Changes

==Buoyancy pressure profile==

==Buoyancy pressure profile==

[[file:predicting-reservoir-system-quality-and-performance_fig9-15.png|thumb|{{figure number|2}}From Coalson et al.<ref name=Coalsonetal_1994>Coalson, E. B., S. M. Goolsby, and M. H. Franklin, 1994, Subtle seals and fluid-flow barriers in carbonate rocks, ''in'' J. C. Dolson, M. L. Hendricks, and W. A. Wescott, eds., Unconformity related hydrocarbons in sedimentary sequences: Rocky Mountain Association of Geologists (RMAG) Guidebook for Petroleum Exploration and Exploitation in Clastic and Carbonate Sediments, p. 45-58.</ref> Courtesy RMAG.]]

[[file:predicting-reservoir-system-quality-and-performance_fig9-15.png|thumb|{{figure number|2}}Relationship between the hydrocarbon gradient and water gradient. From Coalson et al.<ref name=Coalsonetal_1994>Coalson, E. B., S. M. Goolsby, and M. H. Franklin, 1994, Subtle seals and fluid-flow barriers in carbonate rocks, ''in'' J. C. Dolson, M. L. Hendricks, and W. A. Wescott, eds., Unconformity related hydrocarbons in sedimentary sequences: Rocky Mountain Association of Geologists (RMAG) Guidebook for Petroleum Exploration and Exploitation in Clastic and Carbonate Sediments, p. 45-58.</ref> Courtesy RMAG.]]

When a reservoir has formed in a trap and has come to pressure equilibrium with the water in the aquifer, the pore pressure of the hydrocarbons at different depths in the reservoir plot along a steeper gradient than the water gradient. [[:file:predicting-reservoir-system-quality-and-performance_fig9-15.png|Figure 2]] shows this relationship.

When a reservoir has formed in a trap and has come to pressure equilibrium with the water in the aquifer, the pore pressure of the hydrocarbons at different depths in the reservoir plot along a steeper gradient than the water gradient. [[:file:predicting-reservoir-system-quality-and-performance_fig9-15.png|Figure 2]] shows this relationship.