Correlation between porosity, conductivity and permeability of sedimentary rocks — a ballistic deposition model

We contruct a porous rock structure by ballistic deposition of grains of two different sizes. The conductivity (σ) of the rock with brine-filled pores is calculated using a simple parallel resistor model, taking the tortuosity of the pore channels into account. The results are used to calculate the permeability (K) from an equivalent channel model. Variation of σ and K with porosity are compared with geological field data. The agreement is quite satisfactory.