A Simplified Approach to Array Optimization for the DC Resistivity and Induced Polarization Method
S. Rejkjær, D. Belfrage, T. Dahlin and P. Tsourlos
Event name: 24th European Meeting of Environmental and Engineering Geophysics
Session: Modelling, Inversion and Data-processing in Near Surface Geophysics II
Publication date: 09 September 2018
Info: Extended abstract, PDF ( 536.19Kb )
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In this work a simplified approach to array optimization for the DC resistivity and induced polarization method have been created and tested. The optimization method uses the centre of the sensitivity function for the individual electrode configurations, called the mass centre, which is spread over the area of investigation, wherefrom the name Spread of Mass Centre (SMC). This array has been tested both in theory through forward modelling and in the field. The theoretical results have shown that the SMC array generally measure higher voltages than the common multiple gradient array, which could indicate an improvement in signal to noise ratio when using the SMC array. For the field test it was found that the SMC array achieved comparable resistivity results with slightly higher mean residual in the inversion than the multiple gradient array, while the integral chargeability results show a more significant difference with the SMC array having significantly higher mean residuals. In general, the SMC array show promising results for a simple optimized array which is computationally light and highly compatible with multichannel optimization.