The overburden pressure, hydrostatic pressure and normally compacted shale velocity are theoretical values or empirically derived from relevant well data, whereas the interval velocity is derived from seismic processing velocities using the Dix formula. Modelled input cubesParadigm's software was used for the manipulation of the various input cubes into the pressure prediction. A 3D overburden pressure vs. depth model was derived from a modelled porosity cube. This (shale) porosity cube was generated using a compaction curve below sea bottom (to allow for variable water depths), and was subsequently transformed into a density cube using a density-porosity relation empirically derived from well data. Integration of the density cube over depth resulted in the overburden pressure cube P ob . The hydrostatic pressure cube P hyd was made using an assumed hydrostatic gradient of 0.45 psi/ft and depth from MSL.The normal velocity cube V n was based on Wyllie's Time-Average equation for sonic rocks, which establishes a connection between transit time for the rock (∆T norm ) and transit time for the matrix (∆T matrix ) and fluid (∆T fluid ):

Discovered in 1966 and starting production in 1968, Leman was the second gas field to come into production in the UK sector of the North Sea. It is classified as a giant field with an estimated ultimate recovery of 11 500 BCF of gas in the aeolian dune sands of the Rotliegend Group. The field extends over five blocks and is being developed by two groups with Shell and Amoco being the operators. Despite being such an old field development drilling is still ongoing in the field with the less permeable northwest area currently being developed.

Discovered in 1966 and starting production in 1968, Leman was the second gas field to come into production in the UK sector of the North Sea and is still producing gas today. It is classified as a giant field with an estimated initial gas-in-place of 397 BCM of gas in the aeolian dune sands of the Rotliegend Group. The field extends over five blocks and is being developed by two licence groups with Shell and Amoco (now BP Amoco) being the operators