Integrated geophysical studies in the upper part of Sardis archaeological site, Turkey

Sardis is one of the most important archaeological sites of western Turkey, and the city covered with very thick soil layer. Thus, it is very difficult to predict the ruins from the surface. To determine the buried archaeological structures under the very thick soil, the integrated geophysical methods might effectively be useful. Thus, an integrated geophysical investigation, including magnetic, 2D resistivity, VLF-R and seismic methods, were carried out in the area. Magnetic data were collected using gradient measuring technique in the area that is about 2 ha. The data were processed with different signal and image processing techniques. Resistivity surveys have been applied using Wenner (only over the test profile) and pole–pole arrays in three investigation levels. Afterwards, the resistivity data were processed with 2D resistivity inversion, which includes two different solution techniques such as smoothness constrained and robust inversion. The VLF-R method has also been applied in limited area in which a very large anomaly zone was determined by magnetic and resistivity methods to test the responses of electromagnetic VLF-R data in archaeological sites. In addition, seismic tomography method was tested to observe the response of method for archaeological problems over the test profiles. Integrated geophysical methods indicated that the usage of many geophysical techniques linked with each other is very useful and efficient to determine the buried archaeological structures.