A listric fault model for the formation of the dipping reflectors penetrated during the drilling of Hole 642E, ODP Leg 104

Abstract

One of the primary objectives of the leg was to examine the nature of the dipping reflectors which characterize the outer margin of the Plateau, near the continent/ocean transition. Reflectors stratigraphically above the base reflector K were interpreted by most investigators as a thick dipping series of lavas which were erupted before, or during, the initial stages of the formation of the Norwegian Sea. This interpretation was supported by the results from Site 642, where drilling penetrated a 310-m thick cover of Cenozoic hemipelagic sediments overlying a 760-m succession of upper series lavas above reflector K. In this short note we review the available evidence on the nature of the Voring Plateau lavas. We then briefly discuss critical features of comparable subaerial lava piles exposed on other continental margins in the North Atlantic and in Iceland. Finally, we comment on the nature of the continent/ocean transition and propose a model to explain the geometry of the pile. -from Authors