Reconnaissance work in the crystalline complexes of northern East Greenland between 72° and 74°N

Most crystalIine rocks of northern East Greenland have until recently been regarded as representing the deep-seated mobile core zone of the Caledonian orogenic belt (Haller, 1971). However, recent regional mapping and isotopic studies in the Scoresby Sund region indicate that the main development of the crystalline complexes relate to Archaean and Proterozoic orogenesis, with a relatively superficial Caledonian overprint (Henriksen & Higgins, 1976). It was a logical step to extend field studies northwards to the crystalIinerocks ofthe region between 72-74°N (fig. 32). These studies supplement isotopic work in progress on material from the crystaIline complexes collected by D. C. Rex (Leeds) in 1974 (Rex et· al., this report), as well as the research being carried out on various aspects ofthe Eleonore Bay Group by R. Caby (MontpeIIier) this report and H. Stendal (Copenhagen).