|
Institute of Historical Geology and Palaeontology, University of Copenhagen, Øster Voldgade 10, Dk-1350 Copenhagen K, Denmark
Recent collections of Silurian graptolites from N Greenland have yielded much new information on the biostratigraphy of the area. The graptolites occur mainly in slope and trough sediments, some of which are now incorporated in the N Greenland foldbelt. The full sequence of graptolite zones established in Britain cannot be recognized. The oldest Silurian graptolites indicate a lower Llandovery atavus or cyphus Zone age and above this an intermittent succession of graptolite faunas are found throughout the Llandovery, Wenlock, Ludlow and into the Pridoli (transgrediens Zone only). There are differences between the zones recognized in the western and eastern parts of N Greenland. The spiralis Zone appears to be the most extensive, occurring all over N Greenland. The graptolite sequences in N Greenland correspond most closely with those reported from the nearby Canadian Arctic Archipelago, but are easily correlated with the graptolite faunas from the Cordillera region, especially from the northern part. Differences of faunal assemblages are tentatively correlated with changes in sedimentary environments, possibly indicating a difference in the spatial distribution of species in a living graptolite community.
