Integrated archaeological and geophysical studies at the Ust-Tartasskie kurgany site: new methods and techniques

This article compares archaeological and geophysical data from archaeological works at burial mound No. 51 of the Ust-Tartasskie Kurgany site (south of Western Siberia). Prior to excavation, it was explored using a number of remote methods, including ground-based magnetic survey, aerial photography, electromagnetic profiling, and electrical tomography. The magnetic survey employed vertical and horizontal gradient methods. Comparison of results has revealed a good correlation of data. Structural assessment of the burial site according to magnetic data was significantly complicated by anomalies associated with presence of iron objects in the soil, ruts of field roads, and traces of plowing. According to magnetic surveys, burial mound consisted of the central burial object surrounded by a moat. During the excavation, 22 burials have been discovered, nine of which were secondary. Comparison of archaeological and geophysical data has revealed that only the location of the moat could be established from magnetometric data, most likely because of the humus layer of the mound reaching 1.5 m in height. In such cases, it creates a kind of “screen” which hampers remote recognition of the mound structure. The anomaly which was identified as the central burial is most likely associated with ritual structure above the central burial, which burned for a long time during ritual activities.The digital elevation model which was built using aerial photography, clearly showed the mound, which confirms high efficiency of this method at low cost. Electromagnetic profiling and aerial photography have made it possible to detect and locate the mound. Comparison with data of electrical tomography has shown that results of electromagnetic profiling well correlated with the resistance layer at a depth of about 0.5 m. Apparently, high values of electrical resistivity in the area under study and their insufficient contrast did not make it possible to identify the burials in the mound. The best results were obtained from 3D inversion of electrotomography data, performed with a step of 0.5 m between the electrodes and 1 m between the profiles. Comparison of the data indicates that such detailed survey makes it possible to identify individual burials, and evaluate their parameters and differences in filling. The study confirms the effectiveness of our set of remote methods and establishes the parameters of the measuring setup, which should be used in studying similar objects in the future.