TN366 : Application of geophysical methods Ground penetrating radar (GPR) and Electrical Resistivity Tomography (ERT) in archaeological investigations, a case study Tepe Hissar archaeological site
Thesis > Central Library of Shahrood University > Mining, Petroleum & Geophysics Engineering > MSc > 2011
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Abstarct: This research was aimed to combine the results of ERT and GPR methods to achieve a better view of subsurface and having a more accurate interpretation Finally investigating both methods capabilities and weak points in comparison to each other in archaeological investigation.
There were some assumptions concerning site conditions. Any buried structure is probably denser than its surrounding material. As a result it should be more resistive than the surrounding environment. This is the contrast that geoelectrical methods can detect. If the assumption comes true the decay rate of GPR waves in surrounding materials will be faster than the buried structure, therefor in GPR sections they will be visible in the form of areas with lower depth of penetration. If an empty space (grave or furnace) exists in subsurface, its resistivity will be much higher than its surrounding, and its electromagnetic contrast will be enough to be detected by GPR. In both cases (existing a buried structure or an empty space) there would be enough physical contrast between the archaeological targets and their surrounding environment for both geophysical methods.
The acquisition grid was designed, then data were collected and appropriate processes were applied on the data. The results of both methods were in good agreement and indicated the presence of anomalies in the south-west of the study area surrounded by fine particle textured clay. Concerning the shape and the size of the detected anomalies, they probably related to the remaining section of buried walls. The buried walls in ERT method are seen by high resistivity areas and the surroundings can be seen as low resistivity parts. In GPR sections the walls can be distinguished from the surrounding environment with higher depth of penetration. GPR is much faster than ERT; however the GPR waves have been rapidly attenuated because of high conductivity of the study area. In this study ERT could detect greater depths and had better resolution than GPR.
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