THE ALEUTIANS ARC
A study of the 100 mile wide sea bed formed by a ripple of Magna as the Tectnoic Plates
of Pacific and North American first Converged during the making of Earth.
The Bering Sea floor is separate from the Pacific Ocean floor due
to the Kula Plate being rafted over the North America Plate.

The Kula Plate (meaning "all gone"); was entirely subducted under
the Pacific Plate  around 48 Million years Ago.

That was during the Cretaceous Period, when the Dinosaurs experienced success in Asiamerica.

The plate is today only a slab in the mantle under the Bering Sea.

The 2 diagrams below detail why VOLCANOs are located along the Northern Rim of the Arc.
The DASHED line in the white detail above, assumes the height of the Aleutian Arc before GLACIERS
ETCHED OUT the Islands that now exist on the Arc. Some Volcanoes punched up through the Islands.

A THIRD PLATE CAUSED A 100 MILE WIDE RIPPLE