Sunken Micro-Continents of the North Atlantic: Do the Sub-Basaltic Crust of the Faroe Islands and the Rockall Plateau Basement Represent One Single Micro-Continent?

Abstract

Seafloor extension and associated rifting in the North Atlantic Area, which started in Early Paleogene (from −62 Ma), resulted in a few micro-continents being isolated and submerged below sea levels. Published isotopic data for sunken offshore continental materials (basement) in the North Atlantic area are quite sparse, but a few do exist for the Rockall Plateau, or more precisely the Rockall Bank. Isotopic data for Early Paleogene basaltic materials, covering basement rocks of the Rockall Plateau, have hitherto only been publicised for the NW margin of the Hatton bank. The Early Paleogene basaltic archipelago of the Faroe Islands, on which some isotopic data do exist, rests on an ancient sunken continental crust of unknown geochemical and isotopic compositions. The objective of this contribution is to assess potential lead isotopic relationships between the Rockall Plateau and the Faroese sub-basaltic basement, based on the sparse available isotopic data existing for the former and using available isotopic data for slightly contaminated Faroese basaltic rocks. The results reached in this contribution point to a likely association between the Faroese sub-basaltic basement and the basement of the Rockall Bank and hence the Rockall Plateau and potentially also between Faroese basaltic rocks and contemporaneous counterparts from the Hatton Bank.