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Why does the Pacific Ocean have many abyssal hills on its floor?

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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.

The Pacific Ocean features a high concentration of abyssal hills on its floor primarily because it receives a significantly smaller supply of continental sediment compared to the Atlantic Ocean.1

In many ocean basins, abyssal plains—which are formed by the accumulation of sediment—cover the underlying topography. However, the Pacific is characterized by numerous trenches and local rises that effectively isolate the main ocean floor from the continents, preventing the seaward transport of sediment that would otherwise bury these features. As a result, between 80 and 85 percent of the Pacific abyssal floor remains exposed and is occupied by these hills.1

These hills are constructed through volcanism and block faulting at spreading centres, processes that are fundamental to the creation of the oceanic crust. While they are present throughout most of the world's ocean floors, the lack of sediment burial makes them a dominant feature of the Pacific landscape.1