It then slid 2/3-mile down the side of an extinct volcano, finally coming to rest on a notch on the underwater mountain.

Only the tops of these underwater mountains and high plateaus are exposed as islands.

Seamounts - underwater mountains rising at least 1000 metres above the sea floor.

Samples extracted from these underwater mountains indicate that all were once islands.

Manihiki sits atop an underwater mountain rising 4000 m above the ocean floor.

Suddenly a giant underwater mountain sprouted up 10,000 feet where the old chart had shown only a vague bump.

You come upon it suddenly, rising out of the water like the tip of some vast underwater mountain (which, in fact, it is).

A guyot is an underwater mountain or seamount with a flat top.

The underwater mountain is named after the former Komahashi district of the Saikaidō region.

In addition, his name is the generic term for flat-topped underwater mountains rising from the ocean floor.