Rift and rifted margin deep-water depositional systems: Application to Late Jurassic – Early Cretaceous rifting on the NCS

The DeepRift project aims to generate new understanding of the deposits within deep-water continental rift basins and rifted continental margins with a focus on the Gulf of Corinth, Greece, and the Norwegian continental shelf. We will investigate how the structural evolution of rift sedimentary basins interacts with environmental change (e.g. climate and sea-level) to control the source(s), timing and routing of sediment into deep-water rift basins, and the location, geometry and heterogeneity of the resulting deep-water rift deposits. The project comprises four work packages that integrate analysis of new high-resolution seismic and bathymetry data, collected during the project, from the modern, deep-water depositional systems in an active rift (Gulf of Corinth), with new numerical modelling of sediment supply and deep-water sediment transport processes, and then applies these results to understand ancient, rift-related deep-water depositional systems on the Norwegian continental shelf. The project is led by the University of Bergen and involves academic partners in the UK, France, Greece and the USA, together with a group of Norwegian industry partners. The results of the project will directly address the lack of detailed knowledge of deep-water depositional systems in rift basins. It is at the forefront of tectonics and sedimentary research, and addresses identified knowledge needs of industry working on the Norwegian continental shelf. As part of the project we will train seven early career scientists in both observation and numerical modelling that integrates a wide range of disciplines involving structural and sedimentary geology, tectonics, and environmental change. Our research on the Gulf of Corinth will be fully integrated with the recent International Ocean Discovery Program (IODP) Expedition 381 in the Gulf of Corinth, and our research on the Norwegian continental shelf will be closely tied to industry working there.

Recent NCS hydrocarbon discoveries demonstrate significant value in Late Jurassic- Early Cretaceous syn-rift deep-water reservoir plays (e.g. Fenja, Nova, Syrah, King Lear). There is a great potential to add further value by improving the understanding of the key controls on the distribution and architectures of these deep-water channels and fans in the subsurface, where seismic resolution is limited, through improved identification and prediction of reservoir-trap-seal combinations. In this project aim to unlock this potential, by acquiring new bathymetry and seismic imagery of present-day, active deep-water channels and fans in the Gulf of Corinth to constrain channel and fan geometry, modelling the structural and environmental events that govern these geometries, and applying these lessons to parallel studies of seismic and well data from prioritised syn-rift deep-water areas on the NCS. Novel aspects of the plan are the acquisition of high resolution imagery of modern deep-water syn-rift, axial and transverse deep-water systems, and the use of core from recent IODP Expedition 381 to develop an unprecedented high-resolution chronologic framework within which sediment flux, sea-level and fault controls on these systems are quantified. Tectonic-surface process modelling will be calibrated by these studies of the modern Corinth rift to constrain the impacts of these controls upon sediment routing and turbidite depositional elements at a scale directly relevant to understanding subsurface reservoir quality. NCS subsurface case studies, selected in collaboration with partner companies, will develop workflows that incorporate data on the evolution of syn-rift normal fault networks, sediment source areas and sediment routing systems to best predict the distribution and geometry of their deep-water depositional systems within this source-to-sink context. This will lead to de-risking of reservoir presence, quality, architecture and stratigraphic trapping on the NCS.