The Lower Cretaceous succession of the northwestern Barents Shelf: Onshore and offshore correlations

• Published in: Marine and Petroleum Geology
• Main Authors: Grundvåg, Sten-Andreas, Marin Restrepo, Dora Luz, Kairanov, Bereke, Sliwinska, Kasia, Nøhr-Hansen, Henrik, Jelbye, Mads, Escalona Varela, Alejandro, Olaussen, Snorre
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2017
• Subjects: VDP::Mathematics and natural science: 400::Geosciences: 450; VDP::Matematikk og Naturvitenskap: 400::Geofag: 450; Early cretaceous; Clinoforms; Barents sea geology; Dinoflagellate; biostratigraphy; Barents Sea; Carolinefjellet; Helvetiafjellet; Rurikfjellet; Svalbard; Arctic
• Online Access: https://hdl.handle.net/10037/14163; https://doi.org/10.1016/j.marpetgeo.2017.06.036

Accepted manuscript version. Published version available at https://doi.org/10.1016/j.marpetgeo.2017.06.036 . Licensed CC BY-NC-ND 4.0. The Lower Cretaceous succession in the Barents Sea is listed as a potential play model by the Norwegian Petroleum Directorate. Reservoirs may occur in deep to shallow marine clastic wedges located in proximity to palaeo-highs and along basin margins. In addition, shelf-prism-scale clinoforms with high amplitude anomalies in their top- and bottomsets have been reported from reflection seismic but they have never been drilled. In Svalbard, the exposed northwestern corner of the Barents Shelf, Lower Cretaceous strata of shelfal to paralic origin occur, and includes the Rurikfjellet (Valanginian–Hauterivian/lowermost Barremian), Helvetiafjellet (lower Barremian–lower Aptian) and Carolinefjellet formations (lower Aptian–middle Albian). By combining sedimentological outcrop studies and dinocyst analyses with offshore seismic and well ties, this study investigate the link between the onshore strata and the offshore clinoforms. Age-vise, only three (S1–S3) of the seismic sequences defined in the offshore areas correlate to the onshore strata; S1 correspond to the Rurikfjellet Formation, S2 to the Helvetiafjellet Formation and the lower Carolinefjellet Formation, and S3 to the upper Carolinefjellet Formation. Offshore, all three sequences contain generally southward prograding shelf-prism-scale clinoforms. A lower Barremian subaerial unconformity defines the base of the Helvetiafjellet Formation, and its extent indicates that most of the Svalbard platform was exposed and acted as a bypass zone in the early Barremian. Onshore palaeo-current directions is generally towards the SE, roughly consistent with the clinoform accretion-direction towards the S. The local occurrence of a 150 m thick succession of gravity flow deposits transitionally overlain by prodelta slope to delta front deposits in the Rurikfjellet Formation, may indicate that shelf-edges also developed in Svalbard. The late ...