الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The joint application of electric and magnetic techniques for archaeological prospecting represents a very useful tool for imaging the near surface conditions and can provide a quantitative contribution to describe the spatial distribution of buried objects. In the present study, an integrated geophysical survey programme using magnetic and Direct Current (DC) resistivity techniques was considered at Tell Dibgou in the northern part of El-Sharkia Governorate. The objectives of the geophysical survey were to test which geophysical technique is most appropriate to image the buried targets through a comparison with information from excavation activities which were carried outduring and after the geophysical surveys.
According to the field observations, DC resistivity (2D and 3D) and magnetic measurements(total and vertical gradient) were carried out in this study through gradual steps in order to:(1)study the effectiveness, limitations and potential benefits of usingsuch near-surface, non-invasive geophysical techniques, and (2) integrate their findings so as to achieve an understanding of the geophysical response of data sets of different origin.
In the present investigation,five represented sites within Tell Dibgou were selected for executing geophysical survey depending on(i) diversification of chronological periods, (ii)suitable soil conditions for geophysical surveys and (iii) surface inspection and the available excavations. The DC resistivity survey, in form of 2D and 3D, was carried out to imagethearchaeological features and cultural relicsin the high lands of the area. Eleven 2D resistivity profiles were carried out using different electrode configurations. For 3D resistivity survey, pole-pole array was applied to acquire the data over inferred buried room from previously 2D and magnetic surveys. The measured resistivity datawas processed and inverted using both the default (conventional) smoothness-constrained and blocky (robust) inversion. In general, the applied robust inversion showedsharper and straighter boundaries than the conventional technique.The 3D resistivity model and 2D inverted sections revealed relatively high resistivity zones at depths ranging from approximately 0.5 to 3 m. In comparison with the available archaeological evidence, these higher resistivity zones are the most promising locations for archaeological excavation.
Simple techniques were applied to the magnetic data to remove the artifacts of non-archaeological origin such as chevron, spiking, stripping, edge mismatch, and first order trends or slopes across the map. The magnetic anomalies were isolated and enhanced using numerous techniqueswhich include wavelength filtering, vertical and horizontal derivatives and continuation filtering (upward and downward) which might help in the resolution and better definition of the anomalies.
In this work, an attempt was made to study the depth estimation and source-edge detection using 3D Euler Deconvolution (ED) and Tilt Angle Derivative (TAD) techniques of total and vertical magnetic gradient data. The depthscomputed by ED are in good agreement with those obtained from the TAD. The baked brick walls of ancient structures which were demarcated by both geological field work and excavations were superimposed on the TAD and ED images.
The results of the magnetic survey, however, suggested that almost the whole of the archaeological site contains significant archaeological anomalies. Interpretation of magnetic maps show some linear anomalies, which may represent fired brick walls of ancient Islamic rooms, as well as some closed anomalies, which refer to small food kilns belongs to Third Intermediate Period or water tank from fired brick of Byzantine archaeological Era. The depths to top of these buried structures were determined to help archaeologists in their future excavation works.