Harvey Guyot

A guyot is a flat-topped undersea mountain of volcanic origin, sitting isolated on the deep ocean floor. Harvey Guyot is one such feature, hosting benthic (seafloor) habitats on its plateau and flanks.

The term was coined by Princeton geologist Harry Hammond Hess in the 1940s, based on the flat-topped seamounts he identified from World War II-era echo-sounding surveys. He named them after Arnold Henry Guyot, the 19th-century Swiss-American geologist, whose name also graces Princeton's Guyot Hall.

It began as a volcano, likely built over a hotspot, whose summit was worn down to sea level by waves and erosion. As the tectonic plate carried it away and it subsided, the flattened volcanic remnant sank to the deep ocean floor, a process documented across Pacific seamount chains like the Emperor seamounts.

Guyots provide hard volcanic substrate that supports distinct deep-sea communities, including cold-water corals, sponges, and other suspension feeders. These elevated seamount habitats are often biologically richer than the surrounding abyssal sediment plains.