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 = Predicting reservoir system quality and performance

  | chapter = Predicting reservoir system quality and performance

  | frompg  = 9-1

  | frompg  = 9-45

  | topg    = 9-156

  | topg    = 9-45

  | author  = Dan J. Hartmann, Edward A. Beaumont

  | author  = Dan J. Hartmann, Edward A. Beaumont

  | link    = http://archives.datapages.com/data/specpubs/beaumont/ch09/ch09.htm

  | link    = http://archives.datapages.com/data/specpubs/beaumont/ch09/ch09.htm

  | isbn    = 0-89181-602-X

  | isbn    = 0-89181-602-X

}}

}}

Water saturation can be measured directly from a sealed core, which is an expensive method, or it can be calculated from the Archie equation, which is less expensive. S_w can also be estimated using a graphical representation of the Archie equation known as the Pickett crossplot. This subsection discusses how to calculate S_w using the Archie equation, how to determine values for variables of the Archie equation, and how to make a Pickett crossplot.

Water saturation (S_w) can be measured directly from a sealed core, which is an expensive method, or it can be calculated from the [[Archie equation]],<ref name=Archie_1942>Archie, G. E., 1942, The electrical resistivity log as an aid in determining some reservoir characteristics: Petroleum Transactions of AIME 146: 54–62.</ref> which is less expensive. S_w can also be estimated using a graphical representation of the Archie equation known as the [[Pickett plot construction|Pickett plot]].<ref name=ch09r45>Pickett, G. R., 1973, Pattern recognition as a means of formation evaluation: The Log Analyst, vol. 14, no. 4, p. 3–11.</ref>

==See also==

==See also==

* [[Calculating s_w from the Archie equation]]

* [[Archie equation]]

* [[Determining r_t]]

* [[Determining Rt]]

* [[Determining [[porosity]] from density–neutron logs]]

* [[Determining porosity from density-neutron logs]]

* [[Calculating r_w from SP logs]]

* [[Calculating Rw from SP logs]]

* [[Constructing a Pickett plot]]

* [[Pickett plot construction]]

 

==External links==

==External links==

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

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

[[Category:Predicting reservoir system quality and performance]]

[[Category:Predicting reservoir system quality and performance]]