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

The Lower Cretaceous deep-water depositional system of the Central North Se a is emerging as a significant economic target. It contains a broad range o f sedimentary facies and architecture. Thick sands were deposited by high-d ensity sediment gravity flows. Unusual banded and mixed slurried facies rep resent the products of processes transitional between turbidity currents an d debris flows. Shale-prone units show evidence of debris flows and post-de positional 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 prod uction are refined by core magnetic measurements, automated quantitative pe trography, detailed structural analyses and biostratigraphical zonations. K ey remaining challenges are refining depositional models to aid prediction of lateral facies variations, understanding trap mechanisms and geometry an d improving images of sandstone units on seismic data.