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  | isbn    = 0-89181-602-X

  | isbn    = 0-89181-602-X

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Water saturation 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 crossplot.<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> This article 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 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 crossplot.<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==