Caledonian magmatic activity in south-eastern Greenland

Abstract

THE position of the Caledonian front in eastern Greenland is important1,2 in any reconstruction of the pre-drift North Atlantic (see ref. 3). No evidence of any Caledonian activity has yet been found south of Scoresby Sund, however, where the Caledonian Front, exposed in Gaseland4, is seen to pass under the thick plateau basalts of Kong Christian den IX's Land5. South of the basalts, only Precambrian ages have been obtained2. We report here on a complex of Caledonian age in the Kangerdlugssuaq district, which lies about 300 km to the south of the Gaseland exposures. Unknown Caledonian events may be recorded in basement rocks of the areas, and may be uncovered by more detailed investigation. Moreover, petrological similarities between the new complex and the alkaline suite found in Assynt, northwestern Scotland, may provide a further link in the North Atlantic jigsaw puzzle.