St. Helena Seamount chain
Encyclopedia
The St. Helena Seamount chain, also known as the St. Helena Seamounts, is an underwater chain of seamount
s in the southern Atlantic Ocean
. The chain has been formed by the movement of the African Plate
over the Saint Helena hotspot.
Seamount
A seamount is a mountain rising from the ocean seafloor that does not reach to the water's surface , and thus is not an island. These are typically formed from extinct volcanoes, that rise abruptly and are usually found rising from a seafloor of depth. They are defined by oceanographers as...
s in the southern Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
. The chain has been formed by the movement of the African Plate
African Plate
The African Plate is a tectonic plate which includes the continent of Africa, as well as oceanic crust which lies between the continent and various surrounding ocean ridges.-Boundaries:...
over the Saint Helena hotspot.