Underwater mountain ranges with oceanic crust forming a single mountain system

Underwater mountain ranges with oceanic crust forming a single mountain system with a length of more than 60 thousand km are called.

These underwater mountain ranges are called mid-ocean ridges. Their total length – about 60,000 km – indicates that the ridges are the largest relief form of the bottom of the World Ocean. Mid-ocean ridges are formed at the junction of lithospheric plates. That is why the bottom of the longitudinal fault formed by them (its depth reaches 3 km) is covered with volcanic rocks, and the slopes are covered with numerous volcanoes and geysers. Where the tops of the ridges come to the surface, islands are formed. Iceland, for example, belongs to the islands formed by the tops of the mid-ocean ridge.