Tracking contaminant transport using time-lapse geophysics: A review on applications of electrical methods

Abstract

Time-lapse (4D) geophysics for monitoring subsurface processes comes as an emerging area of hydrogeophysics. The combined use of non-invasive or minimally invasive geophysical methods such as electrical resistivity, time-domain induced polarization, complex resistivity and self-potential, along with traditional approaches have become commonly used to image the near surface. The use of these geophysical methods is of increasing interest as these techniques provide spatial and temporal imaging of the subsurface processes that otherwise can only be measured at few specific spatial locations. This review discusses the studies carried out using 4D geophysics to monitor contaminant transport affecting subsurface water and hence potentially impacting water security of groundwater-dependent communities as well as ecosystems relying on shallow drainage from landfills. This article highlights a series of the recent case studies from different parts of the world, novel trends, and their potential applications to support water security in the Indian scenario.