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How do volcanic eruptions form seamounts and guyots?

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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.

Seamounts and guyots are both products of submarine volcanism, which occurs when molten rock is discharged onto the ocean floor, often at mid-oceanic ridges or over tectonic hot spots.12

Seamounts

A seamount is a large submarine volcanic mountain that rises at least 1,000 meters above the surrounding seafloor. These structures typically form from the extrusion of basaltic lava, often along linear rifts. As tectonic plates migrate, these volcanoes can form chains of varying ages, marking the path of the plate over a stationary volcanic source.32

Guyots

A guyot is a flat-topped seamount. Their formation involves a multi-stage process:13
* Initial Growth: They originate as volcanic islands at the shallow crests of ridges or rises.1
* Erosion: Once these volcanoes reach the surface, they are truncated and flattened by wave [erosion].14
* Subsidence: As the seafloor moves away from the ridge crest, the crust cools, becomes denser, and sinks. This causes the once-flat islands to subside deep below the ocean surface, becoming guyots.14