3D Quantitative Interpretation of Archaeo-magnetic Datasets

Recent advances in magnetic surveying have meant high-resolution data over archaeological sites can now be quickly obtained. However, post-survey processing still generally comprises a sequence of data correction and filtering prior to a 2D visual interpretation based on pattern recognition. Developments in the processing and modelling of aero-magnetic datasets have led to techniques that can identify the location and shape of anomalous sources, including providing depth information. This paper explores the possibility that several of these techniques can be adapted for use on archao-magnetic datasets. 3D models of subsurface magnetic susceptibility can be generated using inverse methods. Prior to inversion it is important that processing and filtering techniques do not alter the character of the measured signal. Inverse models suffer from the “inverse problem” where many models fit the data equally well. In order to help overcome this Euler deconvolution has be used to constrain the inversion routine, and provide confidence in the final result. Results from a case study over a Romano-Celtic temple, Silchester, UK are shown, and in order to test the robustness of the technique, the model has been compared to a GPR survey collected concurrently. Both models show equivalent features for each depth slice.