Changes

==Seal capacity for oil and gas==

==Seal capacity for oil and gas==

[[file:evaluating-top-and-fault-seal_fig10-51.png|thumb|{{figure number|1}}After .<ref name=ch10r92 /> Copyright: Marine and Petroleum Geology.]]

[[file:evaluating-top-and-fault-seal_fig10-51.png|300px|thumb|{{figure number|1}}After .<ref name=ch10r92 /> Copyright: Marine and Petroleum Geology.]]

Because the interfacial tension of gas increases at a different rate from that of oil with depth, it is possible to trap more gas than oil. [[:file:evaluating-top-and-fault-seal_fig10-51.png|Figure 1]] shows the seal capacity (in feet) of a top seal for different hydrocarbon compositions with depth (after <ref name=ch10r92 />). Curves show the seal capacity for three different oils, ranging from 30–40° API and a GOR of 400–800. Methane has two different pressure gradients (0.7 and 0.45 psi/ft. The pore throat of the seal decreases with depth and compaction.

Because the interfacial tension of gas increases at a different rate from that of oil with depth, it is possible to trap more gas than oil. [[:file:evaluating-top-and-fault-seal_fig10-51.png|Figure 1]] shows the seal capacity (in feet) of a top seal for different hydrocarbon compositions with depth (after <ref name=ch10r92 />). Curves show the seal capacity for three different oils, ranging from 30–40° API and a GOR of 400–800. Methane has two different pressure gradients (0.7 and 0.45 psi/ft. The pore throat of the seal decreases with depth and compaction.