Enhancing Electrical Contact with a Commercial Polymer for Electrical Resistivity Tomography on Archaeological Sites: A Case Study

Abstract

This communication reports an improvement of the quality of the electrical data obtained from the application of electrical resistivity tomography method on archaeological studies. The electrical contact between ground and electrode enhances significantly by using carbomer-based gel during the electrical resistivity tomography measurements. Not only does the gel promote the conservation of the building surface under investigation, but it also virtually eliminates the necessity of conventional spike electrodes, which in many archaeological studies are inadequate or not permitted. Results evidenced an enhancement in the quality of the electrical data obtained in the order of thousands of units compared with those without using the carbomer-based gel. The potential and capabilities of this affordable gel make it appropriate to be applied to other geoelectrical studies beyond archaeological investigations. Moreover, it might solve corrosion issues on conventional spike electrodes, and electrical multicore cables usually provoked for added saltwater attempting to improve the electrical contact.

Identifying Changes in Sediment Texture along an Ephemeral Gravel-Bed Stream Using Electrical Resistivity Tomography 2D and 3D

“…Electrical currents injected into the subsurface employ two electrodes, named current electrodes, which are commonly labelled as A and B. Simultaneously, potential measurements are addressed using another pair of electrodes, named potential electrodes, which are labelled as M and N [12,13]. The four-electrode-based measurement unit principle applies all along the electrical profile, resulting in an overlapping of layers, allowing for the generation of 2D electrical sections.…”

“…Additionally, ERT can be employed to map spatial variations of qualities within a mineral deposit in 3D [10,11]. Several authors conducted ERT surveys to study loose materials, assess mine tailings, and so forth [12][13][14][15].…”

Extended Tromograph Surveys for a Full Experimental Characterisation of the San Giorgio Cathedral in Ragusa (Italy)

“…Indeed, the importance of the analysis of the soil behaviour to the assessment of the whole built heritage system should not be neglected [ 3 ]. Nowadays, geophysical survey techniques are widely used as a strategic tool to characterise the soil and identify and investigate underground evidence, as for instance archaeological remains or even structural elements of the building [ 4 , 5 , 6 , 7 , 8 , 9 , 10 ]. The widespread use of these methods of investigation is linked to their non-invasive character, their aptitude to be applied to different contexts, especially in urban areas and, in some applications, and the possibility of exploiting the ambient noise originated by natural (e.g., micro tremors, marine waves, wind, meteorological conditions) or anthropic (e.g., human activities, traffic, industrial machinery) sources of vibration [ 11 ].…”

Improving the galvanic contact resistance for geoelectrical measurements in debris areas: A case study

“…Typically, this problem can be solved by adding salt water in the immediate vicinity of the electrodes (Binley, 2015) or by installing extra electrodes in parallel to the main ones (Hauck et al, 2008). Recently, during ERT measurements for archaeological surveys, a carbomer-based gel has been tested with success to improve the electrical contact between ground and electrodes (Vásconez-Maza et al, 2020). This commercial product, portable and easy-to-find, is a standard electrical enhancer for magnetic resonance imaging employed in medical diagnostic.…”