Lower Cretaceous deep-water sandstone reservoirs of the UK Central North Sea

The Lower Cretaceous deep-water depositional system of the Central North Sea is emerging as a significant economic target. It contains a broad range of sedimentary facies and architecture. Thick sands were deposited by high-density sediment gravity flows. Unusual banded and mixed slurried facies represent the products of processes transitional between turbidity currents and debris flows. Shale-prone units show evidence of debris flows and post-depositional down-slope movement. Geometrical architectural elements include narrow linear incised channels, broad linear sand-rich fairways, prograding sand lobes and laterally extensive sheets. Models for exploration and production are refined by core magnetic measurements, automated quantitative petrography, detailed structural analyses and biostratigraphical zonations. Key remaining challenges are refining depositional models to aid prediction of lateral facies variations, understanding trap mechanisms and geometry and improving images of sandstone units on seismic data.