Changes

  | isbn    = 0-89181-602-X

  | isbn    = 0-89181-602-X

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Hydrocarbon column heights may not be related only to the displacement pressure of the top seal. Once a seal has been breached and hydrocarbons forced through the seal, theoretically the hydrocarbon column will shrink until the buoyant pressure equals the displacement pressure and the system again seals. In practice, however, hydrocarbons continue to flow through the seal until there is no longer a continuous hydrocarbon filament. Although the process is not completely understood, laboratory studies suggest that flow continues until the hydrocarbon column shrinks to half its original height.<ref name=ch10r65>Roof, J., G., 1970, Snap-off of oil droplets in water-wet pores: SPE Journal, vol. 10, no. 1, p. 85–90.</ref><ref name=ch10r67>Schowalter, T., T., 1979, Mechanics of secondary hydrocarbon [[migration]] and entrapment: AAPG Bulletin, vol. 63, no. 5, p. 723–760.</ref>

Hydrocarbon column heights may not be related only to the displacement pressure of the top seal. Once a seal has been breached and hydrocarbons forced through the seal, theoretically the hydrocarbon column will shrink until the buoyant pressure equals the displacement pressure and the system again seals. In practice, however, hydrocarbons continue to flow through the seal until there is no longer a continuous hydrocarbon filament. Although the process is not completely understood, laboratory studies suggest that flow continues until the hydrocarbon column shrinks to half its original height.<ref name=ch10r65>Roof, J., G., 1970, Snap-off of oil droplets in water-wet pores: SPE Journal, vol. 10, no. 1, p. 85–90.</ref><ref name=ch10r67>Schowalter, T., T., 1979, [http://archives.datapages.com/data/bulletns/1977-79/data/pg/0063/0005/0700/0723.htm Mechanics of secondary hydrocarbon migration and entrapment]: AAPG Bulletin, vol. 63, no. 5, p. 723–760.</ref>

==Most traps half full==

==Most traps half full==