A Pickett Plot is used to estimate which property?

A Pickett Plot is used to estimate which property?

• A. Cementation Factor
• B. Water Saturation
• C. Formation Water Resistivity
• D. Matrix Parameters for Sonic and Density Logs

Answer: (B)

A Pickett plot uses the relationship between porosity and resistivity to determine how much of the pore space is filled with water. It builds on Archie’s equation, which links formation resistivity to the water-filled portion of the rock: Rt = a Rw / (phi^m Sw^n). By plotting resistivity data against porosity on a log scale and comparing the measured point to curves that represent different water saturations (and typical cementation factors), you can read off the water saturation directly. This makes it a practical way to estimate Sw from conventional logs. It isn’t used to directly determine cementation factor, formation water resistivity, or matrix parameters for sonic and density logs; those inputs come from other sources or analyses, while the plot’s main purpose is to estimate water saturation.

A Pickett plot uses the relationship between porosity and resistivity to determine how much of the pore space is filled with water. It builds on Archie’s equation, which links formation resistivity to the water-filled portion of the rock: Rt = a Rw / (phi^m Sw^n). By plotting resistivity data against porosity on a log scale and comparing the measured point to curves that represent different water saturations (and typical cementation factors), you can read off the water saturation directly. This makes it a practical way to estimate Sw from conventional logs. It isn’t used to directly determine cementation factor, formation water resistivity, or matrix parameters for sonic and density logs; those inputs come from other sources or analyses, while the plot’s main purpose is to estimate water saturation.