Forward Modeling of the Internal Layers in Radio Echo Sounding Using Electrical and Density Measurements from Ice Cores

The measured density and conductivity of a 181 m ice core are used to calculate a profile of complex reflection coefficients. It is confirmed that the amplitude reflection coefficients due to the conductivity variations are negligible in comparison to the amplitude reflection coefficients due to the density variations. Using the magnitudes of these reflection coefficients we obtain a profile of the expected power being returned to the surface. The modeled power return is compared with the results of a short pulse electromagnetic reflection survey near the drill site. We also convolve the profile of complex reflection coefficients with a depth invariant input wavelet to produce a synthetic radargram for the top part of the ice sheet. The phase change given to wavelets reflecting from the conductivity variations has a negligible effect on the synthetic radargram. Using this simple model we are unable to match the positions of the internal layers in the synthetic radargram with those in the reflection survey.

Details