The terrane concept and the Scandinavian Caledonides

Abstract

A revised terrane map is presented for the Scandinavian Caledonides, and an outline is given of the principal suspect and exotic terrane-complexes identified outboard from the Baltoscandian miogeocline. The outermost part of the Baltoscandian continental margin is itself suspect, in the terrane sense, since the true palaeogeographical locations of rocks now represented in the Seve and Sørøy-Seiland Nappes, while inferred, are not known. The orogen-internal exotic terranes embrace the oceanic\/eugeoclinal elements of the Caledonides, represented by the magmatosedimentary assemblages of the Køli Nappes, including ophiolite fragments and island arc products. Even more exotic terranes occur in the highest parts of the tectonostratigraphy, including units which are thought possibly to derive from the Laurentian side of lapetus.