NEW GEODYNAMIC MODEL OF THE EVOLUTION OF THE NORTHERN NORWEGIAN-GREENLAND BASIN

Abstract

The northern Norwegian–Greenland Basin includes the Knipovich Ridge, the youngest segment of the North Atlantic spreading zone, and Molloy spreading center. These two structures separate the basin into two sharply asymmetric parts: the Boreal Basin and the Pomorskii perioceanic trough (buried under the sedimentary cover) (Fig. 1). The younger age of the active Knipovich Ridge as compared with the Mona Ridge is emphasized by its discordant (superimposed) position relative to linear magnetic anomalies in the oceanic basement. Short segments of these anomalies distinctly retain strikes inherent to lineaments in the Greenland and Lofoten basins that accompanied accretion of the oceanic crust in the axial spreading center of the Mona Ridge during the entire Cenozoic. The well-manifested asymmetry of basins (relative to the Knipovich Ridge spreading center), distinct discordance of the ridge with magnetic anomaly patterns, and confinement of earthquake epicenters to the ridge—all these and other features gave birth to continuous debates on the formation geodynamics of this segment of the Norwegian–Greenland Basin.