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The Mariana trench lies in the west of the Pacific Ocean, south of Japan. Its depth varies along its 1580-mile length but the deepest point confirmed so far , known as Challenger Deep, reaches a depth of 10,984 metres (36,037 feet).

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Adaptations in Marine Organisms: The Deep Sea

Where light no longer reaches the depth of the ocean, pressure is 10 times stronger than it is on land, and with only a small amount of oxygen and food, many organisms manage to survive and even thrive. Without any light from the sun, primary producers, such as phytoplankton (phytoplankton process light to create energy in the form of "food") are no longer able to survive and therefore, there is a limited supply of oxygen in zones 200 meters below the surface of the ocean. The temperature of the ocean is also affected by light. Further below the ocean no light can penetrate, making the deep ocean significantly cooler. Pressure builds up the deeper a creature travels due to the weight of the water above pushing down on any organism. Food is scarce, making it crucial for organisms to conserve energy. This is done by slowing down metabolic activity and reducing movement. To survive the deep dark oceans, organisms have made physical adaptations to: pressure, light temperature, and lack of food; these adaptations lead to odd physical characteristics, giving organisms a reputation for such peculiar appearances.

Thousands of meters below the ocean, pressure builds up, amounting to 500 times more pressure than on land. Marine organisms deal with pressure in a variety of ways. Most deep sea fishes have adapted significantly from surface level fishes internally. Surface level, or epipelagic fish, have a mechanism called a gas bladder used to maintain buoyancy. The bladder can be filled with gas to rise to the surface of the ocean, or compressed to sink down. However, deep sea fish are unable to do this because the amount of pressure would burst the gas bladder and lead to death (2). To withstand such high pressures all marine organisms living in the deep sea are compressed: significantly less bones, and "watery"/more flexible like muscles, which can withstand pressure better than any land organism. Although these adaptations give marine organisms odd appearances, what makes them look incredibly odd is the change in pressure when they are taken out of their habitat. The change in pressure often causes eyes to bulge and enlargement of body parts, like Blobfish (2). But, not all deep sea marine organisms live thousands of meters below the surface. Some only hunt there for extended periods of time like the Sperm Whale. The sperm whale lacks many evolutionary adaptations to withstand pressure, so they make temporary changes like releasing almost 90% of the oxygen into their bloodstream, which allows their lungs to compress (1).

Another challenge deep sea marine organisms have overcome is the lack of light and freezing temperatures. Because light only penetrates 200 meters below the surface it is pitch black in the depths. To see, some organisms produce light through bioluminescence; a chemical reaction that causes light to be emitted in a green or blue wavelength. Marine creatures tend to use this light in two ways: seeing surroundings and navigating their way through the pitch black. Or, for hunting. Light is attractive to many organisms living in the dark, so the light acts as a lure for prey, and when close enough the predator kills the unsuspecting organism (3). Lantern fish are a popular example of this hunting technique, using their long antena with a "light bulb" hanging off. Because no light penetrates the deep ocean, freezing temperatures also pose an issue to deep sea animals. One solution is turning off or slowing down metabolisms, and instead using that energy as heat. Some organisms are cold blooded which means they are unable and do not need to regulate body temperature, easily allowing them to deal with freezing conditions (4).

Perhaps the most difficult obstacle deep ocean organisms face is lack of food. Because the deep ocean has less organisms than the surface level, scarcity of food is common. The primary food input for many in the deep ocean is called detritus, an organic waste of creatures above. Detritus falls down from higher areas of the ocean, and looks similar to snow falling. Using muscles to move requires energy, which means that the less movement the more efficient an organism is with their energy. Many marine organisms have accomplished minute amounts of movement. Most living creatures in the deep sea are known as drifters - allowing the current of the ocean to carry them in a singular direction - this conserves a significant amount of energy, while still moving to different locations to search for food. The larger organisms that are not drifters have long flexible jaws that allow them to engulf any possible food nearby (6).

Organisms in the deep sea have come to make some of the oddest and peculiar adaptations to survive in their environments under extreme conditions. As the world and its climate constantly changes, organisms will continue to conform their bodies and behavior to fit the climatic differences.
Works Cited
Fanny de Busserolles, and Justin Marshall. "Seeing in the Deep-Sea: Visual Adaptations in Lanternfishes." The Royal Society Publishing, Royal Society Publishing, 5 Apr. 2017, royalsocietypublishing.org/doi/full/10.1098/rstb.2016.0070. Accessed 9 Oct. 2022. (1)

Monterey Bay Aquarium. "Illuminating the Facts of Deep-Sea Bioluminescence." Monterey Bay Aquarium, 15 Nov. 2021, www.montereybayaquarium.org/stories/bioluminescence#:~:text=Bioluminescence%20is%20most%20commonly%20blue-green%2C%20probably%20because%20the,all%20the%20red%20light%20has%20been%20filtered%20out. Accessed 9 Oct. 2022. (2)

Omondi, Sharon. "How Do Deep Sea Creatures Survive the High-Water Pressure?" World Atlas, 10 Sept. 2019, www.worldatlas.com/articles/how-do-deep-sea-creatures-survive-the-high-water-pressure.html. Accessed 9 Oct. 2022. (3)

Priyadarshi, Sonali. "Deep Sea Adaptations." Biology Discussion, 6 Mar. 2017, www.biologydiscussion.com/biology/deep-sea-adaptations/4601. Accessed 9 Oct. 2022. (4)

Wurzbacher, Jessica. "Life in the Deep-Sea." Ocean Crusader, 27 Mar. 2012, oceancrusaders.org/life-in-the-deep-sea/#:~:text=The%20deep%20sea%20is%20an%20extremely%20harsh%20environment.,%2837-50oF%2F3-10oC%29%20and%20consequently%20has%20low%20levels%20of%20oxygen. Accessed 9 Oct. 2022. (5)

Zhong, Haoui. "Novel Insights into the Thaumarchaeota in the Deepest Oceans: Their Metabolism and Potential Adaptation Mechanisms." Microbiome, BMC, 1 June 2020, microbiomejournal.biomedcentral.com/articles/10.1186/s40168-020-00849-2. Accessed 9 Oct. 2022. (6)

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Adaptations in Marine Organisms: The Deep Sea

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Independent research conducted by Nathan Pearce '23, advised by Sarah Schulwitz.

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Imagine the deepest, darkest place on Earth-an underwater trench plummeting to a depth of 35,800 feet, nearly seven miles below the ocean surface. The Mariana Trench is one of the least explored places on Earth. Deep enough to swallow Mt. Everest, the Mariana Trench was first pinpointed in 1951 by the British Survey ship Challenger II.

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The conditions in the deep ocean are vastly different - and arguably more extreme - than those found in more shallow ocean waters, making these habitats different from other places on Earth.

As you travel from the surface of the ocean downward to the seafloor, water pressure increases by one atmosphere (or 14 pounds per square inch) for every 10 meters (32.8 feet) of depth. This means, for example, at 100 meters (328 feet), you would experience one atmosphere of air pressure and 10 atmospheres of water pressure, for a total of 11 atmospheres. Travel to 1,000 meters (3,280 feet) below the ocean's surface and most organisms with gas-filled spaces (e.g., lungs) would be crushed by the pressures that other deep-sea life experience.

Light is virtually absent in the deep ocean, which means that deep-sea organisms cannot rely on vision for feeding, avoiding being eaten, or mating. Without sunlight, photosynthesis, the process by which plants make food, is not possible; this contributes to a general scarcity of food in the deep ocean and thus a lower overall density of organisms in many parts of the deep ocean. Chemosynthetic communities in the vicinity of hydrothermal vents and cold seeps are an exception, since they are not dependent upon photosynthesis as a primary food source.

The lack of light in the deep ocean also means that it is very cold down there; below about 200 meters (656 feet) depth, ocean waters have an average temperature of only 4°C (39°F).

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What conditions exist for life in the deep ocean?

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The conditions in the deep ocean are vastly different - and arguably more extreme - than those found in more shallow ocean waters, making these habitats different from other places on Earth. As you travel from the surface of the ocean downward to the seafloor, water pressure increases by one atmosphere (or 14 pounds per square inch) for every 10 meters (32.8 feet) of depth.

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Welcome to the mysterious depths of the Mariana Trench, the world's deepest ocean trench, where fascinating secrets lie hidden beneath the Pacific Ocean's surface. At about 11,000 meters deep, the Mariana Trench is the deepest known point on Earth. Located in the western Pacific Ocean, this astonishing natural wonder was formed by the collision of two tectonic plates. The bone-crushing pressure and freezing temperatures create a harsh environment that challenges life.

Despite the harsh conditions, scientists have made amazing discoveries in the Mariana Trench. Over 200 microorganisms and small creatures live here, adapting to the dark and high pressure. These unique organisms have traits like cartilage bodies instead of bones and the ability to produce light through bioluminescence.

However, the Mariana Trench is not untouched by human activity. Pollution and microplastics have been found in its depths, reminding us of the impact our actions have on even the most remote parts of our planet. Research and exploration of the trench continue, with potential for important discoveries about life and our changing environment. Scientists from different countries work together to understand and preserve this deep-sea wonder for future generations.

Unveiling the Depths: Exploring the Mariana Trench

Explore the deep-sea world as we reveal the secrets of the Mariana Trench. Located in the western Pacific Ocean, this enigmatic trench holds the title of being the deepest known point on Earth, reaching an astonishing depth of about 11,000 meters. With its extreme conditions and unknown wonders, the Mariana Trench has captivated the curiosity of scientists and researchers, spurring a quest for knowledge unlike any other.

Exploring the Mariana Trench has been marked by new technology and strong determination. Scientists use deep-sea submersibles and ROVs to explore and study the depths. These tools help researchers capture stunning images and collect valuable data, giving a glimpse into a rarely visited environment.

As exploration continues, scientists face many challenges. The immense pressure and freezing temperatures pose significant obstacles, making it a harsh and inhospitable environment for life to thrive. Despite these harsh conditions, researchers have found many microorganisms and small creatures adapted to the dark and high pressure. Some of these remarkable adaptations include cartilaginous bodies and the ability to produce their own light through bioluminescence, offering a glimpse into the incredible resilience of life in the deep sea.

With each expedition, we come closer to unraveling the mysteries hidden within the Mariana Trench. Exploring this unique ecosystem helps us understand the diverse life forms living there. It also shows us the impact of human activity. Pollution and microplastics have found their way into the trench, highlighting the urgent need for conservation efforts to protect this unique and fragile ecosystem. By delving into the depths of the Mariana Trench, we have the opportunity to gain valuable insights into our changing environment and the importance of preserving the wonders that lie beneath the surface of our planet.

Location

Western Pacific Ocean

Depth

Approximately 11,000 meters

Extreme Conditions

Bone-crushing pressure and freezing temperatures

Life Forms

Over 200 microorganisms and small creatures

Adaptations

Cartilaginous bodies, bioluminescence

Human Impact

Pollution, microplastics

Significance

Insights into life and the changing environment

Descent into Darkness: The Intense Pressure and Temperature

Brace yourself for the intense journey into the abyss as we explore the extraordinary pressure and freezing temperatures that define the enigmatic Mariana Trench. Located in the western Pacific Ocean, this trench reaches a depth of about 11,000 meters, making it the deepest known point on Earth.

The extreme conditions found in the Mariana Trench present a challenging environment for any form of life. The pressure at these depths is crushing, exerting over 1,000 times the pressure experienced at sea level. To put it into perspective, imagine the weight of more than 50 jumbo jets resting on an area the size of a postage stamp. Additionally, temperatures in the trench drop to freezing levels due to the absence of sunlight.

Despite these inhospitable conditions, researchers have made remarkable discoveries in the Mariana Trench. Over 200 microorganisms and small creatures have been found thriving in this dark and high-pressure environment. To adapt to their surroundings, these organisms have developed extraordinary survival strategies. Some have bodies made of cartilage instead of bones, allowing them to withstand the immense pressure. Others have evolved the ability to produce their own light through a process called bioluminescence, illuminating the darkness with their natural glow.

However, the Mariana Trench is not immune to the impact of human activity. Recent studies have revealed the presence of pollution and microplastics in its depths, highlighting the need for conservation efforts to protect this unique ecosystem. Ongoing research and exploration of the Mariana Trench could unlock further insights into life's ability to endure extreme conditions and provide valuable knowledge about our changing environment.

Extreme Conditions

Microorganisms and Small Creatures

Bone-crushing pressure

Cartilaginous bodies

Freezing temperatures

Bioluminescence

Adapting to the darkness and high pressure

Bizarre Adaptations: Life in the Depths

Prepare to be captivated by the extraordinary adaptations of the resilient inhabitants that call the Mariana Trench their home, defying the odds of survival in this harsh and mysterious realm. In this dark and extreme environment, more than 200 microorganisms and tiny creatures have been discovered, each displaying unique and fascinating adaptations to thrive in the depths.

These extraordinary organisms have adapted to the bone-crushing pressure and freezing temperatures of the trench, where the pressure can be over 1,000 times greater than at sea level and temperatures hover just above freezing. To survive, some of these creatures have evolved bodies made of cartilage instead of bones, allowing them to withstand the immense pressure without collapsing. Others have developed the ability to produce their own light through bioluminescence, illuminating the depths and creating a mesmerizing spectacle.

Moreover, the microorganisms found in the Mariana Trench have revealed surprising adaptations. Some have developed the ability to consume and break down organic compounds, surviving in an environment that lacks sunlight and traditional sources of energy. Others have unique genetic characteristics that allow them to withstand the extreme conditions of the trench. These adaptations not only provide insights into the limits of life on Earth but also offer potential applications in fields such as medicine, biotechnology, and environmental conservation.

The Remarkable Biodiversity of the Mariana Trench

Exploring the Mariana Trench has unveiled a world of biodiversity and biological diversity that was previously unknown. It is a testament to the resilience and adaptability of life, even in the most inhospitable and extreme environments. The discoveries made in the trench have challenged our understanding of what is possible and expanded our knowledge of the diversity of life on Earth.

Snailfish

Flexible bodies and large mouths for consuming prey in the darkness.

Giant Amphipod

Enlarged size and thin exoskeleton to resist the immense pressure.

Mariana Trench Microbes

Ability to utilize alternative energy sources, such as sulfur compounds, in the absence of sunlight.

Undoubtedly, there is still much to discover about the extraordinary adaptations and secrets that lie within the Mariana Trench. With ongoing research and exploration, we are continuously unlocking the mysteries of this deep-sea wonder and gaining valuable insights into the limits of life on our planet. It is a testament to the resilience of nature and a reminder of the awe-inspiring diversity that exists beneath the Earth's surface.

A Window into Earth's Changing Environment

Shed light on the alarming effects of human activity as we explore the pollution and presence of microplastics that threaten the delicate balance of the Mariana Trench. This deepest ocean trench, located in the western Pacific Ocean, is not immune to the reach of human impact. As we delve into its depths, scientists have discovered that the Mariana Trench is not only home to awe-inspiring organisms but also a concerning buildup of pollution.

Sadly, the effects of human activity are far-reaching, even in the most remote and inaccessible areas of our planet. Microplastics, tiny fragments of plastic, have made their way into the Mariana Trench, posing a threat to the unique ecosystem that thrives in its depths. These microplastics, often from sources like ocean pollution and discarded waste, can enter the food chain, endangering the delicate balance of life in the trench.

It is crucial that we address the issue of pollution in the Mariana Trench and take steps to protect this incredible natural wonder. Efforts are underway to raise awareness about the impact of human activity on this remote environment and to implement sustainable practices that minimize pollution. By reducing our plastic consumption, properly disposing of waste, and supporting initiatives to clean up our oceans, we can help preserve the beauty and biodiversity of the Mariana Trench for future generations to explore and appreciate.

Impact of Human Activity on the Mariana Trench

Microplastics: Present in the trench, threatening the ecosystem

Pollution: Human-induced pollution reaching even the deepest parts of the ocean

Delicate Balance: Disruption of the fragile equilibrium in the trench's ecosystem

Preservation Efforts: Awareness and initiatives to protect the Mariana Trench

The Quest for Knowledge: The Significance of Research

Embark on a quest for knowledge as we unravel the importance of ongoing research and exploration of the Mariana Trench, with the potential to unearth groundbreaking discoveries about life and our evolving planet. The Mariana Trench, situated in the western Pacific Ocean, is a mysterious abyss that holds the title of being the deepest known point on Earth, plunging to a staggering depth of approximately 11,000 meters.

These extreme conditions present a unique opportunity for scientific exploration, allowing us to delve into the depths of the unknown. Despite the bone-crushing pressure and freezing temperatures, researchers have already made remarkable discoveries in the trench. More than 200 microorganisms and small creatures have been found to thrive in this inhospitable environment, showcasing their incredible adaptations to survive the darkness and high pressure.

These extraordinary findings not only shed light on the resilience of life but also provide valuable insights into the impact of extreme environments on our planet. The Mariana Trench acts as a window into Earth's changing environment, offering clues about the effects of human activity. Unfortunately, pollution and microplastics have been detected in the depths of the trench, highlighting the urgent need for conservation efforts to protect this fragile ecosystem.

By continuing to study and explore the Mariana Trench, we can gain a deeper understanding of our planet's biodiversity, the adaptations of life in extreme conditions, and the consequences of human actions. The significance of this research extends far beyond the depths of the trench, providing valuable knowledge that can help us preserve and sustain our planet for future generations. Together, let us embark on this quest for knowledge and unlock the secrets hidden in the depths of the Mariana Trench.

- The Mariana Trench is the deepest known point on Earth, with a depth of approximately 11,000 meters.

- Ongoing research and exploration of the trench have revealed over 200 microorganisms and small creatures adapted to survive in extreme conditions.

- The Mariana Trench provides valuable insights into the impact of human activity on the environment, with evidence of pollution and microplastics in its depths.

- Continued research in the Mariana Trench can lead to groundbreaking discoveries about life and our changing planet.

Conservation Efforts: Protecting the Mariana Trench

Learn about the dedicated conservation efforts and crucial steps taken to safeguard the Mariana Trench, ensuring the preservation of its awe-inspiring wonders for generations to come.

The Mariana Trench, with its unique ecosystem and fragile balance, requires diligent conservation efforts to protect its delicate environment. International organizations, governments, and scientific communities have recognized the importance of preserving this deep-sea wonder and have taken significant steps to ensure its longevity.

Efforts to conserve the Mariana Trench focus on reducing pollution and preventing further degradation of its pristine waters. Strict regulations have been implemented to control waste disposal and limit industrial activities in the surrounding areas. These measures aim to minimize the impact of human activity and preserve the integrity of this natural wonder.

Conservation Efforts:

Achievements:

Regulation and Monitoring

Implementation of strict regulations to control waste disposal and industrial activities in the vicinity of the trench. Regular monitoring to ensure compliance with environmental standards.

Research and Education

Continued research to understand the unique ecosystem of the trench. Education programs to raise awareness about the importance of conservation and the need to protect this fragile habitat.

International Cooperation

Collaborative efforts between nations to share data, resources, and expertise for the benefit of the Mariana Trench. Joint campaigns to spread awareness and promote sustainable practices.

Habitat Preservation

Designation of protected areas within the trench to preserve critical habitats. The establishment of marine reserves to safeguard the diverse range of species that call the Mariana Trench home.

Preservation for Future Generations

The conservation of the Mariana Trench is crucial not only for the preservation of its awe-inspiring wonders but also for the understanding of Earth's changing environment. By safeguarding this unique ecosystem, we can gather valuable insights into the adaptability of life under extreme conditions and the potential impacts of human activity.

However, the responsibility to protect the Mariana Trench does not lie solely with governments and organizations. Each individual can contribute to conservation efforts by adopting sustainable practices and spreading awareness. By understanding the importance of this deep-sea wonder, we can inspire future generations to appreciate and protect the hidden marvels of our planet.

Together, through international collaboration, research, education, and sustainable practices, we can ensure that the Mariana Trench continues to captivate us with its mysteries and remains a beacon of hope for the preservation of Earth's natural wonders.

Scientific Collaboration: International Exploration

Discover the remarkable scientific collaborations and international partnerships that drive the exploration and understanding of the Mariana Trench, transcending boundaries in the pursuit of knowledge. Scientists from around the world have come together to unravel the mysteries hidden in the deepest reaches of the ocean. Through shared resources, expertise, and technological advancements, these collaborations have revolutionized our understanding of this enigmatic undersea realm.

International partnerships in deep-sea exploration have enabled researchers to deploy state-of-the-art submersibles and remotely operated vehicles (ROVs) to navigate the treacherous depths of the Mariana Trench. By pooling their resources, these teams have achieved breakthroughs in capturing high-resolution images, collecting samples, and conducting scientific experiments in this extreme environment. The collaboration between scientists, technicians, and engineers from different nations has fostered a wealth of knowledge about the unique geological, biological, and chemical processes at play in the trench.

Scientists, technicians, and engineers from different countries have learned a lot about the unique processes in the trench. These partnerships not only facilitate the sharing of data and findings but also foster a rich exchange of ideas and perspectives. By combining their collective expertise, researchers are able to tackle complex scientific questions and develop innovative research methodologies that push the boundaries of exploration in the Mariana Trench. The power of collaboration lies in its ability to bring together diverse skills, perspectives, and resources, ultimately leading to a deeper understanding of this mysterious and fragile ecosystem.

As our understanding of the Mariana Trench continues to evolve, so too does the need for sustained collaboration and international cooperation. By working together, scientists can expand our knowledge of this unique environment and its implications for the broader ecosystem and global climate. Through these scientific partnerships, we can unlock the secrets of the deep sea and preserve this natural wonder for future generations.

Benefits of International Collaboration in Mariana Trench Exploration

- Shared resources and expertise

- Technological advancements and access to cutting-edge equipment

- Exchange of ideas and perspectives

- Development of innovative research methodologies

- Deeper understanding of the Mariana Trench ecosystem

- Implications for broader ecosystem and global climate

- Preservation of the Mariana Trench for future generations

Discovering the Unknown: Future Expeditions

Embark on a journey into the uncharted as we unveil the excitement and anticipation surrounding upcoming expeditions and research initiatives set to further unravel the mysteries of the Mariana Trench. As scientific curiosity drives us deeper into the ocean depths, new expeditions are being planned to delve into the unexplored regions of this remarkable underwater world.

Leading the charge is an international collaboration of researchers and scientists, pooling their expertise and resources to push the boundaries of deep-sea exploration. With advancements in technology and submersible vehicles, these upcoming expeditions aim to reach even greater depths, where no human has ventured before.

Equipped with state-of-the-art deep-sea submersibles and remotely operated vehicles (ROVs), these scientific missions will capture high-resolution footage, collect samples, and gather valuable data about this mysterious ecosystem. The goal is to understand how the trench's organisms adapt and how human activity affects this fragile environment.

Future Discoveries and Collaborations

The upcoming expeditions in the Mariana Trench hold the promise of revealing new and fascinating discoveries. Scientists anticipate uncovering novel species, further deciphering the intricate food webs, and gaining insights into the impact of climate change on this extreme habitat.

Benefits of Future Expeditions

Collaborating Partners

Increased understanding of deep-sea ecosystems

Insights into the unique adaptations of organisms

Discovery of new species

Assessment of the impact of climate change on the trench

International scientists from various countries

Research institutions and universities

Marine conservation organizations

Government agencies

These future expeditions would not be possible without the collaboration and support of diverse stakeholders, including international scientists, research institutions, marine conservation organizations, and government agencies. It is through these partnerships that the pursuit of knowledge and preservation of the Mariana Trench can be achieved.

As we eagerly await the findings that lie ahead, let us recognize the significance of these upcoming expeditions and the potential they hold for unlocking the secrets of the deep. The Mariana Trench, with its unfathomable depths and hidden wonders, continues to captivate our imagination and inspire a sense of awe for our planet's vast and diverse marine ecosystems.

The Mariana Trench: A Deep-Sea Wonder

Reflect on the unparalleled wonders of the Mariana Trench as we conclude our exploration of the world's deepest ocean trench, a testament to the remarkable diversity and resilience of life on Earth's oceanic frontier.

Nestled in the western Pacific Ocean, the Mariana Trench is an awe-inspiring natural marvel. Its formation, resulting from the collision of tectonic plates, has created a place of immeasurable depth, reaching down approximately 11,000 meters-deeper than any other known point on our planet. The extreme conditions found within the trench, characterized by bone-crushing pressure and freezing temperatures, make it an inhospitable environment for most forms of life.

Yet, against all odds, scientists have made astonishing discoveries in the Mariana Trench. Over 200 microorganisms and small creatures have been found thriving in this seemingly inhospitable realm. These remarkable organisms have adapted and evolved to survive the intense pressure and darkness. Some possess bodies made of cartilage, allowing them to withstand the crushing weight of the deep-sea environment. Others harness the power of bioluminescence, creating their own light in the pitch-black depths.

While the Mariana Trench is a testament to the wonders of our planet, it is also a stark reminder of the impact of human activity on our oceans. Pollution and microplastics have been found even in these remote depths, posing a threat to the delicate balance of this unique ecosystem. The importance of preserving this natural wonder for future generations cannot be overstated.

As we conclude our journey through the mysteries of the Mariana Trench, it is vital to recognize the significance of ongoing research and exploration. By delving deeper into this realm, we have the opportunity to unlock vital knowledge about life's adaptability and the changing environment on Earth. The Mariana Trench is a symbol of our never-ending quest for discovery and our responsibility to protect the wonders within our reach.

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The World's Deepest Ocean Trench: The Mariana Mystery

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Discover the intriguing Mariana Trench Depth, as you delve into the darkest mysteries of the world's deepest ocean trench. Dive in now!

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It's a glorious sunny morning out at sea-I have to wear sunglasses up on deck from the glare off the water, and plenty of sunblock on my nose! In about five hours, the ALVIN will return from a day at the vents, and I can't wait to hear about the latest data the researchers have collected.

The researchers in ALVIN certainly don't need to wear sunglasses. It's dark down there at the bottom of the sea-darker than you can probably even imagine! Let me explain...

The ocean is very, very deep; light can only penetrate so far below the surface of the ocean. As the light energy travels through the water, the molecules in the water scatter and absorb it. At great depths, light is so scattered that there is nothing left to detect. Only the very top layers of the ocean get enough light to support plants, and most of the truly abundant animal life is crowded into the top 200 meters. This upper region is called the photic zone; almost all of the marine plants and tiny microscopic marine organisms that engage in photosynthesis can thrive only in the photic zone.

Two hundred meters is a lot of ocean, right? Maybe, but the depth of the photic zone is only a tiny fraction of the ocean's total depth. (The depth of the ocean varies greatly depending on where you are; here at the Juan de Fuca Ridge, the depth below me is about 2,300 meters (~1.5 miles). The greatest ocean depth ever measured, at the Mariana Trench in the Western Pacific, is about 11,000 meters, almost seven miles!) Below the photic zone, from 200 to 1,000 meters, is the aphotic (a meaning without and photic meaning light) zone. In the aphotic zone; all that's left of sunlight is a dim, dark, blue-green light, too weak to allow photosynthesis to occur. There is food to be had, though; detritus, bits of decaying plants, and animal waste falls from above to feed the organisms in the aphotic zone.

After the aphotic zone, there's complete darkness. From 1,000 meters below the surface, all the way to the sea floor, no sunlight penetrates the darkness; and because photosynthesis can't take place, there are no plants, either. Animals that live in the abyssal zone feed on detritus raining down from above-or on each other. And sometimes they make their own light; certain species of deep sea fish and jellyfish have special light-producing cells.

Obviously, organisms who live at the deep sea vents can't rely on the Sun; instead, many of them rely on the chemicals that come out of the vents-the process they use to create food is called chemosynthesis instead of photosynthesis. Pretty amazing, right? But how can we even see them from the ALVIN if it's so dark down there?

As the ALVIN reaches the bottom of the ocean, there is no natural light. The pilots plot the position of the sub with both standard navigation equipment and with special topographical (or 3-D) maps that are made by side scan sonar. To find a specific site, the pilots use the 3-D maps, but they must also rely on visual clues. Visual work is difficult because they only have the light of the sub. Imagine looking for rock samples on land in total darkness, with only a flashlight-things seem to suddenly loom out of the blackness, and it's hard to see enough to find what you're looking for. These folks are often trying to find a single small probe, only a couple meters in length, or a specific spot they've visited before. Talk about a needle in a haystack! So it's quite helpful to have a pilot who knows the area well; it's a bit like when you hike-you look at the map, but even the best map doesn't show the individual trees that you recognize as you become familiar with a specific place.

To see what's around the sub, the ALVIN pilots use the spotlights on the outside of the sub and the video cameras mounted on the front of the sub to see what's around it. There is also a small porthole for a direct view of the outside. The lights of the sub penetrate about 30 feet into the darkness. Video cameras constantly record what comes into view, and the tapes are later played back on board ship to document major events of the dive. All the electronics run on batteries and there is no tether connecting the sub to the research vessel 2,250 meters (over one mile) above it. In other words, the ALVIN-with researchers and crew inside-is totally on its own once it's launched. Alone in the dark!

But I'm not scared of the dark; I would love the chance to go down to the vents inside i. Soon we'll be drawing straws to see which REVEL teacher gets this once-in-a-lifetime opportunity-I hope it's me!

Yours truly high above the aphotic zone,
Pat

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Dispatches from the Deep: Light and Dark in the Sea | AMNH

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Only the top 200 meters (656 feet) of the ocean get enough light to support plants. Below 1,000 meters (3,281 feet), there's complete darkness. So how do organisms on the sea floor find food?

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10 Bizarre Mariana Trench Animals That Capture The Terrifying Extremes Of Evolution

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From goblin shark to football fish and Dumbo octopus, the deep sea is one long spit-take.

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National Centers for Environmental Information (NCEI)

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While thousands of people have summited Mount Everest, the highest point on Earth, fewer than a handful have managed to explore our planet's deepest point, a location known as the Challenger Deep in the Pacific Ocean's Mariana Trench.

A Trench of Epic Proportions

Located in the western Pacific Ocean, east of the Philippines, the Mariana Trench is a crescent-shaped scar in Earth's crust that measures more than 1,500 miles (2,550 kilometers) long and 43 miles (69 kilometers) wide on average. If you cut Mount Everest off at sea level and put it on the ocean bottom in the Challenger Deep, there would still be over a mile of water over the top of it.

The Mariana Trench was formed through a process called subduction. Earth's crust is made up of comparably thin plates that "float" on the molten rock of the planet's mantle. While floating on the mantle, the edges of these plates slowly bump into each other and sometimes even collide head-on.

When two plates crash into each other, an oceanic plate plunges downward into the mantle, while the other plate rides up over the top. This movement creates a trench where the descending oceanic plate drags down the edge of the overriding plate. This movement also creates the largest known earthquakes, which often generate tsunamis.

Today, the majority of the Mariana Trench is a U.S. protected zone as part of the Marianas Trench Marine National Monument, established in 2009.

Science Goes Deep

Part of the reason that the Challenger Deep is largely unexplored is due to hydrostatic pressure. When you enter any body of water and begin diving down from the surface, the deeper you dive the more water covers you. The more gallons of water between you and the surface, the greater the pressure on your body.

When you dive into a swimming pool and go all the way to the bottom of the deep end, you can often feel the hydrostatic pressure against your eardrums-a feeling of having them squeezed or pushed in. Magnify that feeling by thousands and you can imagine how incredible the pressure would be in the Challenger Deep with almost 7 miles of water overhead.

As challenging as it is to explore the Mariana Trench and the Challenger Deep in particular, several intrepid explorers have succeeded in this task.

The first recordings of the depth of the trench were made by the British Royal Navy Challenger expedition in 1875, using a weighted rope, which recorded a depth of 4,475 fathoms (8,184 meters; 26,850 feet).The Mariana Trench was also surveyed in 1951 by the British Survey vessel, Challenger II, which is the namesake for the Challenger Deep. In 1984, the Japanese sent a survey vessel to the Trench to collect data using a multibeam echo sounder. The sound waves sent from the echo sounder bounce off the bottom of the ocean and are plotted on a graph to make a map of the ocean bottom. This system allowed scientists to collect important environmental data without endangering a human diver. A 2010 multibeam sonar survey of the Mariana Trench by the University of New Hampshire found new seafloor features, and obtained the most precise measurement of Challenger Deep- 10,994 meters (6.8 miles), plus or minus 40 meters (.02 miles).

Most famously, in 2012, director James Cameron made a historic, solo dive down to the bottom of the Challenger Deep in a specially-designed manned submersible named DEEPSEA CHALLENGER. This expedition collected data and specimens previously unknown, leading to a wealth of scientific knowledge about one of the least known parts of our Earth.

Discover the Mariana Trench From Your Couch

You don't have to take a trip in the DEEPSEA CHALLENGER to get a glimpse of the Mariana Trench for yourself. Experts at NCEI have created visual dive animations that allow you to travel through portions of the Mariana Trench.

Along with a visual journey to the Mariana Trench, you can view a wealth of data related to the area, including multibeam bathymetry data and digital elevation models (DEMs) that illuminate seafloor features, such as seamounts and fault scarps. DEMs are a 3D representation of terrain, merging both land and seafloor. An endeavor to map the entirety of the world's ocean floor, Seabed 2030, will reveal even more seafloor features and deepen our understanding of the processes shaping the seabed.

With continued research into the deepest points of our ocean, the mysteries held in the Mariana Trench are slowly being revealed.

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The world's deepest point lies in the Pacific Ocean and has been considered a mystery for years, but scientists are taking a closer look.

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How do fish survive in the deep ocean? (mariana trench)

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Last week, scientists filmed a fish swimming at a depth of more than 8km (27,000ft), setting a new record for the deepest ever fish documented by humans.

The unknown type of snailfish of the genus Pseudoliparis was captured by an autonomous camera swimming at a depth of 8,336m (27,349ft) in the Izu-Ogasawara trench, south-east of Japan.

The previous deepest fish recorded was the Mariana snailfish ( Pseudoliparis swirei), recorded at a depth of 8,178m (26,831ft) further south between Japan and Papua New Guinea in the Mariana Trench.

Life in the deep

The hadal zone is home to a rich, if somewhat alien, ecosystem of marine life. One of the deepest dwelling creatures discovered to date was a giant amphipod (a type of crustacean closely related to a shrimp) measuring more than 8cm (3in) long, living five miles (8km) beneath the surface in the Peru-Chile Trench. Johanna Weston, a marine biologist from Newcastle University, made the startling discovery in 2018.

The deepest parts of the ocean are known as the hadal zone, named after the Greek god of the underworld, Hades.

The hadal zone, which extends from 6 to 11km (20,000 to 36,000ft), is a forbidding place, characterised by complete darkness, crushing pressure and near-freezing temperatures.

For a long time scientists believed that life in the ocean depths was impossible due to these hostile conditions, but that perception changed dramatically in 1977, when a US research team dropped a remotely operated vehicle 8,000ft (2,440m) into the Pacific Ocean to take images from hydrothermal vents, where seawater meets magma. They were astonished to find these deep-sea vents teeming with life.

Since 1977, marine scientists have discovered up to 600 never-before-seen species around these vents, including a scaly-foot gastropod, ( Chrysomallon squamiferum), a type of snail with iron armour, and a new crab named 'The Hoff' ( Kiwa tyleri) after US actor David Hasselhoff due to its hairy chest.

The Mariana snailfish (Pseudoliparis swirei) was the previous deepest fish recorded. It was discovered at a depth of 8,178m (26,831ft) (Credit: Alamy)

Scientists are intrigued by these discoveries and species' ability to survive in the extreme pressures, cold temperatures and pitch black of the hadal zone.

At the bottom of the Mariana Trench there is 1,086 bars of pressure, the equivalent of 100 elephants standing on your head, according to Abbie Chapman, a researcher at University College London who has studied creatures living around hydrothermal vents.

How can creatures thrive in such extreme environments?

Marine animals living in the hadal zone have adapted on a cellular level to enable them to withstand the oppressive conditions.
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Deep ocean discoveries

In 2019, US explorer Victor Vescovo discovered the deepest shipwreck in history: the USS Johnston, which sank in 1944 after a battle against the world's largest battleship. The wreck was discovered submerged 6km (3.7 miles) below the water off the coast of the Philippines.

Vescovo also found a plastic bag and sweet wrappers when he later descended almost 11km (seven miles) to the bottom of the Mariana Trench in the Pacific Ocean in 2019.

Creatures such as giant amphipod crustaceans and the Mariana snailfish have high concentrations of organic molecules called piezolytes (the name comes from the Greek word " piezin" which means pressure), which stop their cellular membranes and proteins from being crushed under extremely high pressure.

These molecules counteract the weight of the surrounding water column by increasing the space that proteins take up inside the organism's cells. According to deep-sea biologist Tim Shank at the Woods Hole Oceanographic Institution in Massachusetts, "it's like putting the stakes up in a tent".

Studies show that the amount of the piezolyte molecule trimethylamine N-oxide (TMAO) increases in ocean organisms in line with the depth of their habitat.

Researchers from the University of Leeds concluded in a 2022 study that TMAO acts like "an anchor point within the water network" by forming strong hydrogen bonds with water molecules. This allows the organism to resist the extreme pressure it is under.

Fish living closer to the ocean surface have a swim bladder, a gas-filled organ which allows them to remain buoyant without sinking or floating to the top. Deep-sea fish such as snailfish don't have swim bladders, as the difference in pressure between the gas-filled cavity and the water pushing in on the outside would rupture them.

Deepest ever fish to be spied on camera

Watch the film captured by scientists of a species of snailfish swimming at the deepest ever recorded. The first 15 seconds show the record breaking fish and later fish in the video are at a slightly shallower depth.
In the deep ocean there is no direct sunlight and therefore creatures cannot rely on photosynthesis to convert the Sun's energy into sugars to fuel them. Instead they use chemosynthesis to create sugars using energy released from chemical reactions occurring around the hydrothermal vents in the ocean floor. "They live off chemicals coming out of the sea floor," says Shank.

Deep-sea fish have also adapted to survive in a low-oxygen environment. Mexican cavefish, for example, have larger red blood cells that produce higher concentrations of haemoglobin, the protein that carries oxygen throughout the body, than fish that dwell near the surface, according to a 2022 study.

All these adaptations allow creatures to thrive in the dark abyss of the deep ocean, in one of the harshest environments on our planet.

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Last week, scientists filmed a fish swimming at a depth of more than 8km (27,000ft), setting a new record for the deepest ever fish documented by humans. The unknown type of snailfish of the genus Pseudoliparis was captured by an autonomous camera swimming at a depth of 8,336m (27,349ft) in the Izu-Ogasawara trench, south-east of Japan.

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The original plan for this expedition called for using Woods Hole Oceanographic's hybrid remotely operated vehicle. But sadly, Nereus was lost earlier this year.

Why It's Still a Frontier

Places deeper than 6,000 meters-known as the hadal zone-have remained a frontier mainly because so few vehicles have ever been built to penetrate such depths. A handful of robotic and manned vehicles can go to 6,500 or 7,000 meters down. But that leaves almost half the ocean's depth range inaccessible, and a collective seafloor area almost as large as Australia.

Only four vehicles have ever existed that could safely work at full ocean depth and none are currently in operation. Of course scientists have found other ways to get limited glimpses of the deepest regions, as they did on this expedition with landers. Work with this type of equipment has been critical-indeed SOI returned to the Mariana Trench in December of 2014 on a second lander project.

Ultimately researchers hope to systematically explore large swaths of the world's deepest trenches to get a more complete view of what is found there. Such work will once again be possible by 2016 as Schmidt Ocean Institute is working with Woods Hole on a new full-ocean-depth robotic vehicle.

The Big Questions

Jeff Drazen from University of Hawaii at Manoa (UH), a deep-sea fish expert, was the expedition's chief scientist, while Patricia Fryer, a geologist also at UH, was co-chief scientist. One key goal was to learn more about what animals are found in the trench, and what factors might control these animals' locations and concentrations.

Working with samples caught in traps they also studied the biochemical adaptations that allow animals to survive the crushing pressures in deep trenches, in particular, whether these animals have special compounds to protect proteins in their cells from folding improperly under the crushing pressure. One of the compounds researchers have already found that seems to help some trench dwellers withstand hadal pressure was discovered elsewhere and is being pursued as a potential treatment for Alzheimer's, which involves problems with protein folding in the brain. Other compounds discovered in the trenches might be new to science and could offer similar potential medical or other benefits.

The team also equipped one lander with modified coring devices that inserted a tube into the sediment and meaured the amount of oxygen used by the worms and other small organisms found there. This effort tied to past work suggesting that more food ends up in trenches than previously thought, and that this food-in a range of forms including falling dead phytoplankton, animals, droppings and other materials-could support more life than expected. Food concentrations might also determine where more animals congregate. The oxygen consumption rates offered a measure of the abundance and activity of sediment dwellers that can in turn be compared to location and sediment data to look for patterns in the ways that animals are distributed.

Another lander was equipped with a rock grabber that allowed the team to collect samples that can help answer key geological questions. Trenches form at the places where tectonic plates run into each other, with one falling, or being subducted, underneath the other. That process, along with associated microbial activity, plays important roles in the release and consumption of carbon and minerals. Such cycling is, for instance, a critical factor in the ocean's ability to absorb carbon dioxide from the atmosphere.

Much of our understanding of these processes, despite their importance, remains theoretical because they occur so deep that opportunities for study have been extremely rare. Rock and sediment sample analyses could either confirm some of the current understanding of these processes, or reveal new questions scientists need to ask.

Trench subduction zones are also the sites of earthquakes that at times spawn devastating tsunamis. Observations and sample analyses could also help scientists better understand factors tied to these events.

The Bigger Picture

The Falkor expedition was planned as part of the international Hadal Ecosystems Studies program, led by Woods Hole Oceanographic's Tim Shank, who was part of the Mariana Trench team.

The Mariana Trench expedition also included researchers from Whitman College, the University of Aberdeen's Oceanlab, New Zealand's National Instiute of Water and Atmospheric Research, the UK's Natural Environment Research Council, and the National Oceanography Centre, also in the UK. The cruise ran from November 9 to December 9, 2014. Cclick on the buttons in the upper left corner to follow the Cruise Log and the Expedition Map.

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Exploring the Mariana Trench - Schmidt Ocean Institute

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The very deepest reaches of the sea are one of the planet's last true frontiers. In November, RV Falkor sailed to the Mariana Trench with a group of biologists and geologists to conduct a new study of one of the deepest places in the world.

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The deepest parts of our oceans, the region between 6000 and 11 0000 m depth, is known as the hadal zone, and it represents some of the most active and diverse marine habitat on Earth.

Many studies of the hadal zone focus on the conspicuous, gigantic trenches formed by shifting tectonic plates, known as subduction zones. Each of these trenches was thought to represent isolated environments, separated from each other by areas of much shallower water depths.

For decades, researchers studying the hadal zone have had to cope with the technical challenges of working at such great depth. This means understanding of these traditionally difficult to study regions has lagged behind the overlying, shallower water ecosystems. New technologies are changing this imbalance, and there are now more opportunities to explore and study the planet's most extreme environment; the hadal zone included.

Understanding more about these deep oceans - some of the most remote and inaccessible habitats on Earth - is crucial for the regulation of global climate and for our understanding of biogeochemical cycles. They provide insights into hazards from submarine landslides and large earthquakes, and will provide invaluable baseline data as human exploration for raw materials ventures into ever deeper waters.

In a recently published study, ' Hadal zones of the North-west Pacific Ocean ', led by Newcastle University in collaboration with BGS, scientists attempted to evaluate the true extent of the deepest marine ecosystem by focusing on the North-west Pacific Ocean.

A number of large, subduction trenches are located here, including the deepest point on Earth (Challenger Deep) in the Mariana Trench, a crescent-shaped, 2550 km-long subduction zone that includes the Volcano Trench. At 10 925 m deep, it would immerse Mount Everest with still more water above it and could house 34 Eiffel Towers stacked on top of each other.

Whilst subduction trenches, like those that make up the Pacific 'Ring of Fire', are obvious hadal ecosystems, this study explored other geological features such as fracture zones and broad ocean basins. These features, although numerous, are less prominent and are often overlooked.

By evaluating the frequency and distribution of these lesser-known smaller features, the researchers conclude that, in the North-west Pacific, the total hadal area is four times larger than that of trenches alone - roughly equivalent to the size of Alaska, Texas and Montana combined.

In fact, it makes up a staggering 2 793 011 km ²; an area considerably larger than the 686 114 km ² accounted for by subduction trenches alone.

Having previously thought the Mariana Trench to be one continuous hadal habitat, the scientists discovered it is in fact five isolated areas, with the most northern being what Russian scientists used to call the Volcano Trench.

The study went on to identify that there are no physical partitions either north or south of the Japan Trench to isolate it from the neighbouring Kuril-Kamchatka or Izu-Bonin trenches, and so it can be concluded that it forms one continuous hadal habitat.

The Mariana-Volcano chain of trenches is more complex than expected. This study proves that there are actually four topographic highs that partition the hadal areas of this subduction zone within what has previously been considered by some to be a single feature.

From a habitat perspective, it means there are five physically isolated hadal habitats making up the Mariana-Volcano complex, which means that the genetic flow between hadal populations of species endemic to these extreme depths will be limited.

This means that hadal depths represent a diversity of species, each potentially carrying hidden secrets that will be important for us to discover and learn from.
Heather Stewart, BGS Marine Geologist and co-author of the study.

The study also revealed that the Yap Trench actually comprises two separate hadal areas.

However, the Izu-Bonin, Japan and Kuril-Kamchatka trenches lack a biologically significant shallow-water divide. These three trenches seem to represent one continuous hadal corridor.

Aside from advancing geological understanding, scientists are particularly interested in these findings from a biological perspective. They are especially keen to understand whether geographically isolated populations may have reduced levels of gene flow between them, causing them to diverge morphologically.

By studying the geomorphology, or shape, of the sea floor, we have revealed which trenches form continuous hadal habitats and which are completely isolated from each other. When you include the previously overlooked hadal areas located away from these subduction zones, the total hadal ecosystem is potentially massive.
Heather Stewart.

In the most recent studies, two main organisms have been used to study hadal endemism: amphipods and fishes.

Amphipods are typically collected consistently in large numbers using baited traps whilst fish are more often observed on baited cameras.

Current theories suggest that most amphipods form isolated populations cannot readily cross abyssal partitions.

With a few rare exceptions, this is also believed to be the case for dominant fish species sampled from depths below 6000 m.

This would explain why some trenches are host to species endemic to that area and why we sometimes see populations evolve to become distinct species between neighbouring trenches, something which is more pronounced with increasing distance between trenches.

These studies highlight that, whilst non-subduction features are an overlooked minor fraction of the total hadal area, they are essential to our understanding of the ecological and evolutionary dynamics across the hadal zone.
Alan Jamieson, marine biologist at Newcastle University and lead author of the study.

One thing our scientists know for certain is that their continued efforts to study seabed geomorphology is crucial to understanding the connectivity between hadal zones.

And we should continue to explore the mysteries of these hadal depths, because our relationship with even the deepest reaches of our maritime environment underpins life on earth.
Media Contact: Further studies British Geological Survey

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Uncovering secrets of the Mariana Trench - British Geological Survey

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Scientists have discovered that the true extent of the deepest parts of our oceans may be far larger than they previously thought.

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location of the mariana trench

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Doug Bartlett was there to explore an alien world, possibly filled with unknown marine life. Kevin Hardy was there to fulfill a lifelong dream of developing instruments he designed to reach the world's deepest point. After years of meticulous preparations they waited. Finally, they were part of a team that made history.

Launched in a submarine roughly 200 miles southwest of Guam, filmmaker James Cameron touched the depths of the Mariana Trench, the deepest spot in the world, at 2:52 p.m. (PDT) on March 25, marking humanity's first return to the storied location in more than 50 years.

Inside Deepsea Challenger, his specially designed submersible, Cameron descended 35,756 feet (6.77 miles) in two hours and 36 minutes to become the first solo diver in history to reach the Pacific Ocean's "Challenger Deep."

Scripps Institution of Oceanography at UC San Diego has been the Deepsea Challenge's primary science collaborator, culminating nearly a decade of interaction with Cameron in developing new ways to explore and study the deepest parts of the oceans.

"The Deepsea Challenge expedition is highlighting in stunning and dramatic fashion the alien-like environments that exist at great depth," said Bartlett, a Scripps marine microbiologist and chief scientist of the voyage. "Hadal (existing at depths greater than 20,000 feet) life forms are the part of the earth's biology that are least understood."

After leaving the team to attend the London premiere of "Titanic 3D," Cameron intends to rejoin the expedition and continue diving in the Mariana Trench, a location where one of the planet's massive tectonic plates is moving under, or "subducting," another. The team hopes the upcoming dives will return with bounties of samples and extractions for Bartlett and other scientists to study.

Scripps' history in exploring the deepest regions of the ocean go back to the 1950s and '60s, when Scripps research geologist Robert Fisher meticulously mapped the Mariana Trench's deepest points. He employed innovative sounding techniques to firmly establish that Challenger Deep in the Mariana Trench is the deepest point in the world's oceans. In 1952 Fisher identified Horizon Deep in the Tonga Trench as the second-deepest point in the oceans and the deepest spot in the Southern Hemisphere.

This work set the stage for Swiss oceanographer Jacques Piccard and U.S. Navy Lieutenant Don Walsh's famous dive aboard the bathyscaphe Trieste in the first manned voyage to the bottom of Challenger Deep on January 23, 1960.

Also aboard the Deepsea Challenge expedition is Kevin Hardy, a Scripps engineer who has developed Deep Ocean Vehicles (DOVs) with a capability to probe the deepest portions of the ocean and retrieve new information for science and society. DOVs, also known as "landers" because they descend from the surface to land upright on the seafloor, are scheduled to be deployed in Cameron's upcoming dives.

In collaboration with Cameron's project, Scripps scientists will obtain seawater, sediment cores, and deep-sea animals, in many cases collected by deep-sea landers. These samples will enable scientists to identify new life forms. Scripps microbiologists will investigate the DNA of the samples to help understand how life evolves and adapts in the punishing extremes of the deep, as well as ascertain whether such microbes could be sources of novel natural products with potential biomedical value.

"The dark, high pressure, low temperature, and altered nutrient conditions of deep-sea environments have influenced the evolution and distribution of life in profound ways that we have yet to fully discern," said Bartlett. "We now have the tools and technology, manned and unmanned, for in-depth studies of deep life for the benefit of basic and applied science."

DOVs with sensors are equipped to collect pressure, temperature, salinity, and other physical and chemical measurements. Sampling devices can be employed to physically collect water, sediment, and marine animals. They can operate as seafloor factories, filtering water for microbes, or incubating bacterial cultures. DOVs also act as valuable testing platforms to qualify new technologies and investigate new scientific questions, carrying assorted payloads-including cameras and data loggers-quickly, inexpensively, and reliably to any place within the ocean's great volume.

A version of a DOV lander is now on display in a new exhibit, "Creatures of Light: Nature's Bioluminescence," at the American Museum of Natural History in New York City. Another is scheduled for display in the Monaco Pavilion at the upcoming Expo 2012 Yeosu Korea international exposition.

The Deepsea Challenge is a joint scientific expedition by Cameron, National Geographic, and Rolex.

In the 1950s and '60s, when Scripps research geologist Robert Fisher meticulously mapped the Mariana Trench's deepest points.

Scripps engeineer Kevin Hardy has developed Deep Ocean Vehicles (DOVs) with a capability to probe the deepest portions of the ocean and retrieve new information for science and society.

Related Video: Voyage to the Mariana Trench

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Research Highlight: Scripps Delivers Science to James Cameron's Historic Dive into the Abyss

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Doug Bartlett was there to explore an alien world, possibly filled with unknown marine life. Kevin Hardy was there to fulfill a lifelong dream of developing instruments he designed to reach the world's deepest point. After years of meticulous preparations they waited. Finally, they were part of a team that made history.

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The Mariana Trench is still somewhat of a mystery to humans above the surface. But over the years, scientists have discovered that this vast open pit holds some of the strangest marine creatures on Earth. From cute little octopuses to bone-eating worms, we are going to look at ten of the strangest creatures in the Mariana Trench.

What is the Mariana Trench?

The Mariana Trench is the deepest oceanic trench in the world. The bottom of the Mariana Trench is the " Challenger Deep ", and lies at a maximum depth of 36,037 feet (10,984 meters). The Mariana Trench is thought to have formed with the collision of two tectonic plates, and it is located in the western Pacific Ocean, around 124 miles (200 kilometers) to the east of the Mariana islands. The trench is around 1,580 miles (2,550 kilometers) long and 43 miles (69 kilometers) wide.

There are some bizarre and fascinating creatures in the Mariana trench, let's take a look at a few of them.

10 Bizarre Creatures in the Mariana Trench

Deep-sea dragonfish

The deep-sea dragonfish (sometimes known as the scaleless dragonfish) has extremely large teeth in relation to its body size, and is a ferocious predator in the depths of the Mariana Trench. The deep-sea dragonfish can create its own light with help from bioluminescence. The fish flashes its lights to attract prey and even uses the lights to signal to mates. The deep-sea dragonfish has quite a gruesome appearance with a large head and sharp, fang-like teeth that help it to grab hold of small fish and crustaceans.

Dumbo octopus

The dumbo octopus is definitely a strange deep-sea creature, but many consider it to be the cutest of all marine life with its cartoon-like appearance thanks to huge dumbo-like ears. The dumbo octopus only grows to be around 8 inches (20cm), and it has little arms which add to the cuteness. They are the deepest known species of octopus and they feed off snails, worms, and other small prey they can find on the ocean floor.

Zombie worms

Probably the creepiest known marine life in the world, the zombie worm feeds off of bones and remains of carcasses that drop to the deep ocean floor. Zombie worms do not have teeth or a stomach, so they feed by secreting an acid that dissolves bones to expose fats. They then digest these fats using symbiotic bacteria. In total, 15 species of the zombie worm have been discovered since the first sighting in 2002.

Deep-sea hatchetfish

Aptly named for its hatchet-shaped body, there are 45 known species of the deep-sea hatchetfish, all varying in size. The largest species of deep-sea hatchetfish grows to around 6 inches (12cm) long. The smaller species tend to be covered in silver scales, whereas the larger ones are more likely to be a brown or green color. Hatchetfish have tubular eyes that point upwards, which enables them to look for food that falls from above.

Frilled shark

A lot of people are scared of sharks thanks to their portrayals in the media and film. And although we disagree with this inaccurate portrayal, we have to admit that this shark is a bit scary! The frilled shark has over 300 sharp teeth, large eyes, and a wide, eel-like grin. The frilled shark feeds on cephalopods, and smaller sharks and fish, and can be found as deep as 5,200 feet (1,524 meters) deep.

Vampire squid

The spooky vampire squid is found 2,000-3,000 feet (600-900 meters) deep and has a deep red color with bioluminescent lights. When threatened, the vampire squid can shoot bioluminescent liquid that sticks to the attacker. This shocks the attacker and allows the squid to make an escape. It also makes the attacker more visible to predators. This squid definitely deserves its place on the list of strangest creatures in the Mariana Trench!

Barreleye fish

The barreleye fish (sometimes known as the spook fish) could be a contender for the strangest of all the strange creatures that can be found in the Mariana Trench. Its head is inside a transparent dome which protects it from stings when it eats its favorite meal: jellyfish. Inside the dome, the barreleye fish has large eyes that point upwards to help it look for its meals in the water overhead. It also has large nostrils at the front of the dome which are often mistaken for its eyes.

Pink see-through fantasia

This translucent sea cucumber looks like something from a horror movie, with pink colored see-through skin that shows its internal organs. The pink see-through fantasia feeds on benthic sediment on the deep ocean floor. It can use bioluminescence to coat its attacker to make them more vulnerable to predators, while also working as a deterrent.

Fangtooth fish

The fangtooth fish has huge teeth (the largest of any sea creature in relation to its body) that sit in a huge, wide mouth and make it look truly terrifying. This strange creature grows to around 6 inches (15 centimeters) and feeds on much larger fish than itself thanks to its large jaw and teeth. The fangtooth fish has limited eyesight and finds its prey by detecting movement.

Ping-pong tree sponge

Last but certainly not least on our list of strangest creatures in the Mariana Trench, we have the ping-pong tree sponge. It's an alien-looking carnivorous sponge that has hook-covered spheres to catch prey. Small crustaceans get stuck to the ping-pong shaped balls and then absorbed and slowly eaten alive. It's definitely something of nightmares!

Mariana Trench: Frequently Asked Questions

Conclusion

The Mariana Trench certainly contains some weird and wonderful marine creatures, many of which we are still discovering and observing. Which is your favorite strange creature?

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Strangest Creatures in the Mariana Trench - Scuba.com

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From cute little octopuses to bone-eating worms, we are going to look at ten of the strangest creatures in the Mariana Trench.

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Location of the Mariana Trench

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 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, the density of water is increased by 4.96%.[citation needed ] 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.

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 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 the western side of the trench.

The Pacific plate is subducted beneath the Mariana Plate, creating the Mariana trench, and (further on) the arc of the Mariana Islands, as water trapped in the plate is released and explodes upward to form island volcanoes and earthquakes.

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 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.

Research history

Ocean trenches in the western Pacific

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 ("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 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 , known as 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.[better source needed ]

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 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 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, 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 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 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 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 mi) beneath the surface.

The bathyscaphe Trieste (designed by Auguste Piccard), the first crewed vehicle to reach the bottom of the Mariana Trench[22]

As of 2022, 22 crewed descents and seven uncrewed descents have been achieved. The first was the crewed descent by Swiss-designed, Italian-built, United States Navy-owned bathyscaphe , 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 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 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 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 a mile. The titanium-shelled hydrophone was designed to withstand the immense pressure 7 mi (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 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 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). 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 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 uncrewed vehicle 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 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 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, 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 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.

Possible nuclear waste disposal site

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 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 the hadopelagic ecosystem.

References

1. ^ Gardner, James V.; Armstrong, Andrew A.; Calder, Brian R.; Beaudoin, Jonathan (2 January 2014). "So, How Deep Is the Mariana Trench?" (PDF). Marine Geodesy. 37 (1). Informa UK Limited: 1-13. Bibcode:2014MarGe..37....1G. doi:10.1080/01490419.2013.837849. ISSN 0149-0419. S2CID 128668687.

2. "Scientists map Mariana Trench, deepest known section of ocean in the world". The Telegraph. 7 December 2011. Archived from the original on 10 January 2022.

3. ^ Glud, Ronnie; Wenzhöfer, Frank; Middleboe, Mathias; Oguri, Kazumasa; Turnewitsch, Robert; Canfield, Donald E.; Kitazato, Hiroshi (17 March 2013). "High rates of microbial carbon turnover in sediments in the deepest oceanic trench on Earth". Nature Geoscience. 6 (4): 284-288. Bibcode:2013NatGe...6..284G. doi:10.1038/ngeo1773.

4. ^ Aitken, Frédéric; Foulc, Jean-Numa (2019). "Chapter 4". From deep sea to laboratory. 1 : the first explorations of the deep sea by H.M.S. Challenger (1872-1876). London. ISBN 9781786303745.

5. ^ Gaskell, Thomas F. (1960). Under The Deep Oceans: Twentieth Century Voyages of Discovery (1st ed.). Eyre & Spottiswood. p. 121.

6. ^ "The Mariana Trench - Exploration". marianatrench.com.

7. ^ Development and Construction of Launcher System of 10000m‐Class Remotely Operated Vehicle KAIKO Archived 2 April 2015 at the Wayback Machine Mitsubishi Heavy Industry

8. ^ "Inventory of Scientific Equipment aboard the R/V KILO MOANA". University of Hawaii Marine Center. Archived from the original on 13 June 2010.

9. "Mariana Trench". Earthquake Hazards Program. United States Geological Survey. 21 October 2009. Archived from the original on 18 March 2012.

10. ^ "NOAA Ocean Explorer: History: Quotations: Soundings, Sea-Bottom, and Geophysics". NOAA Ocean Exploration and Research.

11. ^ Fitzherbert, Stephanie (13 May 2019). "Deepest Submarine Dive in history, Five Deeps Expedition Conquers Challenger Deep" (PDF). The Five Deeps.

12. ^ Cheng, Xiang; Liu, Liang (10 November 2020). ""奋斗者"号载人潜水器突破万米海深 潜入全球最深海域" [The "Striver" manned submersible breaks through 10,000 meters and dives into the world's deepest waters]. China Central Television.

13. ^ "James Cameron dives deep for Avatar" Archived 18 January 2017 at the Wayback Machine, Guardian, 18 January 2011

14. ^ "James Cameron heads into the abyss" Archived 1 September 2012 at the Wayback Machine, Nature, 19 March 2012

15. ^ Woods, Michael; Mary B. Woods (2009). Seven Natural Wonders of the Arctic, Antarctica, and the Oceans. Twenty-First Century Books. p. 13. ISBN 978-0-8225-9075-0.

16. ^ Jamieson, Alan J.; Malkocs, Tamas; Piertney, Stuart B.; Fujii, Toyonobu; Zhang, Zulin (13 February 2017). "Bioaccumulation of persistent organic pollutants in the deepest ocean fauna". Nature Ecology & Evolution. 1 (3): 51. doi:10.1038/s41559-016-0051. hdl:. ISSN 2397-334X. PMID 28812719. S2CID 9192602.

17. ^ Jamieson, A. J.; Brooks, L. S. R.; Reid, W. D. K.; Piertney, S. B.; Narayanaswamy, B. E.; Linley, T. D. (28 February 2019). "Microplastics and synthetic particles ingested by deep-sea amphipods in six of the deepest marine ecosystems on Earth". Royal Society Open Science. 6 (2): 180667. Bibcode:2019RSOS....680667J. doi:10.1098/rsos.180667. ISSN 2054-5703. PMC . PMID 30891254.

18. Hafemeister, David W. (2007). Physics of societal issues: calculations on national security, environment, and energy. Berlin: Springer. p. 187. ISBN 978-0-387-95560-5.

19. ^ Kingsley, Marvin G.; Rogers, Kenneth H. (2007). Calculated risks: highly radioactive waste and homeland security. Aldershot, Hants, England: Ashgate. pp. 75-76. ISBN 978-0-7546-7133-6.

20. Branch, J. B. (1984). ^ The waste bin: nuclear waste dumping and storage in the Pacific. Ambio, 327-330.

# data[].attributes.attachment_link.description
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.

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(Image: © NASA/UNH Center for Coastal and Ocean Mapping/Joint Hydrographic Center)

The Mariana Trench is a crescent-shaped trench in the Western Pacific, just east of the Mariana Islands near Guam. The region surrounding the trench is noteworthy for many unique environments. The Mariana Trench contains the deepest known points on Earth, vents bubbling up liquid sulfur and carbon dioxide, active mud volcanoes and marine life adapted to pressures 1,000 times that at sea level.

The Challenger Deep, in the southern end of the Mariana Trench (sometimes called the Marianas Trench), is the deepest spot in the ocean. Its depth is difficult to measure from the surface, but modern estimates vary by less than 1,000 feet (305 meters).

In 2010, the Challenger Deep was pegged at 36,070 feet (10,994 m), as measured with sounds pulses sent through the ocean during a 2010 survey by the National Oceanic and Atmospheric Administration (NOAA).

In 2012, film director and deep-sea explorer James Cameron descended to the bottom of Challenger Deep, briefly reaching 35,756 feet (10,898 m) during the 2012 expedition. But he could have gone a little deeper. A high-resolution seafloor mapping survey published in 2014 by researchers from the University of New Hampshire said the Challenger Deep bottoms out at 36,037 feet (10,984 m).

The ocean's second-deepest place is also in the Mariana Trench. The Sirena Deep, which lies 124 miles (200 kilometers) to the east of Challenger Deep, is a bruising 35,462 feet deep (10,809 m).

By comparison, Mount Everest stands at 29,026 feet (8,848 m) above sea level, meaning the deepest part of the Mariana Trench is 7,044 feet (2,147 m) deeper than Everest is tall.

Protected land

The Mariana Trench is 1,580 miles (2,542 kilometers) long - more than five times the length of the Grand Canyon. However, the narrow trench averages only 43 miles (69 km) wide.

Because Guam is a U.S. territory and the 15 Northern Mariana Islands are a U.S. Commonwealth, the United States has jurisdiction over the Mariana Trench. In 2009, President George W. Bush established the Mariana Trench Marine National Monument, which created a protected marine reserve for the approximately 195,000 square miles (506,000 square km) of seafloor and waters surrounding the remote islands. It includes most of the Mariana Trench, 21 underwater volcanoes and areas around three islands.

How the trench formed

The Mariana Trench was created by the process that occurs in a subduction zone, where two massive slabs of oceanic crust collide. At a subduction zone, one piece of oceanic crust is pushed and pulled underneath the other, sinking into the Earth's mantle, the layer under the crust. Where the two pieces of crust intersect, a deep trench forms above the bend in the sinking crust. In this case, the Pacific Ocean crust is bending below the Philippine crust. [ Infographic: Tallest Mountain to Deepest Ocean Trench]

The Pacific crust, also called a tectonic plate, is about 180 million years old where it dives into the trench. The Philippine plate is younger and smaller than the Pacific plate.

"At subduction zones, the cold, dense crust sinks back into the mantle and is destroyed," said Nicholas van der Elst, a seismologist at Columbia University's Lamont Doherty Earth Observatory in Palisades, New York.

As deep as the trench is, it is not the spot closest to the center of Earth. Because the planet bulges at the equator, the radius at the poles is about 16 miles (25 km) less than the radius at the equator. So, parts of the Arctic Ocean seabed are closer to the Earth's center than the Challenger Deep.

The crushing water pressure on the floor of the trench is more than 8 tons per square inch (703 kilograms per square meter). This is more than 1,000 times the pressure felt at sea level, or the equivalent of having 50 jumbo jets piled on top of a person.

(Image credit: www.freeworldmaps.net)

Unusual volcanoes

A chain of volcanoes that rise above the ocean waves to form the Mariana Islands mirrors the crescent-shaped arc of the Mariana Trench. Interspersed with the islands are many strange undersea volcanoes.

For example, the Eifuku submarine volcano spews liquid carbon dioxide from hydrothermal vents similar to chimneys. The liquid coming out of these chimneys is 217 degrees Fahrenheit (103 degrees Celsius). At the Daikoku submarine volcano, scientists discovered a pool of molten sulfur 1,345 feet (410 m) below the ocean surface, something seen nowhere else on Earth.

Life in the trench

Recent scientific expeditions have discovered surprisingly diverse life in these harsh conditions. Animals living in the deepest parts of the Mariana Trench survive in complete darkness and extreme pressure, said Natasha Gallo, a doctoral student at the Scripps Institution of Oceanography who has been studying the video footage from Cameron's 2012 expedition.

Food in the Mariana Trench is extremely limited, because the deep gorge is far from land. Leaves, coconuts and trees rarely find their way into the bottom of the trench, Gallo said, and dead plankton sinking from the surface must drop thousands of feet to reach Challenger Deep. Instead, some microbes rely on chemicals, such as methane or sulfur, while other creatures gobble marine life lower on the food chain.

The three most common organisms at the bottom of the Mariana Trench are xenophyophores, amphipods and small sea cucumbers (holothurians), Gallo said.

The single-celled xenophyophores resemble giant amoebas, and they eat by surrounding and absorbing their food. Amphipods are shiny, shrimplike scavengers commonly found in deep-sea trenches. The holothurians may be a new species of bizarre, translucent sea cucumber.

"These are some of the deepest holothurians ever observed, and they were relatively abundant," Gallo said.

Scientists have also identified more than 200 different microorganisms in mud collected from the Challenger Deep. The mud was brought back to labs on dry land in special canisters, and is painstakingly kept in conditions that mimic the crushing cold and pressure. [Video: Dive Deep: Virtual Tour of the Mariana Trench]

During Cameron's 2012 expedition, scientists also spotted microbial mats in the Sirena Deep, the zone east of the Challenger Deep. These clumps of microbes feed on hydrogen and methane released by chemical reactions between seawater and rocks.

However, a deceptively vulnerable-looking fish is not only right at home here, it's also one of the region's top predators. In 2017, scientists reported they had collected specimens of an unusual creature, dubbed the Mariana snailfish, which lives at a depth of about 26,200 feet (8,000 m). The snailfish's small, pink and scaleless body hardly seems capable of surviving in such a punishing environment, but this fish is full of surprises, researchers reported in a new study. The animal appears to dominate in this ecosystem, going deeper than any other fish and exploiting the absence of competitors by gobbling up the plentiful invertebrate prey that inhabit the trench, the study authors wrote.

Pollution in the deep

Unfortunately, the deep ocean acts as a potential sink for discarded pollutants and litter. In a recent study, a research team led by Newcastle University shows that human-made chemicals that were banned in the 1970s are still lurking in the deepest parts of the ocean.

While sampling amphipods (shrimp-like crustaceans) from the Mariana and Kermadec trenches, the researchers discovered extremely high levels of persistent organic pollutants (POPs) in the organisms' fatty tissues. These included polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), chemicals commonly used as electrical insulators and flame retardants, according to a study published in the journal Nature Ecology & Evolution. These POPs were released into the environment through industrial accidents and landfill leakages from the 1930s until the 1970s when they were finally banned.

"We still think of the deep ocean as being this remote and pristine realm, safe from human impact, but our research shows that, sadly, this could not be further from the truth," said lead author Alan Jamieson of Newcastle University in a press release.

In fact, the amphipods in the study contained levels of contamination similar to that found in Suruga Bay, one of the most polluted industrial zones of the northwest Pacific.

Since POPs cannot degrade naturally, they persist in the environment for decades, reaching the bottom of the ocean by way of contaminated plastic debris and dead animals. The pollutants are then carried from creature to creature through the ocean's food chain, eventually resulting in chemical concentrations far higher than surface level pollutions.

"The fact that we found such extraordinary levels of these pollutants in one of the most remote and inaccessible habitats on earth really brings home the long term, devastating impact that humankind is having on the planet," said Jamieson in the press release.

The researchers say the next step will be to understand the consequences of this contamination and what it is doing to the ecosystem as a whole.

Humans and the trench

In 1875, the trench was discovered by the HMS Challenger using recently invented sounding equipment during a global circumnavigation.

In 1951, the trench was sounded again by HMS Challenger II. Challenger Deep was named after the two vessels.

In 1960, a "deep boat" named Bathyscaphe Trieste reached the bottom of Challenger Deep. It was the first vessel to do so and was manned by U.S. Navy Lt. Don Walsh and Swiss scientist Jacques Piccard.

In 1995, the Japanese unmanned submarine Kaiko gathered samples and useful data from the trench.

In 2009, the United States sent a hybrid remotely operated vehicle, Nereus, to the floor of Challenger Deep. The vehicle remained on the seabed for nearly 10 hours.

In 2012, Cameron manned the Deepsea Challenger and reached the seabed but was unable to capture any photos due to a hydraulic fluid leak. The submersible was later donated to the Woods Hole Oceanographic Institution.

- Additional reporting by Elizabeth Dohrer and Traci Pedersen, LiveScience contributors
Additional resources

# data[].attributes.attachment_link.description
(Image: © NASA/UNH Center for Coastal and Ocean Mapping/Joint Hydrographic Center) The Mariana Trench is a crescent-shaped trench in the Western Pacific, just east of the Mariana Islands near Guam. The region surrounding the trench is noteworthy for many unique environments.

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mapped mariana trench from exhibition

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Scientists map Mariana Trench, deepest known section of ocean in the world

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Scientists have been able to map the Mariana Trench, the deepest known section of ocean in the world, in greater detail than ever before.

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Mariana Trench, deep-sea trench in the floor of the western North Pacific Ocean, the deepest such trench known on Earth, located mostly east as well as south of the Mariana Islands. It is part of the western Pacific system of oceanic trenches coinciding with subduction zones-points where two adjacent tectonic plates collide, one being forced below the other. An arcing depression, the Mariana Trench stretches for more than 1,580 miles (2,540 km) with a mean width of 43 miles (69 km). The greatest depths are reached in Challenger Deep, a smaller steep-walled valley on the floor of the main trench southwest of Guam. The Mariana Trench, which is situated within the territories of the U.S. dependencies of the Northern Mariana Islands and Guam, was designated a U.S. national monument in 2009.

Measuring the greatest depths in the Mariana Trench is an exceedingly difficult task, given the technical challenges of delivering instrumentation to such a remote location and then obtaining accurate readings. The first attempt was made in 1875 during the Challenger Expedition (1872-76), when a sounding of 26,850 feet (8,184 metres) was obtained near the southern end of the trench. In 1899 Nero Deep (31,693 feet [9,660 metres]) was discovered southeast of Guam. That sounding was not exceeded until a 32,197-foot (9,813-metre) hole was found in the vicinity 30 years later. In 1957, during the International Geophysical Year, the Soviet research ship Vityaz sounded a new world record depth of 36,056 feet (10,990 metres) in Challenger Deep. That value was later increased to 36,201 feet (11,034 metres). Since then several measurements of the Challenger Deep have been made, using increasingly sophisticated electronic equipment. Notable among these is the depth of 35,840 feet (10,924 metres) reported by a Japanese expedition in 1984 and one of 36,070 feet (10,994 metres) obtained by a U.S. research team in 2011. In addition, another deep hole-originally called HMRG Deep (for Hawaii Mapping Research Group, the discoverers of the location) and later renamed Sirena Deep-is situated south of Guam and east of Challenger Deep. First encountered in 1997, its depth has been reported variously as 34,911 and 35,463 feet (10,641 and 10,809 metres).

The first descent to the bottom of the Mariana Trench took place on January 23, 1960. The French-built U.S. Navy-operated bathyscaphe Trieste-with Swiss ocean engineer Jacques Piccard (who helped his father, Auguste Piccard, design the bathyscaphe) and U.S. naval officer Don Walsh aboard-made a record dive to 35,814 feet (10,916 metres) in Challenger Deep. The next person to descend into that location did so more than 50 years after Piccard and Walsh. On March 26, 2012, Canadian filmmaker James Cameron piloted the submersible Deepsea Challenger (which he had helped design) to 35,756 feet (10,898 metres), in the process establishing a new world record depth for a solo descent.

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Mariana Trench | Depth, Location, Facts, Maps, & Pictures

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Mariana Trench (Marianas Trench), deepest of the world's deep-sea trenches. It stretches for more than 1,580 miles (2,540 km) with a mean width of 43 miles (69 km) and is part of the western Pacific system of oceanic trenches coinciding with subduction zones. Read here to learn more about the Mariana Trench.

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Ten Years of Scientific Research Conducted in the Mariana Trench: A brief summary

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DEAR Friends of the Mariana Trench, When we are out and about in the community when often make references to the increased volume of research in our Mariana Trench Marine National Monument. In a recent board discussion, we thought you might enjoy a few more details "about all this additional research" that has taken place since the declaration of the monument.