# Multi-Parametric Imaging of Etruscan Chamber Toms:
## 3 Results
### GPR Results  
The GPR profiles conducted in Vigna la Piazza were performed to discover and locate possible, not-yet excavated, archeological remains, and to provide a constraint for the CCR and ERT recovered resistivity anomalies.  
The rough site morphology and its status has impeded the acquisition of data onto 3-D grids, forcing us to perform only single lines.  
Figure 5: ERT resistivity section. Electrical resistivity tomography (ERT) recovered resistivity model. Root mean square (rms) 2.5% after six iterations.  
Figure 6a shows the b-b' radargram (GPR2 profile in Figure 3) that was recorded on top of the excavated burial site (Eb1). As expected, the anomaly (G4, x = 17 m), due to the presence of voids, is clearly visible in the radargram where both the roof and floor returned strong and continuous reflections (dashed white lines in Figure 6b). The Eb1 roof depth is 1.6 m below the surface and its floor at about 3.5 m, as observed using tape measures. The GPR-derived burial dimensions are 1.5 m wide and 2 m high. The absence of noticeable and diffuse wave scattering along the profile indicates that the host media has near-homogeneous dielectric characteristics.  
A group of disarticulated strong amplitude reflections (G5, x = 5 m) occurred at the same depth as G4, separated by approximately 10 m. The distribution and amplitude of reflections suggest the presence of a partially void burial chamber that was probably refilled by fine-grained material. The latter is probably formed by weathered tuff, which has a very low dielectric contrast compared to the solid tuff. This particular configuration makes it impossible to correctly reconstruct the chamber geometry while allowing us to identify and locate it through the strong reflections from the void parts.  
The c-c' line (Figure 6b) was recorded on the flat area above the paved road and partially covered the first 20 m of the CCR2 profile (Figure 3). Here, the results were difficult to interpret due to the presence of more diffuse wave scattering occurring at a depth of approximately 1.5 m. At only one point (G7, x = 13 m), we observed an alignment of reflections stronger than the scatter average, with values similar to those recorded for the inferred voids aforementioned. Two additional spots, at x = 3 m and x = 19 m, showed similar reflections but were clearly disarticulated, thus making any interpretative hypothesis speculative.  
The a-a' line (Figure 6c) was recorded in the northern part of the study area along a small northwest-southeast oriented trail overlaying the CCR1 profile (GPR1 in Figure 3). According to the description and interpretation of the G4 anomaly, three evenly spaced and partially filled chambers were clearly recognizable at x = 6, 13, and 19 m along the profile. The G1 and G2 anomalies seem to be connected to the surface via small near-vertical holes visible at x = 5, 11, and 16 m.  
Figure 6: GPR radargrams. GPR radargrams obtained in the Vigna la Piazza Necropolis along (**a**) line b-b’ (GPR2 profile partially coincident with CCR2 line in Figure 3), (**b**) line c-c’ (GPR3 profile partially coincident with CCR2 line in Figure 3), and (**c**) line a-a’ (GPR1 profile partially coincident with CCR1 line in Figure 3). The dashed white lines mark the GPR anomalies associated with the presence of excavated (Eb1) and partially filled burials. Recovered GPR anomalies are labeled with capital letters from G1 to G7.  
Note that close to G3, a 7 m long, strong linear-shaped anomaly occurred starting at a depth of 1.7 m, becoming shallower to approximately 1.2 m below the surface. This anomaly was interpreted to be a small chamber or tunnel that is directly connected to G3 and elongated in the profile direction. The change in depth could be attributed to the change in the profile direction as a result of the trail path.