Strike‐slip restoration of the Barents Sea Caledonides Terrane, Finnmark, north Norway

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Abstract
The Trollfjord‐Komagelv (T‐K) fault is a major WNW–ESE trending dextral strike‐slip fault which cuts the Caledonides of northern Norway, with a palaeomagnetically determined displacement of 500–1000 km. Although earlier interpretations suggested a pre‐Caledonian age for the strike‐slip displacement, our analysis shows that the fault movement was intimately associated with late Caledonian thrusting. The epizone/high‐intermediate baric type metamorphism of the Barents Sea Caledonides has been used to constrain their restored position relative to other units in the Caledonides in northern Scandinavia. This indicates a postmetamorphic dextral displacement along the T‐K fault of ∼415 km. The Kalak Nappe Complex straddles the line of the T‐K fault but has not been cut by it. Despite this relationship, it is argued that the Kalak Nappe Complex was emplaced prior to strike‐slip fault movement. North of the fault, structures reflect blind thrusting and passive roof duplex development, refolded by en echelon strike‐slip structures, indicating that T‐K fault movement started after thrusting. South of the fault, structures in the Gaissa Thrust Belt have been affected by strike‐slip movement, although final thrust movements deformed the T‐K fault. The Kalak Nappe Complex north of the T‐K fault was carried passively by the strike‐slip block while to the south, major thrusting occurred.