Changes

{{publication  

{{publication  

  | image  = exploring-for-oil-and-gas-traps.png

  | image  = exploring-for-oil-and-gas-traps.png

  | part    = Predicting the occurrence of oil and gas traps

  | part    = Predicting the occurrence of oil and gas traps

  | chapter = Evaluating top and fault seal

  | chapter = Evaluating top and fault seal

  | frompg  = 10-1

  | frompg  = 10-77

  | topg    = 10-94

  | topg    = 10-78

  | author  = Grant M. Skerlec

  | author  = Grant M. Skerlec

  | link    = http://archives.datapages.com/data/specpubs/beaumont/ch10/ch10.htm

  | link    = http://archives.datapages.com/data/specpubs/beaumont/ch10/ch10.htm

Seal capacity is controlled by the physical properties of both the [[seal]] and the [[hydrocarbon]]. Because the seal alone does not control seal capacity…

Seal capacity is controlled by the physical properties of both the [[seal]] and the [[hydrocarbon]]. Because the seal alone does not control seal capacity…

* It is possible to trap more [ http://www.glossary.oilfield.slb.com/en/Terms/n/natural_gas.aspx gas] than oil despite the higher [[Buoyancy pressure|buoyant pressure]] of gas,

* It is possible to trap more [http://www.glossary.oilfield.slb.com/en/Terms/n/natural_gas.aspx gas] than oil despite the higher [[Buoyancy pressure|buoyant pressure]] of gas,

* At depths below 9,000–10,000 ft a seal is always capable of trapping more gas than oil, and

* At depths below 9,000–10,000 ft a seal is always capable of trapping more gas than oil, and

* The dominance of gas in the deeper parts of basins may reflect seal capacity as well as [[maturation]].

* The dominance of gas in the deeper parts of basins may reflect seal capacity as well as [[maturation]].

==Changes with depth==

==Changes with depth==

[[http://wiki.aapg.org/Reservoir_quality#Compaction|Compaction]] and [[diagenesis]] during burial cause a progressive reduction in pore throats in most seal lithologies. In addition, the interfacial tension of the hydrocarbons changes with depth and affects seal capacity. Most importantly, the interfacial tension of oil and gas changes at different rates.<ref name=ch10r92>Watts, N., L., 1987, Theoretical aspects of cap-rock and fault seals for single and two-phase hydrocarbon columns: Marine and Petroleum Geology, vol. 4, no. 4, p. 274–307., 10., 1016/0264-8172(87)90008-0</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>

[[Reservoir_quality#Compaction|Compaction]] and [[diagenesis]] during burial cause a progressive reduction in pore throats in most seal lithologies. In addition, the interfacial tension of the hydrocarbons changes with depth and affects seal capacity. Most importantly, the interfacial tension of oil and gas changes at different rates.<ref name=ch10r92>Watts, N., L., 1987, Theoretical aspects of cap-rock and fault seals for single and two-phase hydrocarbon columns: Marine and Petroleum Geology, vol. 4, no. 4, p. 274–307., 10., 1016/0264-8172(87)90008-0</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>

==Seal capacity for oil and gas==

==Seal capacity for oil and gas==

[[Category:Predicting the occurrence of oil and gas traps]]  

[[Category:Predicting the occurrence of oil and gas traps]]  

[[Category:Evaluating top and fault seal]]

[[Category:Evaluating top and fault seal]]