how are these chain of mountains formed?
Formed millions of years ago by volcanism, they have since subsided far below sea level. This long chain of islands and seamounts extends thousands of kilometers northwest from the island of Hawaii.
Grouping
Formed millions of years ago by volcanism, they have since subsided far below sea level. This long chain of islands and seamounts extends thousands of kilometers northwest from the island of Hawaii.

what is a chain of underwater mountains called Seamount what can you tell about its geographic features? Seamounts can be found in every ocean basin in the world, distributed extremely widely both in space and in age. A seamount is technically defined as an isolated rise in elevation of or more from the surrounding seafloor, and with a limited summit area, of conical form.
They are typically formed from extinct volcanoes that rise abruptly and are usually found rising from the seafloor to in height Volcanoes near plate boundaries and mid-ocean ridges are built by decompression melting of rock in the upper mantle. They are typically formed from extinct volcanoes that rise abruptly and are usually found rising from the seafloor to in height.
Seamount Seamount Seamount
Introduction Geochemistry and evolution Introduction
Seamounts are typically formed from extinct volcanoes that rise abruptly and are usually found rising from the seafloor to in height. Most seamounts are built by one of two volcanic processes, although some, such as the Christmas Island Seamount Province near Australia, are more enigmatic. Volcanoes near plate boundaries and mid-ocean ridges are built by decompression melting of rock in the upper mantle. The lower density magma rises through the crust to the surface.  Seamounts are typically formed from extinct volcanoes that rise abruptly and are usually found rising from the seafloor to in height
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Seamount [SEP] Grouping
Otherwise, seamounts tend not to form distinctive chains in the Indian and Southern Oceans, but rather their distribution appears to be more or less random. Isolated seamounts and those without clear volcanic origins are less common; examples include Bollons Seamount, Eratosthenes Seamount, Axial Seamount and Gorringe Ridge.