CSAMT mapping of a deep hydrogeological structure in Mauritius Island

摘要

Controlled Source Audiomagnetotelluric (CSAMT) sounding were done at several locations along 5 profiles in south-western mauritius to map the resistivity and thickness of the upper layers of the volcanic sequence and to infer the aquifer system from the electrical interpretation. Several sounding were measured adjacent to wells to aid in correlating the geophysical interpretations to known lithologic logs. The sounding data were isotropic across the entire observational band width. One dimensional far-field modeling has been used to determine the resistivity stratification with depth. This study suggests that the main body of the aquifer is confined in a paleovalley containing young volcanic flows at depths ranging from 40 m to 180 m..