You are probably looking for "trench".
It is known as a trench, which is the lower part of the ocean. The deepest trench is the Marina Trench.
A canyon.
A submarine canyon is a deep, steep-sided valley cut into the seabed of the continental slope, often formed by underwater currents. It can be a conduit for sediment transport from the shelf to the deep ocean.
It's often called a trench.
- Chasm - Canyon - Ravine - Gorge
It could be called a trench, crevice, ocean ridge, or abyss.
A deep ocean trench is a deep underwater canyon. It is found at the deepest parts of the ocean. It is long, thin, and has steep sides.
A is like a plain except that it is cut by a steep canyon?
A is like a plain except that it is cut by a steep canyon?
It is a Canyon as in the Grand Canyon.
It is a Canyon as in the Grand Canyon.
A large underwater area between continents is called a submarine canyon. These are deep, steep-sided valleys cut into the seafloor by turbidity currents, often connecting continental shelves to the deep ocean. They can be thousands of meters deep and hundreds of kilometers long.