A detailed reconstruction of sediments deposited in the Norwegian Sea over the past 65 million years – the Cenozoic sequence – is being extensively used as a foundation for analysing geological plays and prospects.
A painstaking interpretation of the depositional and burial history of the entire Cenozoic succession between the 63rd and 68th parallels has been completed.
Identifying tectonic episodes and changes in basin physiography was particularly important, since these would have affected the generation and migration of hydrocarbons as well as the location and arrangement of potential sandstone reservoirs.
The almost total absence of Cenozoic sediments on the adjacent Norwegian mainland points to several phases of uplift and erosion.
Most of these dynamic changes occurred in response to seafloor spreading as Norway and Greenland started to pull apart during the Eocene about 50 millions years ago, a process which is still under way.
While this study provided considerable knowledge of the entire area, two specific features of regional significance emerged more clearly:
• the development of a widespread unconformity in response to a strong compressional event in the middle to late Miocene ¬– about five to 10 million years ago – which can be observed throughout the North Atlantic
• a complementary fall in sea level, which triggered the seaward progression of a major delta system along the eastern margin of the Norwegian Sea – the Molo Formation (well 6610/3-1).
Showing relationships between the main sedimentary units. Note that the units are projected onto the section for the purpose of illustration.
