What does deep ocean trench mean

These dark, once-mysterious canyons plunge down as far as 11, meters 36, feet into our planet's crust. That's so deep that if Mount Everest were placed at the bottom of the deepest trench, its rocky peak would be 1.

Technically, tenches are long, narrow depressions on the seafloor. The harbor fantastic life forms not seen on the surface, animals and plants that thrive in the extreme conditions of the trenches. It has only been in the past few decades that humans could even consider venturing that deep to explore. Trenches are part of the seafloor topology that also contains volcanoes and mountain peaks higher than any on the continents.

They form as a result of tectonic plate motions. The study of Earth science and tectonic plate motions , explains the factors in their formation, as well as the earthquakes and volcanic eruptions that occur both underwater and on land. Deep layers of rock ride atop Earth's molten mantle layer. As they float along, these "plates" jostle up against each other.

In many places around the planet, one plate dives under another. The boundary where they meet is where deep ocean trenches exist. For example, the Mariana Trench, which lies beneath the Pacific Ocean near the Mariana island chain and not far from the coast of Japan, is the product of what's called "subduction. That combination of sinking and melting formed the Mariana Trench. Ocean trenches exist in all the world's oceans.

Most but not all are directly related to subduction actions or plates moving apart, which take millions of years to occur. For example, the Diamantina Trench formed when Antarctica and Australia pulled apart many millions of years ago. That action cracked Earth's surface and the resulting fracture zone became the trench.

Most of the deepest trenches are found in the Pacific Ocean, which overlies the so-called "Ring of Fire". That region gets the name due to tectonic activity that also spurs the formation of volcanic eruptions deep beneath the water. Kirstin also has ongoing projects in the Arctic and on coral reefs in Palau. Her work frequently takes her underwater using remotely operated vehicles and SCUBA and carries her to the far corners of the world.

What are ocean trenches? How are trenches formed? What is it like in a trench? How does life survive there? What do we know about trenches? Why are ocean trenches important? What can ocean trenches tell us about earthquakes? What can ocean trenches tell us about human health? What can ocean trenches tell us about Earth's climate?

What's next for trench exploration and discovery? July 22, Life at Rock Bottom This digital photo essay brings you the forms, figures, and facts of life more than a mile and half deep. Ocean Robots: Challenger Deep. Nereus in the Challenger Deep. Related Topics Hydrothermal Vents. Mid-ocean Ridges. Natural Oil Seeps. We use cookies to analyze site usage and improve user experience. By continuing on this site, you consent to their use.

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Any interactives on this page can only be played while you are visiting our website. You cannot download interactives. These tectonic plates rest upon the convecting mantle, which causes them to move. The movements of these plates can account for noticeable geologic events such as earthquakes, volcanic eruptions, and more subtle yet sublime events, like the building of mountains.

Teach your students about plate tectonics using these classroom resources. Students read about the establishment of the Mariana Trench Marine National Monument and discuss why it is important to preserve the Mariana Trench and surrounding area. Students locate the Mariana Trench on a map, discuss who has jurisdiction over it, and identify the challenges of exploring the deepest place on Earth. Join our community of educators and receive the latest information on National Geographic's resources for you and your students.

Skip to content. Twitter Facebook Pinterest Google Classroom. Encyclopedic Entry Vocabulary. Links map The Peru-Chile Trench stretches along the west coast of South America, where the oceanic crust of the Nazca plate is subducting beneath the continental crust of the South American plate.

Visit our MapMaker Interactive map to learn more. Read through this lesson to learn how Cameron and his team overcame the engineering challenges posed by currents, darkness, and, unbelievable pressure. Ocean trench es are long, narrow depression s on the seafloor. These chasm s are the deepest parts of the ocean—and some of the deepest natural spots on Earth. In particular, ocean trenches are a feature of convergent plate boundaries, where two or more tectonic plate s meet.

At many convergent plate boundaries, dense lithosphere melts or slides beneath less-dense lithosphere in a process called subduction , creating a trench. Ocean trenches occupy the deepest layer of the ocean, the hadalpelagic zone. The intense pressure, lack of sunlight, and frigid temperatures of the hadalpelagic zone make ocean trenches some of the most unique habitat s on Earth.

When the leading edge of a dense tectonic plate meets the leading edge of a less-dense plate, the denser plate bends downward. This place where the denser plate subducts is called a subduction zone. Oceanic subduction zones almost always feature a small hill preceding the ocean trench itself. This hill, called the outer trench swell , marks the region where the subducting plate begins to buckle and fall beneath the more buoyant plate.

Some ocean trenches are formed by subduction between a plate carrying continental crust and a plate carrying oceanic crust. Continental crust is always much more buoyant than oceanic crust, and oceanic crust will always subduct.

Ocean trenches formed by this continental-oceanic boundary are asymmetric al. You don't bag something and leave it by the trench while you go back to the truck for your lunch. Early airpower theorists were not only repelled by trench warfare. The guys that I was partnering with early on wanted the logo to be a guy opening his trench coat. The goal was to get a human being to the bottom of the Mariana Trench for the first time since Cameron was a 5-year-old.