Some minor and trace elements in Archaean marbles and metamorphosed silico-carbonatites from the Fiskenæsset region

In 1970, A. M. Hopgood found rare concordant marble layers within the gneisses near Frederikshåbs Isblink. At that time, there was considerable discussion among the geologists participating in the mapping ofthe Fiskenæsset region on the origin ofthese gneisses. The finding of these marble layers indicated a sedimentary origin for at least some of the gneisses, provided that the marbles themselves were metasediments, and not, for example, meta-carbonatitic lavas. To answer this last question an investigation of some trace elements in these rocks was undertaken. Very fortunately Hopgood also found a few discordant carbonate-rich rocks in the same area so that a direct comparison between the two rock types could be made. The analyses reported in this paper were made by H. Bollingberg in the Spectrographic Laboratory of the Petrological Institute of Copenhagen University. The study was suggested and coordinated by F. Kalsbeek.