Field work in the Ivisârtoq area, inner Godthåbsfjord, southern West Greenland

Abstract

The field work reported on here is part of the 1:500 000 scale mapping programme of the Godthåbsfjord region (Allaart et al., this report). Ivisârtoq lies some 110 km north-east of Godthåb (50° 00'W, 64° 45'N, map 64 V 2 Kapisigdlit), (fig. 15). The area belongs to the central Archaean block of West Greenland (Pulvertaft, 1968) which in the Godthåbsfjord region has been shown to contain gneisses and associated amphibolites which may be broadly divided into two complexes (McGregor, 1973). The Amitsoq gneisses and included amphibolites have ages of c. 3700 m.y. (Black et al., 1971; Moorbath et al., 1972), and the Nûk gneisses and associated amphibolites and anorthosites ofc. 3000 m.y. (Pankhurst et al., 1973; Moorbath & Pankhurst, 1976).