What is a deep ocean trench simple definition?
Ocean trenches are long, narrow depressions on the seafloor. These chasms are the deepest parts of the ocean—and some of the deepest natural spots on Earth.
What is an example of a deep ocean trench?
The Challenger Deep, the deepest part of the ocean, is found in the Pacific Ocean near Guam. Along the West coast of South America there is the Peru-Chile trench, and even in the Atlantic, which doesn’t have as many trenches, there is the Puerto Rico Trench, which is an impressive 28,232 feet deep and 175 miles long.
What is a deep ocean trench quizlet?
Ocean trenches are deep sections of the ocean where an oceanic plate is usually sinking below a continental plate. They are formed in the subduction zone as the denser oceanic plate is subjected under the continental plate.
What are deep trenches called?
oceanic trench
Deep-sea trench, also called oceanic trench, any long, narrow, steep-sided depression in the ocean bottom in which occur the maximum oceanic depths, approximately 7,300 to more than 11,000 metres (24,000 to 36,000 feet). They typically form in locations where one tectonic plate subducts under another.
Why are most trenches found in the Pacific Ocean?
Why are most oceanic trenches found in the Pacific Ocean? The Pacific Ocean is shrinking and plates are descending below surrounding plates along its edges, hence the creation of trenches.
What happens at a deep ocean trench?
Ocean trenches are steep depressions in the deepest parts of the ocean [where old ocean crust from one tectonic plate is pushed beneath another plate, raising mountains, causing earthquakes, and forming volcanoes on the seafloor and on land.
What are the 5 deepest trenches in the world?
The Five Deeps Expedition was the first to reach the deepest point in each of the Earth’s five oceans: the Puerto Rico Trench in the Atlantic, South Sandwich Trench in the Southern Ocean, Java Trench in the Indian Ocean, Challenger Deep in the Pacific and Molloy Deep in the Arctic.
How are deep-ocean trenches created?
Trenches are formed by subduction, a geophysical process in which two or more of Earth’s tectonic plates converge and the older, denser plate is pushed beneath the lighter plate and deep into the mantle, causing the seafloor and outermost crust (the lithosphere) to bend and form a steep, V-shaped depression.
Where do deep-ocean trenches occur quizlet?
Where does a Deep-Ocean Trench occur? A convergent plate boundary where one continental plate and one oceanic plate collide.
Why is Mariana Trench so deep?
One reason the Mariana Trench is so deep, he added, is because the western Pacific is home to some of the oldest seafloor in the world—about 180 million years old. Seafloor is formed as lava at mid-ocean ridges. When it’s fresh, lava is comparatively warm and buoyant, riding high on the underlying mantle.
Which ocean has the most trenches Why?
the Pacific Ocean
Why are most oceanic trenches found in the Pacific Ocean? The Pacific Ocean is shrinking and plates are descending below surrounding plates along its edges, hence the creation of trenches.
Which ocean has the most trenches?
Trenches are long, narrow and very deep and, while most are in the Pacific Ocean, can be found around the world. The deepest trench in the world, the Mariana Trench located near the Mariana Islands, is 1,580 miles long and averages just 43 miles wide.
What characteristics define a deep ocean trench?
Trenches, Deep-sea one of the most characteristic elements of the relief of the transitional zone between a continent and the ocean, consisting in a long, narrow lowering in the ocean floor to a depth of over 6,000 m. Deep-sea trenches are usually located on the outer (ocean) side of the mountain ranges of the island arcs.
What happens at deep ocean trenches?
Older sections of the sea floor have deeper trenches, which happens because heavier rock tends to sink over time . The fact that these deep-ocean trenches existed at all remained a secret until well into the 20th century. That’s because there were no vessels that could explore those regions. Visiting them requires specialized submersible craft.
What animals live in deep sea trenches?
Animals that live in ocean trenches are quite diverse. They range from bacteria and microorganisms to fish, jellyfish, crabs, lobsters, and octopi. More specifically, tubeworms and deep-sea angler fish are two examples.
What causes the formation of deep ocean trenches?
Deep ocean trenches are formed when a continental plate descends underneath an oceanic plate. This is commonly a process of plate tectonics. The Earth’s lithosphere is divided into 17 large tectonic plates and about 20 smaller plates, all of which are continuously moving with respect to each other.