The Yakutat Block is a terrane in the process of accreting to the North American continent along the south central coast of Alaska.
The Yakutat Block is bounded on its southwest side by an as yet undefined underwater geologic feature known as the Transition Zone.
Thus it appears to be a terrane in the process of accreting rather than a block already sutured on to the Pacific or North American plate.
The western part of the block subducts with the Pacific Plate at a very low angle, exhibiting buoyancy caused by its composition.
There is about 20 mm per year (0.79 in) of contraction between the Yakutat block and the Pacific plate, which is probably accommodated on an offshore structure.