First Investigations of In Situ Electrical Properties of Limestone Blocks of Ancient Monuments

Abstract

In situ rapid electrostatic investigations on calcareous stones of monuments provide information that strongly correlates with the geological characteristics of the stone and proves to be efficient for provenance identification and successive restoration. With a portable device, it is now possible to scan several thousand blocks on a face of a monument in a few hours. The evolution of the religious building construction practices between the 13th and the 17th centuries is studied. From the petrophysics point of view, the results clearly indicate a marked linear correlation between electrical conductivity and dielectric permittivity. This fact, which agrees with Maxwell-Wagner polarization modelling, confirms the part played by the clay content in the electric properties of the dry carbonate rocks constituting the monument stones. A first test using X-ray scattering analysis shows the part played by the relative content of illite, which is correlated with a decrease of the resistivity.

Permittivity mapping in the VLF–LF range using a multi‐frequency EMI device: first tests in archaeological prospection

“…(2)Field measurements: in experiments conducted on dry calcareous stones of historical buildings (Souffaché et al . ) using an electrostatic multipole configuration at 31.25 kHz, a greater variability is noted in permittivity than in conductivity (the ratios of the interquartile to the median being 1.26 and 0.70, respectively). Again, a greater variability in permittivity was observed at the site of Qalat al Bahrain.…”

Laboratory study of the electrical properties of Lutetian limestones in the 100 Hz to 10 MHz frequency range

“…These latter play an important role in the response to the application of an electric field due to their high specific surface with ionic double layer (Stern and diffuse layers) surrounding the clay particles (Leroy and Revil, 2009). The in situ measurements on ancient monuments (Souffaché et al ., 2016) using a decimetric sized instrument showed over two different depth of investigation (approximately 10 cm and 20 cm) significant variations of both the real and imaginary components of the effective permittivity over the whole volume of masonry stones belonging to the facings. It is worth noting that in the older monuments, i.e.…”

“…In the perspective of civil engineering applications and for construction, sedimentary rocks deserve special attention because builders have to be able to evaluate the interest of their extraction in situ and then to monitor over time their alteration in place in constructions. Restorers and building archaeologists have to assess their present health (Rozenbaum et al ., 2007) and also intend to identify the choices that could have been those of the builders of ancient monuments (Souffaché et al ., 2016). Good knowledge of the physical properties of these natural sedimentary materials is essential to achieve correct interpretations of the geophysical or non‐destructive tests whatever investigation technique is used.…”

Interpretation the Influence of Hydrometeorological Variables on Soil Temperature Prediction Using the Potential of Deep Learning Model

“…The research established by environmental science practitioners demonstrated the effect of temperatures in soil freezes and thaw states [12], deciding the seed harvesting dates [13], and moreover it influences infiltration [14], soil water systems [15]. In the past current trends, extensive use of machine learning techniques has been helping the meteorological and environmental sciences to set up widely optimized harvest systems harnessing artificial intelligence (AI) [16], [17], [26], [18]- [25].…”