These volcanoes erupted through continental crust. The next youngest section of the hotspot track forms the New England Seamounts in the Atlantic Ocean. They were active between 100 and 80 million years ago. The Corner Seamounts, farther to the east, formed around 75 million years ago.

How are seamounts formed?

At mid-ocean ridges, plates are spreading apart and magma rises to fill the gaps. Near subduction zones, plates collide, forcing ocean crust down toward Earth's hot interior, where this crustal material melts, forming magma that rises buoyantly back to the surface and erupts to create volcanoes and seamounts.

Why are seamounts formed?

They are formed primarily by rapid undersea buildups of basalt, a dark, fine-grained rock that is the main component of the ocean's crust. Seamounts form by submarine volcanism. After repeated eruptions, the volcano builds upwards into shallower water.