EDIACARAN FOSSILS FROM THE INNERELV MEMBER (LATE PROTEROZOIC) OF THE TANAFJORDEN AREA, NORTHEASTERN FINNMARK

An Ediacaran assemblage dominated by an unidentified species of Cyclomedusa Sprigg 1947, along with species of Ediacaria? Sprigg 1947, Beltanella Sprigg 1947, Hiemalora Fedonkin 1982, and Nimbia? Fedonkin 1980, is described for the first time from the Innerelv Member of the Stappogiedde Formation exposed in coastal outcrops west of Tanafjorden on Digermul Peninsula, in northeastern Finnmark, northern Norway. The fossil assemblage is dominated by discoidal forms which share certain affinities with the cosmopolitan genera. Cyclomedusa and Ediacaria. However, our specimens differ from these and other discoidal Ediacaran fossils in the absence of radial sculpture. This, along with a basically concentric organization, are characteristics shared with Kullingia from the Dividal Group of northern Scandinavia, the White Sea, Podolia. and northwestern Canada, along with undescribed discoidal remains from the Charnian Supergroup, Charnwood Forest, Leicestershire, England, and the Conception Group, Avalon Peninsula, Newfoundland. Our discovery of an Ediacaran-type assemblage within the Middle Innerelv Member provides support for previous suggestions of a late Vendian age for this sequence. This general conclusion is consistent with the occurrence of early Cambrian taxa, including the trace fossil Phycodes, and the problematical forms Vendotaenia and Sabellidites, in basal portions of the Lower Breivik Formation, within the same stratigraphic section. The lowest formally-proposed faunal zone in northern Scandinavia is the Kullingia Zone, based on the occurrence of the fossil medusoid Kullingia concentrica in Member III (Middle Sandstone C) of the Dividal Group, northern Scandinavia. Kullingia is a distinctly chambered form that was probably pelagic. In contrast, Cyclomedusa, and related genera of the so-called Cyclomedusa plexus, comprise an informal grouping of intergrading, probably benthic, taxa that possess radial and/or concentric organization. In light of the intergradational nature of taxa, present difficulties in taxonomic interpretation and correlation, and the abundance of cyclomedusoids in many Ediacaran assemblages, we suggest that the concept of the Kullingia Zone, as originally defined for northern Scandinavia, be broadened to include the common form genera of the Cyclomedusa plexus, inclusive of the occurrences in the Innerelv Member described herein. It is our hope that additional fieldwork will provide a basis for more refined taxonomic evaluations and biozonation.