Syn-tectonic emplacement of deep-marine reservoir sands at rifting margins: Including a case study from the Vøring Basin

This study focuses on the interplay between large-scale relay ramps and sedimentladen flows, specifically low-density turbidity currents that form one end-member of subaqueous sediment gravity flows. The main objective is to better understand the impact of syn-rift faulting on subaqueous sediment routes and to develop predictive depositional models at rifting margins. Much of the knowledge on sediment dispersal across fault zones comes from the continental realm, but in subaqueous settings only little is known about the effect of tectonic activity on the pathways of gravity flows. Footwall drainage in active rift settings is generally directed away from the basin, but a minority of sedimentary flows enters the basin across the border fault system. Relay ramps between en-echelon faults may thereby act as local entry points and sediment pathways for subaerial flows, providing access to large catchment areas and influencing sediment distribution. Their impact on sedimentladen subaqueous gravity flows, however, is barely studied. Understanding the effects of syn-sedimentary faulting on sediment dispersal is of paramount importance to better locate potential reservoir sands in rift sequences – the precursors of slope- and basin-floor fans in fully developed passive continental margins that are a major exploration target in many areas. In order to achieve the aim of this thesis a novel approach is developed, combining laboratory analogue experiments with numerical flow simulations. The results of this conceptual experimental study are compared to subsurface Palaeocene syn-rift data in the Vøring Basin offshore Norway, a frontier area in the exploration of turbidite systems, as well as with various field examples.GeotechnologyCivil Engineering and Geoscience