The Insular Islands were an extended chain of volcanic islands forming an arc in what is now the Pacific Ocean during the Paleozoic and Mesozoic eras. The islands formed by subduction and melting of the Farallon Plate along a fragment (or microplate) upon which they rose called the Insular Plate.
The Insular Islands were a chain of volcanic islands that formed in the Pacific Ocean during specific geological periods. The process of their creation involved the subduction and partial melting of the Farallon Plate on a separate tectonic plate, which we now understand to be the Insular Plate.