Late Mesozoic-Cenozoic Evolution of the Conjugate Lofoten-VesteråLen (Nordland Vi-Vii) and NE Greenland Continental Margins: Implications for the Potentially Developed Petroleum System

Filippos Tsikalas¹, Jan Inge Faleide², Olav A. Blaich², Asbjørn J. Breivik², Rolf Mjelde³, and Olav Eldholm^3
1Exploration Department, Eni Norge AS, Stavanger, Norway.
²Department of Geosciences, University of Oslo, Oslo, Norway.
³Department of Earth Science, University of Bergen, Bergen, Norway.

Late Mesozoic-Cenozoic tectono-stratigraphic correlations between the conjugate Lofoten-Vesterålen and NE Greenland continental margins are provided based on a refined structural and stratigraphic framework off mid-Norway, early opening plate reconstructions, and a regional grid of MCS profiles off NE Greenland. Constraints on the conjugate crustal structure, magmatism and breakup derive from analysis of a new OBS survey and compilation of earlier wide-angle seismic velocity profiles, as well as from crustal-scale 2D gravity modeling. A series of conjugate regional transects have been constructed and reveal important vertical and lateral variations in crustal architecture as well as basin configuration and stratigraphy resulting from a complex history of rifting prior to and during the last rift episode in Late Cretaceous-Early Cenozoic time, leading to breakup and volcanic passive margin formation. Locally thick Upper Paleozoic-lower Mesozoic sequences are recognized (dominantly offshore NE Greenland) that together with interpreted Middle-Upper Jurassic-lowermost Cretaceous sequences define petroleum system play models similar to the well-established ones offshore mid-Norway (e.g. Halten and Dønna terraces) and Barents Sea. Although the composite late Middle Jurassic-earliest Cretaceous rifting is the dominant tectonic episode, we also observe structural and stratigraphic relations that indicate two additional rift phases with obvious petroleum play system implications: an Aptian-?Albian rift phase, probably coeval with similar events elsewhere on the NE Atlantic margins; and Late Cretaceous rifting, with onset in middle Campanian time, that is characterised by low-angle detachment faulting, culminating with regional uplift, intrusive igneous activity and subsequent erosion towards the end of the Paleocene. Thick seaward dipping reflector sequences manifest massive eruptions of lavas during breakup at the Paleocene-Eocene transition. The post-breakup passive margin development is characterised by the transport and deposition of large amounts of sediments in response to margin subsidence and continental uplift, particularly during two distinct phases of outbuilding in Oligocene?/Middle Miocene and Plio-Pleistocene times, which may have affected considerably the underlying petroleum system. Of special interest are a number of mid-Cenozoic intra-basin inversion features recognised both off Norway and off Greenland, revealing a regional compressive regime.

AAPG Search and Discover Article #90096©2009 AAPG 3-P Arctic Conference and Exhibition, Moscow, Russia