New insights on East Finnmark Platform palynostratigraphy and paleogeography - A study of three shallow cores from a Mississippian succession in the Barents Sea, Norway

摘要

Palynomorph assemblages from cores from three shallow stratigraphic boreholes (7029/3-U-1; 7127/10-U-2; 7127/10-U-3) drilled on the East Finnmark Platform have enabled the recognition of four miospore assemblages and two sub-assemblages from the Billefjorden Group in this area, rectifying earlier biozonations. The assemblages are correlated to the Western European biozonation and are based mainly on taxa abundance and the first and last appearances of selected species. All assemblages are Visean to possibly early Serpukhovian in age. Correlations with other biozonations from areas of similar paleolatitude are suggested. Our results suggest that strata assigned to the Billefjorden Group in the offshore may be slightly older than previously assumed. Even so, the Billefjorden Group succession in the offshore is younger than that recognized in the onshore. A mixed signature between the flora from the Arctic region and areas further south in the Euramerican Supercontinent has been observed which may be indicative that the Finnmark Platform was located in a microfloristic transitional region. Generically, the climate in this region was humid and warm during the Visean time which is reflected in the significant amount of neutral, humid and moderately humid floral elements represented by the miospore assemblages. (C) 2016 Elsevier B.V. All rights reserved.