Early Cretaceous Tectonostratigraphic Evolution of the Sogn Graben and Måløy Slope, northern North Sea (Agat Fm.)

The Lower Cretaceous Åsgard and Agat formations in the northern North Sea in the Sogn Graben – Måløy Slope, northern North Sea, represent a reservoir. The current understanding of the Lower Cretaceous succession is that its deposition occurred during the post-rift stage sourced by inherited topography generated during the syn-rift stage.

The Åsgard and Agat formations display variability, from shallow marine to deep marine. This study aims to improve the understanding of the distribution, the depositional setting, and the controlling factors on the lateral variabilities of the Åsgard and Agat formations in the Sogn Graben-Måløy Slope areas. This will be achieved by integrating 2D and 3D reflection seismic, combine with core descriptions and wireline-log data.

Preliminary observations show two different wedge levels in the vicinity of major faults: 1) Pre-Agat wedges and 2) intra-Agat wedges. These wedge levels indicate diachronous fault activity during the Early Cretaceous. Fault activity during the deposition of Agat Formation is supported by core data, where growth faults are observed. The reflection configuration of the Agat Formation is continuous with high to low amplitude. Additionally, the Agat Formation have a fine- to medium and occasional coarse grain-size. Massive sandstone with water-escape structures are interpreted as turbidites.