Die Anorthosite des Sulitelma—Salojauregebietes, Kaledoniden, Nordschweden

Abstract

Title: The Anorthosites of the Sulitelma-Salojaure Region, Caledonides, Northern Sweden. From the Big Seve nappe three occurrences of Meta Anorthosite are described. One, situated in the Pieske nappe, is younger than the Upper Ordovician Laotak series. Intrusive anorthosites in the Vasten nappe are younger than schists of Lower Ordovician age. In the Gasak nappe, anorthositic rocks occur as pebbles and boulders in polygeneous basal conglomerates of the Upper Ordovician Laotak series and as traces of the deeply weathered anorthositic basement of the nappe beneath the conglomerates. Here the anorthosites are older than the other occurrences of the region. They are of Pre- Upper Ordovician age. They may have been formed during the Ekne disturbance, which has been compared with the Taconic orogenesis in North America, but it is also possible that they belong to the Pre-Cambrian basement of the Gasak nappe. The several anorthosites described from a restricted area such as the Sulitelma-Salojaure Region show, that these rocks abundantly occurring in the western parts of the Caledonides, might be of different age.