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How deep are abyssal plains?

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World map highlighting major features of the ocean basins, including trenches, ridges, basins, and plateaus labeled throughout the Pacific, Atlantic, Indian, Southern, and Arctic Oceans. Continents are shown with shaded terrain, and prominent undersea features such as the Mid-Atlantic Ridge, Mariana Trench, and Kerguelen Plateau are marked across the map. — ocean basin Major features of the ocean basins.

Abyssal plains are vast, flat areas of the seafloor typically found at depths ranging from 3,000 to 6,000 meters (10,000 to 20,000 feet). These regions are generally located adjacent to continental margins and are characterized by their remarkably level topography, which varies in depth by only 10 to 100 centimeters per kilometer of horizontal distance.1

The formation of these plains is primarily driven by the accumulation of land-derived sediment transported by turbidity currents. This process effectively buries preexisting irregular seafloor topography, creating the smooth, featureless surfaces observed today. While they are most common and extensive in the Atlantic Ocean, they occur in various deep-sea basins worldwide, such as the Colombian Abyssal Plain, which reaches a maximum depth of 4,347 meters (14,261 feet).123