Investigations on ampbibolite facies orthogneisses, amphibolites and leucogabbros on Akugdlerssuaq, inner Godthåbsfjord

Abstract

Two weeks of June 1981 were spent examining the amphibolite facies orthogneisses, amphibolites and leucogabbros of Akugdlerssuaq, inner Godthåbsfjord (fig. 24). This area was visited by V. R. McGregor during the helicopter reconnaissance mapping programme of Godthåbsfjord in 1976 (Allaart et al., 1977). McGregor observed a sharp, concordant contact between a layered complex of amphibolite, leucogabbro and anorthosite and a unit ofbanded gneisses, considered to be predominantly Amítsoq. The area was revisited in 1981 for more detailed study of the relation between the orthogneisses and layered complex. Equal emphasis was placed on mapping at a scale of approximately 1:20000, detailed study of selected outcrops and sampling for geochemical and isotopic studies.