Ocean floor topography and its features
Published on 02 Feb 2025
The ocean floor, also known as the seabed or seafloor, is a diverse and dynamic landscape that exhibits various features and topographical characteristics.
Major relief features
Continental shelf: The Shallowest part of the ocean with an average gradient of 10 or less which ends at a very steep slope called shelf break. They are a major source of fossil fuels.
Example: Siberian shelf of Arctic Ocean
Continental slope: Steeper sections of the ocean floor that connect the continental shelf to the deep ocean floor. These are transition zones between the continental shelf and the deep ocean. Canyons and trenches are observed in this region.
Example: The Blake Plateau off the southeastern United States and the continental borderland off southern California
Deep sea plain/ abyssal plains: Flat and smooth expanses of the ocean floor found at depths typically greater than 4,000 meters. Comprise the largest part of the ocean floor, and are often covered with sediments.
Example: Sohm abyssal plains
Oceanic deeps and trenches: Deep, elongated depressions in the ocean floor, often associated with subduction zones. These form some of the deepest points in the ocean.
Example: The Mariana Trench in the western Pacific Ocean, containing the Challenger Deep, the deepest known point in the Earth's oceans.
Minor relief features
Mid-oceanic ridges: Composed of two chains of mountains separated by a large depression seen in sites of seafloor spreading, where tectonic plates are moving apart.
Example: The Mid-Atlantic Ridge.
Sea mount: Mountain with pointed summits rising from the sea floor but do not reach the surface of the ocean.
Example: Emperor Sea Mount in the Pacific Ocean.
Submarine canyons: Deep, steep-sided valleys cut into the continental slope and sometimes the continental shelf.
Example: Monterey Canyon Off the coast of central California, USA.
Guyots: Flat-topped seamounts that have been eroded and submerged. It often has a circular or elliptical shape.
Example: The Gardner Pinnacles in the Pacific Ocean.
Atoll: Low islands found in the tropical oceans consisting of coral reefs surrounding a central depression.
Example: The Great Barrier Reef.