Channels, lobes and levees are inadequate architectural elements to describ
e sand body geometry in sand-rich deep-water systems. Sand sheets are the m
ost common architectural element. Elutriation modifies primary sedimentary
structures by mobilizing and reorganizing grains. This changes pore size di
stribution and permeability characteristics. Bed amalgamation and offset st
acking of sand sheets makes problematic the use of bed thickness in correla
tion. A down-scaling approach for reservoir modelling is recommended, as a
hierarchy of architectural elements that define up-scaling relationships ca
nnot be established.