Precambrian rocks of the Angmagssalik area, East Greenland

Abstract

The area between Angmagssalik fjord (ca. 66°N) and Køge Bugt (65°N) shown in fig. 3 was mapped by the writers during a two month field season in the summer of 1967. The Precambrian rocks of the area consist dominantly of biotite-hornblende or biotite-chlodte-epidote feldspathic gneisses (the grey gneisses of Wager, 1934). In these are intercalated pelitic, semipelitic and calcareous migmatitic gneisses with amphibolite facies mineral assemblages. The gneisses contain large numbers of concordant, semi-concordant and discordant bodies of metamorphosed basic and ultrabasic igneous rocks. Some of these are found interlayered with the metasediments.