Search results for "Electrical tomography"
showing 5 items of 5 documents
Integrated geophysical survey in the archaeological site of Himera (Northern Sicily)
2005
An integrated program of geophysical survey, coring, and test excavations to study a 4th millennium bc-cal ditch at Alt del Punxó (Muro de L’alcoi, A…
2008
The potentially long and interesting archaeological sequence revealed by systematic survey at the site of Alt Del Punxó (Muro de l’Alcoi, Alacant) was the basis for initiating a study of the locality’s subsurface structures using new methods of remote sensing. Geophysical survey (magnetometry and tomography) and systematic augering revealed buried structures, including monumental earthworks, and guided subsequent excavations to collect more detailed data about the nature and age of these prehistoric features. The information recovered, including new radiocarbon dates, offers a new perspective on the organization of prehistoric populations in this region of south-central Valencia since the b…
Influence of different array datasets on reliability of electrical resistivity tomography
2015
The goal of this work is to study how the reliability of inverse model depends on a few basic parameters, as the combination of potential spacing and dipolar distance and, consequently, the number of measurements and of current dipoles, considering also how error affects inversion. The number of current dipole used is crucial, when using multichannel resistivity-meters, because it determines the overall acquisition time. A systematic comparison is presented between four 2D resistivity models and their images, obtained by the inversion of synthetic datasets relating to four different arrays: dipole-dipole (DD), pole-dipole (PD), Wenner-Schlumberger (WS) and multiple gradient (MG). For DD, PD…
Human settlement dynamics and alluvial dynamics of the Rhine River during the Holocene: Geoarchaeology of the site of Oedenburg (Haut-Rhin, France).
2007
The relationship between alluvial dynamics and control parameters such as climate are well known and understood at plurimillennial and pluriannual time-scales. But it is not really the case at multicentennial and multidecennal time-scales compatible with human society settlement time-scales. In a present and near future context, when human settlement may be affected by strong climatic variation, alluvial dynamics understanding is however a major centre of attention to the development of efficient models. To approach this scale-related question, a segment of the Upper Rhine River presenting both anastomosed and braided was investigated. This area also gives us the opportunity to study settle…
Approaching electrical tomography
2009
A general approach to electrical tomography is here described, based on the distribution of the experimental data to the set of voxels in which the subsoil has been divided. This approach utilizes the sensitivity coefficients as factors of the convolution procedure to execute the back projection of the data, to obtain the 3D pictures of the subsoil. A subsequent probabilistic filtering technique is described to improve the pictures in view of sharp boundary models. Some models are finally presented, mostly regarding cubic buried anomalies as well as pipe-shaped and L-shaped anomalies.