CIPA 2003 XIX 11 ' International Symposium, 30 September - 04 October, 2003, Antalya, Turkey 
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Compared to the two cases discussed above, linear or curved 
continuous signals are absent. The magnetograms seem to be 
characterized mainly by “spot” localized anomalies. For the 
correct interpretation of the signal the identification on field, 
during the data collection, of an almost outcropping grave was 
very helpful. Knowing its position in the surveyed area, it was 
possible to recognize its correspondent anomaly, named A in 
Figure 7a. This is a well-defined magnetic dipole normally 
oriented. Therefore the useful signal in the surveyed area is 
represented by dipolar anomalies whose maximum and 
minimum values vary respectively from +16 to +34 nT and 
from -10 nT to -5 nT. Some excavations were executed inside 
areas 1 and 2 of Figure 6. The limits of two trenches, for 
instance, are marked with a black line in Figures 7a and 7b 
while the tombs brought to the light are shown in the 
photographs of Figures 7c, 7d. The appropriate overlap of these 
photos with the relative magnetograms points out the good 
spatial correspondence and the likeness in shape between the 
magnetic archaeological sources and the detected anomalies. 
The tombs represent the magnetic sources as the filling material 
of clayey composition has a greater magnetic susceptibility then 
the surrounding grainstone. In the light of this archaeological 
feedback all the spot anomalies detected especially in the 
magnetograms 1 and 2 can be interpreted as buried graves and 
the necropolis seems to be spread out all over the area. 
In this study we also tried to make a synthetic model which 
could reproduce the observed signal. In particular the F anomaly 
whose sources have quite simple geometric features was 
chosen. They were approximated with two prismatic structures 
whose positions, dimensions and depth of burring were derived 
by measurements executed on field (Figure 8a). The only 
variable parameter was the intensity of magnetization; as the 
material filling the graves is predominately a clayey soil, a 
value of 0.26 A/m was assigned to it. Figure 8b shows the 
finally synthetic anomaly. The likeness with the experimental 
data is satisfactory in terms of dimension, location, shape and 
values. 
a) b) 
Figure 8. a) The black line shows on the magnetogram the 
layout of the prismatic structures used to approximate the 
sources of the F anomaly. 
3.4 Coppa Nevigata (Italy) 
.The settlement of Coppa Nevigata, located in the north of 
Apulia, offers a complete sequence of the Bronze Age and 
constitutes an important reference site for studying the recent 
prehistoric era of southern Italy. 
(http://antichita.let.uniromal.it/ricerca/ric_sect.htm). Since the 
beginning of the last century the La Sapienza University of 
Rome has been carrying on a systematic study on Coppa 
Nevigata. It is not known yet if the first settlements of the 
Bronze Age were fortified whereas the following phases after 
the XVII century B.C. are characterized by the presence of 
defensive boundary wall made of over 5 meter thick dry stones. 
Currently the excavations have recovered more than 70 meters 
of it. According to the framework of this kind of prehistoric 
settlement, archaeologists initially supposed that a defensive 
ditch strengthened with stone-made coverings should have 
existed and surrounded the inhabited area just outside the 
boundary walls. 
!800 MOO 1000 *0 2C0cm 
Figure 9. The five pseudosections arranged according to their 
relative position point out the curved trend of the detected 
anomalies and of their sources. 
In 2000 a d.c. electric survey was performed to verify this 
hypothesis. A detailed stratigraphic column of the ground 
resulting from a shallow drilling in a nearby area, suggested the 
presence of readable contrast of resistivity between the 
calcareous stones which the archaeological structures could be 
v made of and the surrounding material. The dipole-dipole 
pseudosection technique was considered the most appropriate 
method to detect the ditch. Five profiles, 18 m long were 
executed along parallel lines 5 m apart. Their locations, 
according to archaeologists’ suggestions, were chosen to 
intersect the probable lay-out of the ditch. 
The obtained pseudosections are visualized in Figure 9. The 
computed apparent resistivity varies in the range of [3, 77] 
Qxm. On the central-left part of the CpO pseudosection an area 
with two sloping high-resistivity anomalies enclosing a 
conductive one is well visible. This signal is still present in the 
other pseudosections but it tends to disappear gradually. This 
result may be explained by the fact that the buried sources 
connected to these anomalies follows the curve of the defence 
wall. An excavation close to the CpO pseudosection 
subsequently brought to the light a stone made artifact ( in 
correspondence to the first high resistivity value) characterized 
by a visible slope (Figure 10a). This artifact (XIV B.C.) was 
realized by an oblique cut made in the ground where a mixture 
of soils and stones was afterwards laid upon. Archaeologists 
also discovered (Figure 10b) another stone covering (the 
second high resistivity value) realized two centuries later and 
separated from the preceding one by a filling of earth (the 
embedded conductive feature).