepsea Challenger, built under the direction of Australian engineer Ron Alloon in collaboration with National Geographic and Rolex. The main objective of this dive was to collect documentary evidence of life at such extreme depths. From the soil samples taken, 68 new animal species were discovered. The director himself said that the only animal he saw at the bottom was an amphipod - an amphipod, similar to a small shrimp about 3 cm in length. The footage formed the basis documentary film, which tells the story of his dive into the Challenger Deep.
James Cameron became the third person on Earth to visit the bottom of the Mariana Trench. He set a diving speed record - his submersible reached a depth of 11 km. in less than two hours. He also became the first person to reach such a depth in a solo dive. He spent 6 hours at the bottom, which is also a record. Bathyscaphe Trieste was at the bottom for only 20 minutes.
Animal world
The first Trieste expedition reported with great surprise that there was life at the bottom of the Mariana Trench. Although it was previously believed that the existence of life in such conditions was simply not possible. According to Jacques Piccard, they saw at the bottom a fish resembling an ordinary flounder, about 30 cm long, as well as amphipod shrimp. Many marine biologists are skeptical that Trier's crew actually saw the fish, but they do not so much question the researchers' words as they are inclined to believe that they mistook a sea cucumber or other invertebrate for the fish.
During the second expedition, the Kaiko apparatus took soil samples and in fact found many tiny organisms capable of surviving in absolute darkness at temperatures close to 0°C and under monstrous pressure. There is not a single skeptic left who doubts the presence of life everywhere in the ocean, even in the most incredible conditions. However, it remained unclear how developed such deep-sea life was. Or are the only representatives of the Mariana Trench the simplest microorganisms, crustaceans and invertebrates?
In December 2014, a new species of sea slug was discovered - a family of deep-sea marine fish. The cameras recorded them at a depth of 8,145 m, which was an absolute record for fish at that time.
In the same year, cameras recorded several more species of huge crustaceans, differing from their shallow-sea relatives by deep-sea gigantism, which is generally inherent in many deep-sea species.
In May 2017, scientists reported the discovery of another new species of sea slug, which was discovered at a depth of 8,178 m.
All deep sea inhabitants The Mariana Trench are almost blind, slow and unpretentious animals that can survive in the most extreme conditions. Popular stories that the Challenger Deep is inhabited by marine animals, megalodon and other huge animals are nothing more than fables. The Mariana Trench is fraught with many secrets and mysteries, and new species of animals are no less interesting to scientists than relict animals known since the Paleozoic era. Being at such depths for millions of years, evolution has made them completely different from shallow-water species.
Current research and future dives
The Mariana Trench continues to attract the attention of scientists around the world, despite the high cost of research and its weak practical use. Ichthyologists are interested in new species of animals and their adaptive abilities. Geologists are interested in this region from the point of view of the processes occurring in lithospheric plates and the formation of underwater mountain ranges. Ordinary researchers simply dream of visiting the bottom of the deepest trench on our planet.
Several expeditions to the Mariana Trench are currently planned:
1. American company Triton Submarines develops and produces private underwater bathyscaphes. The newest model Triton 36000/3, consisting of a crew of 3 people, is planned to be sent to the Challenger Abyss in the near future. Its characteristics allow it to reach a depth of 11 km. in just 2 hours.
2. Company Virgin Oceanic(Virgin Oceanic), specializing in private shallow dives, is developing a single-person deep-sea vehicle that can deliver a passenger to the bottom of the trench in 2.5 hours.
3. American company DOER Marine working on a project" Deep Search"—one or two-seater submersible.
4. In 2017, famous Russian traveler Fedor Konyukhov announced that he plans to reach the bottom of the Mariana Trench.
1. In 2009 it was created Nautical national monument Mariana Islands. It does not include the islands themselves, but only covers their marine territory, with an area of more than 245 thousand km². Almost the entire Mariana Trench was included in the monument, although its deepest point, the Challenger Deep, was not included in it.
2. At the bottom of the Mariana Trench, the water column exerts a pressure of 1,086 bar. This is a thousand times more than standard atmospheric pressure.
3. Water compresses very poorly and at the bottom of the gutter its density increases by only 5%. This means 100 liters of ordinary water at a depth of 11 km. will occupy a volume of 95 liters.
4. Although the Mariana Trench is considered the deepest point on the planet, it is not the closest point to the center of the Earth. Our planet is not an ideal spherical shape, and its radius is approximately 25 km. less at the poles than at the equator. Therefore, the deepest point on the bottom of the Arctic Ocean is 13 km. closer to the center of the Earth than in the Challenger Deep.
5. The Mariana Trench (and other deep-sea trenches) have been proposed to be used as nuclear waste cemeteries. It is assumed that the movement of plates will “push” waste under the tectonic plate deeper into the Earth. The proposal is not without logic, but the dumping of nuclear waste is prohibited by international law. In addition, zones of junctions of lithospheric plates give rise to earthquakes of enormous force, the consequences of which are unpredictable for buried waste.
There are 5 oceans on Earth, which occupy a significant part of the land. Having conquered space and landed a man on the Moon, sending autonomous spacecraft to the farthest planets solar system, people know negligible little about what is hidden in the depths of the sea on their home planet.
What is the Mariana Trench?
This is the name of the deepest place in the Pacific Ocean known today. It is a trench formed by the convergence of tectonic plates. Maximum depth The Mariana Trench is approximately 10,994 meters (2011 data). There are other trenches in all other oceans, but not so deep. Only the Java Trench (7729 meters) can be compared with the Mariana Trench.
Location
The deepest place on Earth is located in the western Pacific Ocean, near the Mariana Islands. The trench stretches along them for one and a half thousand kilometers. The bottom of the depression is flat, its width ranges from 1 to 5 kilometers. The trench got its name in honor of the islands next to which it is located.
"Challenger Deep"
This is the name given to the deepest place (10,994 meters) of the Mariana Trench. Here it is necessary to explain that it is not yet possible to obtain the exact dimensions of this gigantic trough of the ocean floor. The speed of sound at different depths varies greatly, and the Mariana Trench has a very complex structure, so the data obtained using an echo sounder is always slightly different.
History of discovery
People have long known that deep-sea places exist in the seas and oceans. In 1875, the English corvette Challenger opened one of these points. What depth of the Mariana Trench was recorded then? It was 8367 meters. The measuring instruments at that time were far from ideal, but even this result made a stunning impression - it became clear that the deepest point of the ocean floor on the planet had been found.
Gutter studies
In the 19th century, it was simply impossible to explore the bottom of the Mariana Trench. At that time, there was no technology that would allow one to descend to such a depth. Without modern diving equipment, this was tantamount to suicide.
The trench was re-examined many years later, in the next century. Measurements taken in 1951 showed a depth of 10,863 meters. Then, in 1957, members of the Soviet scientific vessel Vityaz studied the depression. According to their measurements, the depth of the Mariana Trench was 11,023 meters.
The last study of the trench was carried out in 2011.
Cameron's Great Journey
The Canadian director became the third person in the history of Mariana Trench exploration to descend to its bottom. He was the first in the world to do it alone. Before its sinking, the trench was explored by Don Walsh and Jacques Piccard in 1960 using the bathyscaphe Trieste. In addition, Japanese scientists tried to find out the depth of the Mariana Trench using the Kaiko probe. And in 2009, the Nereus apparatus descended to the bottom of the trench.
Descent to such incredible depths comes with a huge number of risks. First of all, a person is threatened by a monstrous pressure of 1100 atmospheres. It can damage the body of the device, which will lead to the death of the pilot. Another serious danger that lurks when descending to depth is the cold that reigns there. It can not only cause equipment failure, but also kill a person. The bathyscaphe may collide with rocks and be damaged.
For many years, James Cameron dreamed of visiting the deepest point of the Mariana Trench - the Challenger Deep. In order to carry out his plans, he equipped his own expedition. Especially for this, an underwater vehicle was developed and built in Sydney - a single-seat bathyscaphe Deepsea Challenger, equipped with scientific equipment, as well as photo and video cameras. In it, Cameron sank to the bottom of the Mariana Trench. This event occurred on March 26, 2012.
In addition to photographs and video footage, the Deepsea Challenger bathyscaphe had to take new measurements of the trench and try to provide accurate data on its dimensions. Everyone was worried about one question: “How much?” The depth of the Mariana Trench, according to the apparatus, was 10,908 meters.
The director was impressed by what he saw below. Most of all, the bottom of the depression reminded him of a lifeless lunar landscape. He did not meet the terrible inhabitants of the abyss. The only creature he saw through the submersible's porthole was a small shrimp.
After a successful voyage, James Cameron decided to donate his bathyscaphe to the Oceanographic Institute so that it could continue to be used to explore the depths of the sea.
Creepy denizens of the deep
The lower the ocean floor, the less sunlight penetrates through the water column. The depth of the Mariana Trench is the reason that impenetrable darkness always reigns in it. But even the absence of light cannot become an obstacle to the emergence of life. Darkness gives birth to creatures that have never seen the sun. And they, in turn, were only recently able to be seen by marine biologists.
This spectacle is not for the faint of heart. Almost all the inhabitants of the Mariana Trench seem to have been born from the imagination of an artist who creates monsters for horror films. Seeing them for the first time, you might think that they do not live next to humans on the same planet, but are alien creatures, they look so alien.
To some extent, this is true - negligible little is known about the oceans and their inhabitants. The bottom of the Mariana Trench has been explored less than the surface of Mars. Therefore, for a long time it was believed that at such a depth life is impossible without sunlight. It turned out that this was not the case. The depth of the Mariana Trench, gigantic pressure and cold are no obstacle to the birth of amazing creatures living in complete darkness.
Most of them have an ugly appearance due to terrible living conditions. The pitch darkness reigning in the depths made the marine inhabitants of these places completely blind. Many fish have huge teeth, such as howliods, which swallow their prey whole.
What can living creatures that are so far from the surface of the ocean eat? At the bottom of the depression, the remains of living organisms accumulate, forming a multi-meter layer of bottom silt. The inhabitants of the depths feed on these deposits. Predatory fish have luminous areas of the body with which they attract small fish.
The gutter is inhabited by bacteria that can only develop at high pressure, single-celled organisms, jellyfish, worms, mollusks, and sea cucumbers. The depth of the Mariana Trench allows them to reach very large sizes. For example, amphipods found at the bottom of the trench are 17 centimeters long.
Amoebas
Xenophyophores (amoebas) are single-celled organisms that can only be seen with a microscope. But at depth, these inhabitants of the Mariana Trench reach gigantic sizes - up to 10 centimeters. Previously, they were found at a depth of 7500 meters. Interesting feature These organisms, in addition to their size, have the ability to accumulate uranium, lead and mercury. Externally, deep-sea amoebas look different. Some are disc or tetrahedron shaped. Xenophyophores feed on bottom sediments.
Hirondellea gigas
Large amphipods (amphipods) have been discovered in the Mariana Trench. These deep-sea crayfish feed on dead organic matter that accumulates at the bottom of the depression and have a keen sense of smell. The largest specimen found was 17 centimeters in length.
Holothurians
Sea cucumbers are another representative of organisms that live at the bottom of the Mariana Trench. This class of invertebrates feeds on plankton and bottom sediments.
Conclusion
The Mariana Trench has not yet been properly explored. No one knows what creatures inhabit it and how many secrets it holds.
The Mariana Trench is not a vertical abyss. This is a crescent-shaped trench stretching for 2.5 thousand km east of the Philippines and west of Guam, USA. The deepest point of the trench, the Challenger Deep, is located 11 km from the surface of the Pacific Ocean. Everest, if it were at the bottom of the depression, would be 2.1 km short of sea level.
Mariana Trench Map
The Mariana Trench (as the trench is also commonly called) is part of a global network of troughs that cross the seabed and were formed as a result of ancient geological events. They arise when two tectonic plates collide, when one layer sinks under the other and goes into the Earth's mantle.
The underwater trench was discovered by the British research ship Challenger during the first global oceanographic expedition. In 1875, scientists tried to measure the depth with a diplot - a rope with a weight tied to it and meter markings. The rope was only enough for 4,475 fathoms (8,367 m). Almost a hundred years later, the Challenger II returned to the Mariana Trench with an echo sounder and established the current depth of 10,994 m.
The bottom of the Mariana Trench is hidden in eternal darkness - the sun's rays do not penetrate to such a depth. Temperatures are just a few degrees above zero - and close to freezing. The pressure in the Challenger Deep is 108.6 MPa, which is approximately 1,072 times the normal atmospheric pressure at ocean level. This is five times the pressure that is created when a bullet hits a bulletproof object and is approximately equal to the pressure inside the reactor for the synthesis of polyethylene. But people found a way to get to the bottom.
Man in the Deep
The first people to visit the Challenger Abyss were American soldiers Jacques Piccard and Don Walsh. In 1960, on the Trieste bathyscaphe, they descended to 10,918 m in five hours. The researchers spent 20 minutes at this mark and saw almost nothing because of the clouds of silt raised by the device. Except for the fish of the flounder species, which was hit by the spotlight. The presence of life under such high pressure was the main discovery of the mission.
Before Piccard and Walsh, scientists believed that fish could not live in the Mariana Trench. The pressure in it is so great that calcium can only exist in liquid form. This means that vertebrate bones must literally dissolve. No bones, no fish. But nature showed scientists that they were wrong: living organisms are capable of adapting even to such unbearable conditions.
Many living organisms in the Challenger Abyss were discovered by the Deepsea Challenger bathyscaphe, on which director James Cameron descended alone to the bottom of the Mariana Trench in 2012. In soil samples taken by the apparatus, scientists found 200 species of invertebrates, and at the bottom of the depression - strange translucent shrimp and crabs.
At a depth of 8 thousand m, the submersible discovered the deepest-sea fish - a new representative of the species of lipariformes or sea slugs. The head of the fish resembles that of a dog, and its body is very thin and elastic - while moving, it resembles a translucent napkin that is carried by the current.
A few hundred meters below live giant ten-centimeter amoebas called xenophyophores. These organisms show amazing resistance to several elements and chemicals such as mercury, uranium and lead that would kill other animals or humans within minutes.
Scientists believe there are many more species in the depths waiting to be discovered. In addition, it is still not clear how such microorganisms - extremophiles - can survive in such extreme conditions.
The answer to this question will lead to breakthroughs in biomedicine and biotechnology and will help understand how life began on Earth. For example, researchers from the University of Hawaii believe that thermal mud volcanoes near the depression may have provided conditions for the survival of the first organisms on the planet.
Volcanoes at the bottom of the Mariana Trench
What kind of rift?
The depression owes its depth to the fault of two tectonic plates - the Pacific layer goes under the Philippine one, forming a deep trench. The regions where such geological events occurred are called subduction zones.
Each plate is almost 100 km thick and the fault is at least 700 km deep from the lowest point of the Challenger Deep. “It's an iceberg. The man wasn't even at the top - 11 are nothing compared to the 700 hiding in the depths. The Mariana Trench is the boundary between the limits of human knowledge and a reality that is inaccessible to humans,” says geophysicist Robert Stern from the University of Texas.
Plates at the bottom of the Mariana Trench Photo: NOAA
Scientists suggest that through the subduction zone into the Earth's mantle there is water in large volumes - rocks at the boundaries of faults act like sponges, absorbing water and transporting it into the bowels of the planet. As a result, the substance ends up at a depth of 20 to 100 km below the seabed.
Geologists from the University of Washington found that over the last million years, more than 79 million tons of water entered the bowels of the earth through the joint - this is 4.3 times more than previous estimates.
The main question is what happens to the water in the depths. It is believed that volcanoes close the water cycle, returning water to the atmosphere in the form of water vapor during eruptions. This theory was supported by previous measurements of the volume of water penetrating the mantle. Volcanoes ejected into the atmosphere approximately equal to the absorbed volume.
A new study disproves this theory - estimates suggest that the Earth absorbs more water than it returns. And this is really strange - given that the level of the World Ocean over the past few hundred years not only has not decreased, but has even increased by several centimeters.
A possible solution is to abandon the theory of equal carrying capacity of all subduction zones on Earth. Conditions in the Mariana Trench are likely more extreme than in other parts of the planet, and more water penetrates into the subsurface through the Challenger Deep rift.
“Does the amount of water depend on the structural features of the subduction zone, for example, on the angle of bending of the plates? We hypothesize that similar faults exist in Alaska and Latin America, but so far man has not been able to discover a deeper structure than the Mariana Trench,” added lead author of the study Doug Vines.
Water hiding in the bowels of the Earth is not the only mystery of the Mariana Trench. The US National Oceanic and Atmospheric Administration (NOAA) calls the region an amusement park for geologists.
This is the only place on the planet where carbon dioxide exists in liquid form. It is ejected from several submarine volcanoes located outside the Okinawa Trough near Taiwan.
At a depth of 414 m in the Mariana Trench is the Daikoku volcano, which is a lake of pure sulfur in liquid form, which constantly boils at a temperature of 187 ° C. 6 km below are geothermal springs that release water at a temperature of 450 °C. But this water does not boil - the process is hampered by the pressure exerted by the 6.5-kilometer water column.
The ocean floor is currently less studied by humans than the Moon. Scientists will probably be able to discover faults deeper than the Mariana Trench, or at least study its structure and features.
