SEGJ Technical Conference

Stability evaluation of geomagnetic transfer functions based on Non-negative Matrix Factorization

Abstract MT is one of the electromagnetic exploration methods, which can visualize deep subsurface resistivity structure. Recently, MT surveys are operated for the purpose of monitoring resistivity structure. In MT, magnetic field signals are assumed plane waves. If the assumption is collapsed, resistivity structure change fictitiously. Hence we must evaluate the condition of magnetic field signals.In this study, we use Non-negative Matrix Factorization (NMF), which can decompose spectrogram into several bases. By NMF, we extracted the spectrum pattern differences between local and remote site and evaluated the TFs stability.