What are the flat-topped volcanic structures located on floor of deep ocean basin?

The flat-topped volcanic structures located on the floor of deep ocean basins are called seamounts. Seamounts are underwater mountains that rise from the seafloor but do not reach the surface of the ocean. They are typically conical in shape and can range in size from a few hundred meters to several kilometers in diameter. Seamounts are formed by volcanic activity and are often found in clusters or chains along tectonic plate boundaries. The flat tops of seamounts are often the result of erosion by wave action and currents.