Processes:
The Hawaiian Islands were formed by volcanic activity.
Each island or submerged seamount in the chain is successively older toward the northwest. Near Hawaii, the age progression from island to island can be used to calculate the motion of the Pacific Oceanic plate toward the northwest
How they are formed:
As a crustal tectonic plates move over hot spots mantle material up wells and erupts on the surface of the plate to form a volcano, seamount or volcanic island.
Hope this helps:)