Electrical Resistivity Tomography Investigations of Multilayered Archaeological Settlements: Part II – A Case from Old Smyrna Höyük, Turkey

To determine the data acquisition and inversion capabilities of electrical resistivity tomography (ERT), which is used in multilayered archaeological settlements, an ERT survey was carried out at the Old Smyrna Hoyuk site, in the city of Izmir, Turkey. This site dates from the third millennium bc and ERT applications were performed using five different arrays (Wenner–alpha, Wenner–Schlumberger, dipole–dipole, pole–pole and pole–dipole). The resistivity distribution of the subsurface was investigated by two-dimensional and three-dimensional inversion routines, which use data obtained along orthogonal lines. To test the inversion treatments, ‘semi-fully three-dimensional’ and ‘quasi-three-dimensional’ approaches were also investigated, and comparison indicated a clear distinction between them. The results show that the quasi-three-dimensional solution had insufficient resolution, whereas the semi-fully three-dimensional data sets provide interpretable images of the subsurface. In addition, the effects of electrode array type and line interval and orientation were tested to define suitable ERT survey strategies for multilayered archaeological settlements. The array investigations show that dipole–dipole, pole–pole and pole–dipole arrays presented better quality images than the others. The line orientation tests performed in two perpendicular directions (N–S and E–W oriented lines) show that the N–S oriented lines are more suitable in terms of defining the buried architectural plan of Old Smyrna Hoyuk according to depth-slicing visualizations. However, the combination of the two perpendicular data sets could be useful if large between-line intervals are used. Finally, this ERT study clearly revealed the layered stratigraphy of Old Smyrna Hoyuk. Copyright © 2011 John Wiley & Sons, Ltd.