Time-domain IP and Resistivity Sections Measured at Four Landfills with Different Contents

Four IP and resistivity sections measured in four landfills with different contents but in comparable geological settings are compared. The normalized chargeability makes it possible to distinguish waste from natural geological materials and to solve ambiguities remaining when the sole direct-current resistivity is used. The amplitude on the IP response is more important on the two landfills containing large amounts of biodegradable organic matter and disseminated metals. It is weaker when these materials are absent. It also appears larger when the moisture content is high. Some uncertainties remain concerning the depth of investigation but high normalized chargeability seems to extend to possibly contaminated sediments below the landfills.