| Summary: | Dielectric profiles of a series of ice cores taken along the Norwegian-U.S. IPY traverse of East Antarctica, from Troll Station to the South Pole. The ice cores were drilled up to 90 meters deep. A DEP device is used to measure dielectic permittivity and electric conductivity along the length of the cores.Values are measured at intervals of 5 mm, thus enabling a high-resolution determination of electrical properties. Electrical properties are largely influenced by the total salt content as well as the acidity of the ice. In high accumulation areas annual-layer counting is possible, but in low accumulation areas a chronology based on comparison of DEP records with each other is required. Volcanic layers in Antarctica are well documented and have been used to date ice cores. In addition, DEP data are necessary for the calibration of shallow radar data and the conversion of two-way signal travel time to depth. Thus, our DEP measurements will aid in the interpretation of GPR data as well as in dating the ice cores. Sufficiently dated ice cores and radar layers are crucial for the determination of accumulation rates.
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