The region is underlain by the Coast Plutonic Complex, consist- ing of pre-to post-kinematic quartz diorite to granodiorite batho- liths intruded into Paleozoic to Mesozoic metasedimentary and meta- volcanic rocks. Younger supracrustal assemblages overlying deformed rocks include the (?)Cretaceous Gambier Group and Tertiary Bella Bella Formation volcanic rocks.

Metamorphism of the region in which the Swallop Creek kyanite occurrence is located is dominantly greenschist. However, in metasedimentary rocks adjacent to a foliated quartz diorite, kyanite has been recognized. Although garnet and sillimanite have been recognized in the same area, it is not known whether these minerals coexist with kyanite. If they do then the occurrence represents a small area of high grade metamorphic rocks within the mainly greenschist facies terrane.