Over the last two decades, 2D electrical resistivity tomography (ERT) surveys have been conducted to detect and map karstic features as the expected electrical resistivity contrast is high between sound limestone and weathering residue as well as between sound limestone and cavities filled with clayey or sandy sediments. However, karstic features often show complex 3D geometries which are not well reconstructed through 2D surveys. In this paper, the efficiency of 3D ERT in the identification of a fracture network located at the top of limestone bedrock is assessed through a field experiment. The results of the 3D ERT interpretations were confirmed by visual observations of an outcrop located 100 meters away. Moreover, former sinkholes which occurred near the investigated area are aligned following the directions pointed out with the 3D ERT survey. This indicates that local karstification probably affect fractures located at the surface of the bedrock leading to the formation of a cryptolapiaz.


Article metrics loading...

Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error