Abstract:
The results of joint fieldwork with geologists from the Geological Survey of Norway refine the Upper Proterozoic correlation scheme for the Barents Sea region and substantiate recognition of three structural-facial zones: Terskii (a continental area), Tana-Kil'din (a stable continental margin), and Barents Sea-Rybachii (an active transitional area to a continental slope). There were three extensive stages of the Late Proterozoic sedimentation: (1) the Late Riphean accumulation of undifferentiated deposits at the edge of an active continental slope (the Kongsfjord Formation, the Eina and Bargoutnyi groups); (2) deposition of transgressive differentiated sediments, including carbonates, in the terminal Late Riphean (the uppermost beds of the Barents Sea Group, the Vadso and Tana groups, Kil'din Group, and a part of the Volokovaya Group); and (3) the Late Riphean-Vendian sedimentation marked by accumulation of tillite horizons in the Norwegian territory (the Lokvikfjellet and Vestertana groups and, probably, a part of the Volokovaya Group). The large lineament separating the Tana-Kil'din and Barents Sea-Rybachii zones is named "The Sokolov line" in honor of B.S. Sokolov, who was first to recognize this structural element as the northern border of the Russian platform in the Late Precambrian time.