\epsilon_f = s_w \cdot \epsilon_w(T) + s_o \cdot \epsilon_o(T) + s_g \cdot \epsilon_g(T)

where

volumetric fractions of water, oil and gas phases: 

relative dielectric permittivity of water, oil and gas phases

fluid temperature


See also


Petroleum Industry /  Upstream / Subsurface E&P Disciplines / Fluid Analysis / Fluid Capacitance