Mid-Palaeozoic metamorphism and polyphase deformation of the Forland Complex, Svalbard

Abstract

Abstract The Forland Complex of Prins Karls Forland has been subjected to mid-Palaeozoic greenschist facies metamorphism and polyphase deformation. Metamorphism was initiated prior to D 1 deformation and gave rise to a parallelism of stratigraphic and metamorphic reaction surfaces. D 1 gave rise to imbricately thrust, southwest-directed fold nappes which have not noticeably disturbed the isograd surfaces. D 2 , interpreted as belonging to the mid-Cenozoic West Spitsbergen Orogeny (WSO) which was coaxial but not coplanar with D 1 , produced crenulation folds and pressure solution cleavages and some thrusting. D 3 structures are related to the formation of the Prins Karls Forland–Forlandsundet–Oscar II horst and graben system which is a late expression of the WSO. The rejuvenation of the Prins Karls Forland horst along NNW–SSE faults, the large scale E–W flexures and ENE–WSW faults in the Forland Complex and Tertiary graben deposits are assigned to D 3 .