A method of evaluating an earth formation, the method comprising: estimating, using at least one processor, a complex permittivity from electromagnetic measurements made by an electromagnetic tool at a plurality of frequencies in a borehole penetrating the earth formation, wherein at least one frequency in the plurality of frequencies is at or near a high frequency limit of a real part of the complex permittivity for a particular polarization type of the earth formation; and estimating, using the at least one processor, a fluid saturation in the earth formation based on the estimated complex permittivity, wherein the step of estimating the fluid saturation comprises: using an imaginary part relative to a real part of each estimated complex permittivity to generate a spectral dielectric curve (810, 820); determining a distortion angle (830, 840) of the spectral dielectric curve (810, 820) at the high frequency limit, wherein the step of determining the distortion angle (830, 840) comprises estimating, at or near the high frequency limit, the rate of change of the imaginary part of the complex permittivity of the earth formation relative to the real part of the complex permittivity of the earth formation; and using the determined distortion angle (830, 840) of the spectral dielectric curve (810, 820) to estimate the fluid saturation in the earth formation. estimating, using at least one processor, a complex permittivity from electromagnetic measurements made by an electromagnetic tool at a plurality of frequencies in a borehole penetrating the earth formation, wherein at least one frequency in the plurality of frequencies is at or near a high frequency limit of a real part of the complex permittivity for a particular polarization type of the earth formation; and estimating, using the at least one processor, a fluid saturation in the earth formation based on the estimated complex permittivity, wherein the step of estimating the fluid saturation comprises: using an imaginary part relative to a real part of each estimated complex permittivity to generate a spectral dielectric curve (810, 820); determining a distortion angle (830, 840) of the spectral dielectric curve (810, 820) at the high frequency limit, wherein the step of determining the distortion angle (830, 840) comprises estimating, at or near the high frequency limit, the rate of change of the imaginary part of the complex permittivity of the earth formation relative to the real part of the complex permittivity of the earth formation; and using the determined distortion angle (830, 840) of the spectral dielectric curve (810, 820) to estimate the fluid saturation in the earth formation. using an imaginary part relative to a real part of each estimated complex permittivity to generate a spectral dielectric curve (810, 820); determining a distortion angle (830, 840) of the spectral dielectric curve (810, 820) at the high frequency limit, wherein the step of determining the distortion angle (830, 840) comprises estimating, at or near the high frequency limit, the rate of change of the imaginary part of the complex permittivity of the earth formation relative to the real part of the complex permittivity of the earth formation; and using the determined distortion angle (830, 840) of the spectral dielectric curve (810, 820) to estimate the fluid saturation in the earth formation.