Detection of Underground Targets Based on the Aeromagnetic Data Using the Analytic Signal and Euler Deconvolution and 3D Inversion Methods

Investigating the possibility of underground structures detection is one of the complicated problems. In this paper, magnetic data have been used and both direct and inverse problems have been considered. In direct problem, with the assumption of the known size and position of the structure, magnetic response is modeled. Then, using the modeled signals, some points about the detectability of the structures are discussed. In inverse problem, position of the underground target is estimated based on the analytic signal and Euler deconvolution methods and 3D inversion of the magnetic data. Finally, both of the direct and inverse problems are implemented based on the simulated data and some suggestions are made to decrease the probability of detectability of the underground targets. The results show a concealed military structure with a susceptibility more than 0.05 SI and the depth of less than 200 m can be detected and located in a nonmagnetic host rocks using aeromagnetic survey with a resolution more than 60 m between lines. With increasing the magnetic susceptibility of structure, the possibility of detection will be increased; so that if the susceptibility exceeds 0.01 SI, the possibility of detection will be increased to depth of 400 m.